RADIO WORLD

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RADIO WORLDA Weekly Paper Published by Hennessy Radio Publications Corporation from PublicationOffice, 145 West 45th Street, New York, N. Y. Telephones: BRYant 0558, 0559

Vol. VII. No. 5. Whole No. 187. October 24, 1925 15c per copy, $6.00 a year

The 3 -in -1 RF Receiver

0 11.Na3O B*No.2

0 B*No.1O B-OA.

FIG. 1, the wiring diagram

By Sidney E. FinkelsteinAssociate, Institute of Radio Engineers

PART 1.THE tuning of three circuits by one

motion is possible by several means,one of the most attractive being by use

of 3 - section con-denser, Cl in Fig. 1.It is used in a 5 -tubetuned radio -frequen-cy set in which apotentiometer is usedfor stabilizing pur-poses.

Granting that theproper inductancesare used in the sec-ondaries it is possibleto make a mightyfine receiver that willprove popular withall members of the

family. The tuning case is remarkable,as there is only one dial to handle. Thevolume is at least as much as anybodywould want, and in some cases a littlemore than that, due to the fact that somespeakers can not handle a terrific amountof volume. In any event it is possible todrop the volume by turning the first radio -frequency stage rheostat down a littlelower. This is RI in Fig. 1 and shouldbe 30 ohms for the 201A line of tubes.The usual value recommended for othercircuits using this tube is 20 ohms, andthat is correct there, but in this case thecontrol is rendered finer by the inclusionof a rheostat of higher resistance. The

SIDNEY E.FINKELSTEIN

of the set that tunes three secondaries with one condensersecond AFT may improve some sets.

only other rheostat used, R3, which gov-erns the detector tube, should be 20 ohms.The detector rheostat and potentiometer,once their settings are determined, maygenerally be left that way.

The potentiometer P, which should be400 ohms or more, plays an importantpart in the operation of the circuit, sinceit varies the bias, if any, on the two RFtubes. In effect it is a synchronizer, be-cause it brings the operating character-istics of one RF tube to about the sameplane as those of the other. A given biasfor one tube will cause it to work in themost efficient manner, while a differentbias will have to be used to produce thesame effect on the other tube whose gridreturn is connected also to the potentio-meter arm. Hence the better tube isbrought down to the level of the poorerone, in point of performance, and this hasbeen used as an argument against theemployment of a potentiometer as an RFstabilizer common to two or more cir-cuits. Two separate potentiometers couldbe used, of course. The argument issound, but it hardly stands up under thepractical considerations of the day, whichare decidedly in favor of simplicity, andso long as simplicity is consistent withgood reception over long distances, fineselectivity and plenty of volume, no moreis asked. Those who care to abide by theother school of reasoning may use a po-tentiometer for each of the two RF tubes,but for practical purposes this is decidedlyunnecessary, and the results obtainablefrom the receiver just as it is shown inFig. 1 will confirm this.

It will be noticed that a C battery is

motion. The reversed secondary of the

used. This might not be necessary in allcases, but it is well to have the connec-tions there, for they may be bridged bybusbar if the C battery, on experiment,proves not to improve the signal. It isused in the audio circuit only. About 3to 4% volts should be tried.

The actual construction of each tubehas much to do with the necessary bias,and discussions of biasing all too oftendisregard the tube construction, whichmay not be the same for any of the fivetubes you would buy for the set. Thedistance of the grid from the plate is im-portant, and this is something you cannot judge, for you can not see, much less,measure it. The C battery takes care ofthese' considerations, and often will morethan compensate for its use, cutting downthe B battery drain particularly.

The StabilizationAll forms of stabilization or neutraliza-

tion must necessarily introduce some formof loss. In the case of the neutralizingcondenser it may be only that slight lossoccasioned by the extra resistance incor-porated by the small balancing condenserin the counter -oscillatory circuit. This isno indictment against the Neutrodyne,which is an excellent circuit, but it merelyexpresses the condition existing by virtueof the tube action itself, where at thehigher frequencies in the broadcast belt(lower wavelengths) the capacity existingbetween the elements inside the tube it-self set up free oscillations that eitherroughen or distort reception or preventit entirely. Naturally some means mustbe provided for getting rerent;nn

4 RADIO WORLD October 24, 1925

Stabilizing of Sets Explained

HOW THE WIRING is done underneath the subpanel is shown in this bottom -viewphotograph. The audio -transformer bases are on the same horizontal plane as thebottom of the front panel, although the photographic perspective does not indicatethis. Note the slot through which a peep is obtainable at a part of the variablecondenser. The potentiometer is in lower center. Note the arm or mid -point of thepotentiometer is connected to one end of L4, on a straight line, and that a busbarlead is soldered at right angles and connected to the corresponding terminals ofL2 and L6. In the coil at left, looking at the core, lower right, one catches a glimpseof the mounting bracket. This photograph shows that an extra half turn is put onthe secondary so that the grid terminals of the coils will be very close to the socket

grids.

TOP VIEW, showing how the brass angles secure subpanel to the front paneBoth are hard rubber. Note that the variable condenser is mounted upside down.

THE ANGLE of mounting the coils is shown very clearly in the above photograph.

good reception, at that, and no matterwhat means that happens to be, so longas it succeeds, it is a good one. A givenmanner of stabilization may function alittle more efficiently than some other,but this is something for the hagglers toworry about, rather than a matter of greatconcern to the home -constructor, to whompractical demonstrations in terms of qual-ity of reception, volume, distance and sim-plicity mean more than geometric compu-tations based on meter readings.

The Coil Conneetioiss

The best way to connect the coils is thatshown in Fig. 1, where the terminal jointsare defined, but where the position of thecoils themselves is not shown, for that isat an angle in fact, say 57.3 degrees. Tomeasure this angle accurately a protractoris necessary, or some other mathematicalcalculation must be used, but assumingthat these means are not at every one'scommand, it is all -sufficient to mount thecoils as near as possible to the fashionshown in the photographs. The distancebetween coils is great enough (2" at near-est points) to allow some leeway, andbesides the potentiometer control is better equipped for getting rid of over-oscillations, even those induced by interstagecoupling, than the neutralizing condense.method, because of the greater scope ofvariation and the broader method of ap-proach.

The CoilsThe coils for the set depend of course

on the capacity of the condenser. As thewhole wavelength band may be tuned inwith the .00025 mfd. type variable con-denser, provided suitable inductance isused in the secondary, and as a'3 -sectioncondenser is embodied in the hookup, bothelectrical needs and space conservationare served when the coil is made for the.00025 mfd. type of 3 -section condenser.This instrument may be rated .00075,where the combined capacities are con-sidered, or .00025, where the manufacturerrefers to the maximum of a single section,but you will be getting the right instru-ment if you ask for a 3 -section .000025mfd., for even the manufacturer whoidentifies his product by the sum of thetotal capacities will know what you mean.

The tubings necessary are three of 3"outside diameter, 1g" high, and three of2y4" outside diameter, lg" high, Theprimaries will be wound on the smallerdiameter forms and the secondaries onthe others. The primary will then beinserted inside the secondary.

Using No. 26 single -silk covered wire,put on 60% turns for each of the sec-ondaries. Four tiny holes are drilledwhenever a winding is put on any of theforms. Two of these will be in paralleland in the direction of winding, andthrough them the wire end will bethreaded for anchorage. For instance, instarting to wind the coil, measure down3/4 or ;V from one circumference, makethe two holes. Leave a few inches ofwire as excess and start winding. It willbe found that the winding takes up ap-proximately 1". but if it is a little moreor less do not let that concern you. Holdthe end of the winding and drill thetwo remaining holes on the same linethat would be followed if the windingwere continued farther. Then cut thewire about 2" from the point where itwill be introduced in the pinholes andthread. It is safe to measure 1" (axiallength of winding) and arbitrarily put thetwo pair of holes on circumferential lines.but each pair at diametrically oppositepoints, because the winding will fit on

(Continued on Page 26)

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A Phonograph Cabinet Set

nd

FIG. 1, showing

Receiver is designed forutilization of the cabinet,without use of the phon-ograph itself and withan external speakerplaced in the record com-partment next to the oneused for the panel.

By Lewis WinnerAssociate, Institute of Radio Engineers

PART I.ss I HAVE a console phonograph. I

I would like to place a radio set inthere, but I don't know of any manu-

factured set that willfit in the compart-ment, which hassuch odd measure-ments."

My brother, Her-man, said this to meover the telephoneone night.

"Can't you buildthe set?" I asked.

"No, not very sat-isfactorily," he an-swered.

"Yes, you can," Iinsisted. "Go to it.There's lots of fun

in it. Also when you build your ownyou nearly always know just what thetrouble it, in case the set stops dead orjust gets blah."

Problems to SolveHe finally agreed to build the set him-

self. Soon after he said goodbye and Istarted to think what type of receiverwas best to place into a phonograph. Theset should give plenty of volume and atthe same time quality must be good. Hemight want to use the tone chamber,and to make one that gives any sort ofdecent volume requires a very large out-put. This is only obtainable with atleast three stages of audio -frequencyamplification. Of course, he might stillwant to use an external speaker, whichcould be placed into the other record par-tition. There are two record partitionsin every console type, one on each end.In the center is the tone chamber. Inany event, a loud set was desirable. Butthat does not mean that quality of re-production must be ignored.

No matter how many radio -frequencytubes you add in front of the detector,the volume does not increase in propor-tion to what it does when adding anAF stage. In the many sets that I havemade I found that when adding more thanone tube ahead of the detector, the vol-ume increase was so small that the 'extra

LEWIS WINNER

the electrical diagram of the set built in a phonographRF tubes cou d be taken out, the wiringbeing rearranged, and you wouldn't noticethe difference. This, of course, happenedmostly on locals. On distance stations theextra tube did help, but to only a smallextent. That is, if you are a carefultuner you could tune in those same sta-tions with the extra RF tube or tubesout. In other words, the first portionof the circuit need contain only one stageof radio -frequency amplification ahead ofa regenerative detector. Follow that bythree -stages of audio -frequency amplifi-cation and you would have enough.

Now what stumped me was : what typeof audio -frequency amplification was tobe used? The first stage should be ofthe regular transformer coupled type.The second and the third stages stuckme for a few moments, during which per-iod resistance coupled, choke coil andauto transformer coupling were thoughtupon, the auto -transformer method waschosen. Why? This will be explainedlater.

Trying Circuit on a BreadboardI went over to my test board and tried

out a circuit which I thought to be ex-cellent for this purpose. I had hardlyfinished wiring up the test circuit whenthe door -bell rang. There stood my oldfriend Jack. You remember Jack, the fel-low who was so overjoyed at hearing aset of mine that he junked his and builtone I described for him and which Ihad working in my home.

"Hello, Jack. Say, you sure are wel-come. How's the set working?"

"Nothing to beat it. Say, you know BillBeldham?"

"Sure do.""First I built the set as you described

it to me, and it worked fine. However,Mrs. Beldham and Bill paid us a visit.They wanted to know if I could place theset in the phonograph that we have. Isaid that was a great idea."

"Yes," I reminded, "especially as Billis an M. E."

"Well, you know, Winner, I am prettyhandy with tools myself, and so we start-ed. We took our time with it, and al-though it took us quite a long time, itwas well worth it. It works as well asit looks. There was nothing really diffi-cult to do, except rearrange the parts.The shelf was cut in two, two socketsplaced on top, and three on the bottom.Did a little more juggling with the rheo-stats and the condensers and the resultyou shall see when you come over to thehouse."

"Well, if that isn't luck, what is?""Why? What do you mean?""My brother called me up a few min-

utes ago and asked me to come over tohis house and take measurements of hisphonograph compartment, because hewanted to place the radio set in it. Ithought a little while about the circuit,but I soon puzzled that out. I had justbegun to wire up the set when you rang

cabinet.

^-- 8+1-- B -

the bell and if you will wait a while 1will hook it up on this bread board, andlet you hear it. However, the thing thatbegan to worry me while wiring up theset was where to place the parts, but itseems to me that you have solved that.The tubes also are five in number, thereare only 2 -controls (except for the poten-tiometer), and the panel, the layout isthe same. The circuit change will notalter the layout. Now, the only thingthat I have to worry about is that yourcompartment should be of the same sizeas my brother's."

I gave Jack the circuit diagram of thespecial receiver which I was hooking upand which is shown electrically in Fig.1.

After three-quarters of an hour ofof struggle with the wires I hooked upthe set. Of course, folks, you must real-ize that I had no panel or any thing todrill at all. Everything was laid out ona board.

There is an objectional feature abouta bread board layout in that the set al-ways works better here than when on apanel and in a cabinet. This is due to theuncrowded wires. It is therefore wise,when listening to the results, to take thisinto consideration and expect a little lesswhen the set is placed in a box. In otherwords, the bread board layout is not aperfectly fair test, but by the proper com-pensations the results can be made to bealmost equal in most cases. This is takencare of in this set.

"Boy, what volume," exclaimed Jack"Cut it down, will you?"

I realized it was a local, but I was sat-isfied with the volume that I was lookingafter was obtainable. The quality was abit harsh. I then took out a fixed re-sistance from the grid circuit of tube No.4, and put a variable resistance there.

"Note any difference, Jack?" I asked."No, not yet."I then started to vary this resistance."Leave it at that point," he advised.

"Boy, that's great. Say, I am going totry that stunt. I think it's better thanthe choke coil I have in my set now."

Getting the Panel DimensionsThe volume was not great due to the

fact that the potentiometer was out ofadjustment. Soon, the volume wasbrought up, and the set functioned per-fectly. The phonograph model had morevolume. The plate is coupled to the gridby a by-pass condenser in both the firsttube and the detector tube. That givesthe set added volume.

At Jack's invitation I went over to hishouse. I took out my ruler and startedto take measurements of his set. Thewidth of the panel was 12". The height(sometimes called depth) of the panelwas 18". The depth of the compartmentwas 14k".

"Well," I said. "now I have to findout the dimensions of my brother's com-partment. If they are both the same I

October 24, 1925 RADIO WORLD

How to Arrange the Panelam in luck. I'm going over to his housenext Sunday."

On the appointed Sunday I went tomy brother's house. I went over to thephonograph, and with a wish that themeasurements would be all right, tookout my ruler. The width was 12". Thatwas one relief. The height was 174..

"There must be some mistake," I said,"because Jack's measured 18" and thisone is Me.

Jack's Home is VisitedI then took another chance at the

length, and found that I had made aslight error, in that I placed the ruler onthe inner block, instead of the outer block,which was Yi" in width. This made thelength 18" and brought forth a deepsigh of relief. The depth proved to bethe same also, or 1444.

"Herman," I asked my brother, "wouldyou like to go over to Jack's house andsee the radio that he has in his phon-ograph? This will give you an idea ofhow yours will look. Then you can comeover to my house and listen to the setthat I am going to put into the phon-ograph, this being different from the onehe has in his."

He readily assented. After a glance at,Jack's outfit, Herman exclaimed:

"Looks great. Will mine look likethat?"

"Yes.""Say, Jack, will you please turn on the

set and let my brother listen to it?" Iasked.

Jack soon pulled the switch, and themusic came rolling forth.

We all moved our chairs around theset. Bill disconnected all the wires. Billthough, knew all about the mechanicalfeatures and therefore was chosen to dothe explaining to my brother. He thentook the set out from the compartment,so that we could see all the details of theset proper.

"I think it would be a good idea," saidmy brother, "if you drew a small sketchof how the exterior looks, so that wecould feel more at home when you aretelling about the dimensions, as they lookquite confusing to me."

Bill Describes LayoutThe picture shown in Fig. 2, is the

panel view. Bill explained:"The panel, of course, is 12" wide by

18" deep. The variable condensers, C2and C3, are placed in the center, that is,9" from the top and the bottom of thepanel, and each 3" from the left-hand edge,hence at this point drill a hole 5/16" indiameter. Now drill the condensermounting holes from templates. The cen-ter hole in each case is for the condensershaft. Condenser C3 is mounted 6" fromC2, on the center line. The two rheo-stats, which control the filament tem-perature of the radio -frequency and thedetector tubes, are placed at the top, asyou see. R1, the RF rheostat, has a holedrilled for its arm 3" from the top and 3"from the left-hand side of the panel.Don't forget the rheostat mounting holes.The diameter, of the shaft hole is 5/16"and the dimensions for the holding holesare rA". R2 is placed in the same line.The center hole for the arm is 3" fromthe top and 3" from the righthand sideof the panel. The holding holes areusually 1/2" from the left and the rightof the center hole. The diameter of thecenter hole is 5/16" and the diameter ofthe holding hole is ,A". Now for thepotentiometer, R4. The center hole forthis instrument is 6" from both the leftand the right-hand side of the panel, and3" from the bottom. A 5/16" hole is

!/2

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---

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6"

3"

FIG. 2, showing the panel view of the receiver.utilized for the center hole, and twoIcy" holes are drilled on both right andleft-hand sides of the hole, the distancefrom this point being 1/2". We will nowturn to the jacks, of which there are two,J1 and J2. The first jack, J1, is placedat the left-hand edge of the panel. A'V hole is drilled 2" from the edge and2" from the bottom. The other jack isplaced at the right-hand edge. This is2" from the edge and 2" from the bot-tom. The diameter of the hole is also%". The switch now remains. This isplaced on the same side as the secondjack, J2. The hole is also 7A3" in diameter.It is 4" from the right edge, and 11/2"from the bottom. The only holes thatremained to be drilled, are the angle ironholes. Here is where you have to followme carefully, as I had a lot of trouble ingetting these dimensions right, and theleast little slip will embarrass you. Ofcourse, these dimensions depend upon thetype of angle irons you use. I used theplain brass type. These have two holesin them, and they are 2%" long. Thatmeans that if they were straightened outthey would measure 5". The width ofthese irons is 1". The diameter of theholes is %.".

Jack then handed my brother an iron.

"Looking at it so that a straight por-tion with the holes faces you, and theother portion is on a horizontal line withyour eye, the top hole is 1/2" from thetop and the other hole is 1/2". from thebottom. The same applies to the holewhich is on the horizontal axis portion ofthe iron. The holes on the panel are1/2" from the edge. There are two oneach edge, and Iwo on each side, mak-ing a total of four on one side and fouron the other. The top hole is 6" fromthe top of the panel, on both sides ofthe panel. The other hole, is 1 4" fromthe one just drilled. This means that therewill be two holes on the upper portionof the panel which are in line, and 1W'from these holes there will be two moreholes which are in line. All in all, therewill have been 4 holes drilled. Now atthe bottom, the iron is in the same posi-tion, and the bottom hole is 3,4" from thebottom. Do not confuse this with thetop hole, as this has not yet been touched.We are now working upward and notdownward as we did with the above iron.The top hole is 1h" from the bottom hole.They are both 1/2" from the edge.

"This applies to both edges. That is,there will be a pair of holes, 3;4" fromthe bottom on both sides which are in


Assembling Phonograph Set

FIG. 3, showing how the back of the set appears. Note the side view on theof the large drawing.

line. There will also be another pair ofholes lh" from the ones just mentioned,which will also be in line.

"That is all there is to the panel drill-ing and we will now tackle the interiorof the set, which is a bit more difficult.Of course several parts already aremounted, that is, the variable condensers,the rheostats, the potentiometer, the

right

jacks, the switch and the angle irons havefound their places. Here are the draw-ings for the interior of the set. Fig. 3is the diagram Bill referred to. The shelfthat the sockets, 1 and 2, the coils, LI,L2, L3, L4, the grid leak and condenser,and the fixed condensers, Cl and C7, areplaced on, is 11" long and 2,A" wide.Socket 2 is placed 2.1/4" from the right-

hand edge. This will take up 13/,". Theouter circumferences are ;6" from theelongated edges. This will exactly centerthe socket. Socket 1 is place 2g- fromthe left-hand edge. The outer circum-ferences are 14" from the elongatededges. Socket No. 3 is placed 214" fromthe left hand edge on a shelf 11" longand 3" wide. This as you notice is Yrwider than the one above. Socket No.5 is placed 2/t" from the left-hand edge.Socket No. 4 is placed 514" from the rightand the left had edges. Place all thesesockets near the outside edge; that is theedge way from the panel. In between.sockets 3 and 4, or 334" from the lefthand edge, place the audio -frequencytransformer, which is called AFT1 in thediagrams. This is placed underneath theshelf. That means that four holes willhave to be drilled to hold the transformer.These holes will best be determined byplacing the transformer in its place andmaking small dots through the holes inthe feet of the transformer with a pin.Then where these pin marks are, drillholes. The next audio -frequency trans-former, which is called AF2, is placed inbetween sockets 4 and 5, underneath theshelf in the same manner as AFT1. Thelast audio -frequency transformer is placedin between the righthand edge and socket5. In all these cases I have not given thespecial dimensions for centring, as thyspecial dimensions for centering, as theywill vary with the different transformersthat you will get.

"Now, the resistances, R3, R5 and R7are all placed near to the filament bind-ing posts of the sockets. This is clearlyshown in the diagram. The large con-denser C5 is placed on the left hand sideof socket 4. The condenser C6 and theresistance R6 are placed on the left ofsocket 5. The leak and the condenser canbe placed as I have it in a special holder.Don't forget that we are looking at theset from the back, and therefore what isreally left-hand on the front is right-handfrom the back."

[Past II, the conclusion, will be publishednext week.]

Plate Voltages for the RX-1 DiscussedBy H. C. Hight

In last week's issue we described theconstruction of the RX1, concerningwhich a few further remarks are perti-nent.

First of all, the antenna coil is of theconductively coupled type instead of in-ductively coupled, which means that inorder to obtain the selectivity necessarywhen used in districts near broadcastingstations, a short antenna should be used.Remarkable results may be obtained witha wire 30 feet long, this will give plentyof volume and real selectivity, and ofcourse the wonderful tone quality forwhich this circuit is fast becoming famous.

Where selectivity can be sacrificed fordistance antenna length may vary from50 to 100 feet. While on the subject ofDX it must be said that the RX1 is nota set for a rabid distance hound. It willbring in programs from a distance ofseveral hnudred miles, but as there isabsolutely no regeneration, it can not heexpected to do the impossible. The RX1is the ideal set for those who desire aboveall else perfect tone quality, simplicity ofcontiol and freedom from squeals andhowls. This class of radio listeners willfind great delight in the entertainment

that can be received so easily and so freefrom undesirable noises.

Another interesting feature is the lackof any set noises, that is, sounds whichoriginate within the set itself. RF anddetector tubes function best when oper-ated with filament rheostats turned verylow. This fact coupled with the absenceof regeneration make this receiver oneof the quietest in operation that has sofar been devised.

A word on plate voltages. We said lastweek that 67V on radio frequency tubegave best results when using the tubessuggested, and further tests have provedthis to be correct. But in some cases theuser may find more than 22 volts to beadvisable on detector plate when usingthe Magnavox tube. 45 volts will pro-duce great volume, and will not be a bitcritical but 22 volts will probably satisfythe average person. In the event of beingable to secure a Sodion detector, 22 voltsis the correct amount to use on its plate.

The use of 30 ohm rheostats for RF anddetector cannot be too strongly advised,as they give better control of filamentconsumption than a 20 ohm rheostat. Ifthe transformer and resistance unit asspecified are used, no trouble will be hadwith the audio end. A "C" battery may or

may not be used. It makes practically nodifference in tone quality of RX1, but ofcourse will, if used, somewhat reduce Bbattery drain.

It is advisable to use only the veryhighest quality of variable condensers inthis set. If using condensers of the con-ventional rotary type, one of .0005 mfd.capacity should be used as antenna tuner,and a .00035 mfd. in the detector stage.Excellent results are obtained by the useof the Wade, which is of unique con-struction, and accomplishes a very wideseparation of low -wave stations. The useof a 360 -degree dial and the peculiar con-struction and operation of plates makethis wide spacing possible. As this con-denser has a very low minimum capacityit covers a very wide range. And the.0005 mfd. can be used in both stages.Dials can be set together on some givenstation and they will log very closely instep over the entire broadcast band.

Anyone who properly constructs thisset, uses it on a short aerial and agood ground, and with a good speaker,preferably a cone, can be absolutely as-sured of having a set that will receivethe greatest admiration from any one whocan appreciate quality and clarity, com-bined with simplicity and quiet operation.

October 24, 1925 RADIO WORLD 9

Completing the Thoroughbred

[Part I of this article on the constructionof The Thoroughbred, a 1 -tube set thatbrings in distant stations (DX), wasdescribed in last week's RADIO WORLD, issueof October 17. The conclusion is publishedherewith.]

By Herbert E. HaydenIllustrations by the Author

PART II.THE home-made box that constitutes

the cabinet for the Thoroughbredwas made larger than was absolutely nec-

essary for the partsemployed, the reasonbeing the advisabilityof having ampleroom in case someother parts were sub-stituted. For in-stance, regarding thevariable condenser,which is .0005 mfd.maximum capacity,i. e., 500 micro -micro -farads, almost anyvariable condenser ofthat capacity will fill

HERBERT E. the bill. As for theHAYDEN tuning coil, you maywind one yourself, if you like, but theregeneration control, which is a Claro-stat, has to be purchased, and I supposethat most persons will prefer to buy thecommercial tuning element with the Claro-stat or variable resister included, andwhich unit is known as the Clarotuner.

The CollThe primary should have the regulation

amount of inductance, which, on a spider -web form, say, would consist of 12 turns ofNo. 22 single silk covered wire, if woundat the hub, or about half that many turnsif wound on the exterior of the form,which, by the way, should have an out-side diameter of 5 or 5%". The second-ary would consist of 50 feet of the samekind of wire, while the fixed tickler coilwould consist of twice as many turns asthe primary.

A good plan for those who would liketo construct their own coils would be towind the primary first, at the hub, puttingon the 12 turns, then wind the secondary,which would consist of about 48 turns, orwhatever the 50 feet of wire amountsto, which would be approximately that,and then the fixer tickler. That enablesthe energy to come in through the primaryto the secondary, while the feedback isaccomplished by means of the fixed tick-ler without necessitating the feedbackenergy to traverse the primary. This isa minor consideration indeed, and oneneed feel no compunction whatever aboutwinding the coil the other way, or usinga unit that may be wound the otherway.

The Interior AssemblyThe completed set was shown in the

THIS photograph clearly shows the interior view.

front cover of last week's issue, and itgives a very good idea of the externalassembly. However, for the "interiordecorations," as I might properly callthem, Fig. 12, shown to the right of thisprinted matter, clarifies any doubts thatmay have arisen. The binding posts areshown on the right-hand side of the photo-graph, and that represents the back ofthe set. Note how the binding postscrews protrude into the interior. Rightbeside them is placed the fixed grid con-denser, .00025 mfd., which has clips formounting the fixed leak. The value ofthis leak is not so very critical that from2 to 5 megohms may not be used, but Iused 2 megohms with fine success.

The front of the set is represented bythe variable condenser, at right in Fig.11, while the sides of the cabinet are iden-tified by the rheostat, on the one hand,and the Clarotuner knob on the other.The two binding posts beside this knobare for telephone connections. The an-tenna and ground posts are lined up withthe battery binding posts in the rear.

The variable condenser I used (Con-necticut) is of the single panel mounttype, and the manner of mounting thisis shown in Fig. 11.

TuningThe tuning of the set is simple indeed.

The variable condenser, of course, deter-mines the wavelength. This is becausethe aperiodic primary brings in virtuallyall frequencies even up to the ultra -fre-quencies (very short waves), and alsothe waves higher than those of the broad-cast band. Therefore it depends on thecondenser, in conjunction with the fixedsecondary, to reach the proper limits. Thisit will do, if of .0005 mfd. maximum capa-city.

The set should tune from about 185 to

555 meters. Any station within normalreceiving range should be brought in with-out difficulty. Bringing in DX is, as ever,.a little more difficult. The knob of theClarotuner is turned until a sort of sear-ing sound is heard for the particular con-denser setting of the moment. This de-notes the approach to the regenerationpoint. Here is where the set is differentfrom other regenerators. The approachto saturation is so gradual that the likeli-hood of "spilling over" is greatly dimin-ished, and likewise the facility for tun-ing out any whistle is enhanced, so thatthe program may be brought in clearlyand beautifully. The variation of theresistance in the plate circuit has a min-imum, almost zero effect on the wave-length tuning, and this is another attrac-tion.

Trouble HintsIf the set shows a tendency to "spill

over" easily, the cause most likely is toohigh B battery voltage, too low a gridresistor (i. e., leak should be of a higherresistance, so the leakage path will beslower), or a tube that is a very pooroscillator. Also try reversing the leadsto the fixed tickler or coil.

Should no signal result at all, look tothe battery connections, see that aerialand grounds are connected, and general-ly look through the set for broken orloose connections. The fault will be inthe wiring, of a certainty, provided all ex-ternal connections have been made.

If the signals are not loud enough, testyour B battery voltage with a voltmeterplaced in parallel with the B battery,while the set is in operation. Grantingyou are using the 45 -volt post, this shouldshow a reading of no lower than 38 voltsfor effective use, and if it is lower, thenget a fresh B battery.


How to Use Fixed CondensersTo Avoid Distortion and Increase Efficiency

SERIES COUPLING by means of a fixed condenser, C2. Lt should be very small,say .0001 mfd., for loose coupling and large (e.g., .002 mfd.) for tight coupling.Fixed condensers used, as C2, in RF work, should have only the best dielectric. C3is the grid condenser, used for blocking the grid current in the detector. The dotted

condenser is a bypass. (Fig. 1.)

[In the following important article J. E.Anderson, noted radio engineer, discussesfixed condensers from both practical andtheoretical viewpoints and corrects errorscommonly made.]

By J. E. AndersonConsulting Engineer

IN every radio receiver, from the simplestcrystal set to the most elaborate Super -

Heterodyne, fixed capacity condensers areemployed. They areused for a variety ofpurposes, and theyare sometimes mis-used. Some of theirlegitimate uses are asby - pass condensersfor high -frequencycurrents across low -frequency or directcurrent apparatus, asblocking condensersto prevent audio -fre-quency currents fromentering radio fre-quency apparatus, or

to separate alternating current from direct.Their misuse is limited usually to the

J. E. ANDERSON

A FIXED condenser, C, used some-what similarly to a grid blocking con-denser. The above is a direct coupledcircuit, tubes 1 and 2 being coupledby condenser, with the aid of resistors,for audio amplification. For suchaudio coupling C should be as large aspossible. The large condensers areexpensive, so .25 mfcL is a frequentcompromise, yet 4.0 mfd. would bemuch better. The reasons are given

in the text. (Fig. 2)

capacity of the condensers used for agiven purpose.

Use in the Antenna CircuitOne of the first uses for a fixed con-

denser is in the antenna circuit to shortenthe antenna's natural wavelength. It isconnected in series with the antenna andits purpose is to reduce the effective capac-ity in that circuit so that the circuit maybe tuned to shorter waves. It is usedeither when the inductance in the antennacircuit or the self -capacity of the antennais too great. Since this condenser is in atuned circuit, or an approximately tunedcircuit, it should be a low -loss condenser,with either air or mica as the dielectric.The required size depends on the loadinginductance coil, on the capacity of theantenna and on the wavelength of thesignal.

The Coupling CondenserAnother use for a fixed condenser is

for coupling, to transfer energy from onecircuit to another. Two types of couplingmay be distinguished, the series and themutual. The series type is illustrated inFig. 1, C2. Mutual coupling exists wherea condenser is common to two differentcircuits and where the voltage across thecondenser as set up by a current in thefirst circuit is the voltage transmitted tothe second circuit. For series couplingthe condenser must be very small forloose coupling and large for close coupling.

For the mutual condenser the capacitymust be large for loose coupling andsmall for close.

Whether a given condenser is to beconsidered large or small in a certaincircuit depends on its impedance to thecurrent flowing in it, and the impedancedepends on the frequency as well as on thecapacity. For equal impedances in com-mon to two circuits the coupling will bethe same. The impedance of a condenseris equal to .159 divided by the product ofthe capacity and the frequency, the ohm,the farad, and the cycle per second beingthe units. At 50 cycles per second theimpedance of a 1.0 rnfd. condenser is 3,180ohms. At 5,000,000 cycles per second theimpedance of the same size condenser isonly .0318 ohm.

When coupling condensers are used inradio -frequency circuits only instrumentshaving the best dielectric should be used.

The Grid CondenserPerhaps the best-known use for a fixed

condenser is for blocking the grid currentin a detector. This is illustrated by C3 inFig. 1. Almost invariably the value usedfor this condenser is .00025 microfarad.The use of this particular value is largelya matter of. habit. The optimum valueto use depends on many factors, namely,the type of tube used for detector andon the manner in which it is operated,on the value of the grid leak connectedacross the condenser, on the natural leak-age from grid to filament through the in-sulation of the grid or the condenser it-self, and on the intensity of the signalvoltage. If the insulation of grid is pooror if a large value grid leak (low resist-ance but large leakage) is used a smallcondenser works best. Similarly if thesignal is weak a small condenser worksbest, one very much smaller than the.00025 mfd. ordinarily used. Conversely,if the insulation of the grid is very good,or if a small leakage (high resistance) isused, the condenser may be larger; andif the signal is very strong it is betterto use a larger condenser. The best valueto use also depends on the ratio of thecarrier frequency to the average carriedfrequently. Ordinarily the value of thegrid condenser may be reduced to .000125or even .00005 mfd. with good results.And the smaller it is, other things re-maining constant, the more sensitive willthe detector be. The limit of reduction,for a given signal intensity and givengrid leakage, will be when the grid blocks.

A Direct Coupled AmplifierA use for a fixed condenser similar to

that of the grid condenser is the blocking

C3, BETWEEN the end of L3 and the A minus lead, to lower right of the secondtube, is used as a bypass. C5 is also a bypass condenser in its conventional positionon a reflex set, across the secondary of the first AFT (lower left). Bypass con-

densers should be no larger than necessary. (Fig. 3.)


What Capacity Values Are BestExplained by One of America's Great Authoritiesi-C.Tre 0-

Rnt L,

L I

0-"--11111H11111 - -r -c'

71A

A FIXED bypass condenser across the B battery is shown above (C), to right of C4, a bypass condenser for RF currents (to rightof second tube from left) should not exceed .002 mfd. The intermediate frequency condensers in the above Super -Heterodyneare C3, to right of second tube, across primary, and the ones across succeeding secondaries. (Fig. 4.)

condenser used in a direct coupled ampli-fier, illustrated by C in Fig. 2. This isused to keep the high positive voltageapplied to the plate from reaching thegrid of the succeeding grid. This use isa necessary evil. Essentially this con-denser is a series coupling condenser.and what was previously said concerningthis applies here also. If the directcoupled amplifier operates at radio fre-quency, either high or intermediate, thevalue of the condenser may be com-paratively small, from .001 to .01 mfd.,depending on the frequency of the currentto be amplified. If the amplifierat audio frequency and the circuit is in-tended to amplify all audible frequenciesto the same degree, the value of the con-denser should be as large as possible.Only space and reasonable cost shouldbe the limitations. If the condenser issmall, low frequencies will be suppressedowing to the high impedance of the con-denser at these frequencies, and distor-tion will result. Condensers smaller thanone microfarad should not be consideredif the object is to construct a qualityamplifier.

The dielectric in one of these need notnecessarily be mica or air if the blockingcondenser is used in an audio amplifier.Paraffined paper will do. But it is essen-tial that the condenser be able to with-stand the highest plate voltage whichmay be applied to the amplifier.

Sometimes a large condenser is con-

\/OaO

CS,

0.L2

,C)O A

netted in series with the loud speaker tokeep the direct current from the tube outof the speaker windings. In this case itis even more important that the condenserbe large than when it is used between theplate and grid, and also that it be ableto withstand high voltages. This use of acondenser is illustrated in the 1926 ModelDiamond of the Air (Sept. 12, 19 and 26issues).

As a By -PassThe fixed by-pass condenser is used

in every radio receiver, and in manyplaces in every receiver that is in theleast complex. It is used across the head-set in a crystal receiver, across the head-set or the first audio -frequency trans-former in a tube detector circuit, acrossthe first intermediate frequency trans-former in a Super -Heterodyne, across thefirst coupling impedance in a directcoupled amplifier if the detector is directcoupled to the next tube, and they aresometimes used across the A, B and Cbatteries. They are always used to pro-vide a low impedance path for high -fre-quency currents across some device whichIs designed for low -frequency. currents.

The dotted line condenser in Fig. 1 isused to by-pass the radio frequency cur-rent across both the headset and the platebattery. C3 in Fig. 3 and C4 in Fig. 4are used similarly.

In reflex sets like that shown in Fig. 3by-pass condensers are used profusely

across the windings of the various transformers and the speaker. Condenser C5illustrates th..t use of a by-pass condenseracross the windings of the various trans-former. The use of a condenser acrossthe B battery is illustrated in Fig. 4,condenser Cl.

Plate Circuit CondenserA by-pass condenser should not be any

larger than is absolutely necessary toperform satisfactorily the work it is in-tended to do. If a condenser is used inthe plate circuit of a detector to by-pass

radio -frequency current across theprimary of the first transformer, to facil-itate regeneration, it should not be largerthan .001 mfd. for radio frequency. Ifthe circuit will not oscillate with this con-denser across the primary the trouble lieswith the tube or with the tuner. If thetube will oscillate over the entire scale oftuning condenser without any by-passcondenser in the plate circuit, then it isbest not to use any. In a non -regenerativecircuit it is doubtful whether the con-denser need be used at all. Certainly itneed not be larger than .001 microfaradfor radio frequency and .002 mfd. forintermediate frequency. Thus C4 in Fig.4 should not exceed .002 microfarad invalue.

Much larger values than those specifiedabove are often recommended for thevarious by-pass condensers in a circuit.

(Continued on page 24)

A

'IF

-toB+DET.1

o B+AMIi!

o B-A 4

0 A -

THE NEUTRODYNE, in which the neutralizing condensers are designated N. The dielectric should be air, not glass. (Fig. 5.)


DX on Less Than 10 MetersNot Practical, Says Taylor

By Thomas StevensonWASHINGTON.

Recent developments in high -frequencyexperiments at the U. S. Naval ResearchLaboratory at Bellevue have indicated tworather startling conclusions regarding thisphenomena.

One of these theories attempts to ex-plain why stations located within a fewhundred miles of a high -frequency trans-mitter cannot pick up its signals whilereceivers thousands of miles away, evenas far as half way around the world, canreceive them clearly.

The other is that it may never bepossible to utilize the frequency band be-low 10 meters for distance transmission.

Dr. A. H. Taylor, physicist in charge ofthe Bellevue Laboratory, is the author ofthese conclusions. Dr. Taylor bases themon the results of experiments over a longperiod as well as on the reports of ob-servers scattered throughout the world.Dr. Taylor would not discuss the possibil-ity of the utilization of high frequenciesfor broadcast transmission and receptionin the near future.

Effect of Earth's FieldsAccording to Dr. Taylor it is pretty

well established that the magnetic fieldof the earth influences the motion ofelectrons in the atmosphere and that ithas an important bearing on high -frequency waves, whereas the low -fre-quency waves are not appreciably affected.

"An appeal to this influence and to thewell-known laws of the reflection and re-fraction of waves," says Dr. Taylor, "hasresulted in a theory that appears to fitthe facts fairly well and which althoughby no means complete will at least, wehope, encourage theoretical and experi-mental work which will throw light onthe subject.

"Perhaps the most striking fact whichhas come out of the studies of high -fre-quency transmission is the obvious exist-ense of a skipped distance combined withthe tact that in many cases the signalsat relatively great distances are muchstronger than they are at relatively shortdistances.

"It appears that the change from normalradio conditions which has led to ex-traordinary range of communication withlow power occurs at about 130 meters or2,300 kilocycles."

Cites IonizationAccording to Dr. Taylor's theory, there

is a gradually increasing state of ioniza-tion in the high level of the earth'satmosphere. It is believed this is due tothe sun's rays and other causes. Thevelocity of radio waves is higher whentraveling through ionized regions thanwhen through non -ionized space.

When the wave is sent out by theantenna it travels at an angle toward theHeaviside -Kennelly layer. As ionizationincreases in the high levels, the velocityof the wave increases so that it is gradu-ally bent over because the top of the wavetravels more rapidly than the bottom.Thus, it is bent back toward the earth.From the reaction of the induced cur-rents in the earth's surface at the baseof the wave, the earth itself has an actiontending to straighten the wave out.

This means that the wave cannot be re-ceived at any point between the placesent out and the place where it again re-turns to the earth. Of course, there isalso a ground wave which makes thesignal audible for a short distance fromthe transmitting station, but fading onthe ground wave is very pronounced.

If the wave happens to come down

around 600 miles away, a smion in thatlocality can get a very good signal, whilea station 200 miles closer to the transmit-ting station could not pick it up at all.

Skipped Distances Compared"The skipped distance in the summer

night time is much greater than it is inthe daytime," says Dr. Taylor, "and theskipped distance gradually increases to-ward midnight. This is what we expect.Although the winter night skipped dis-tance is not accurately known, it is verydefinitely known that the skipped distanceis decidedly greater than it is during summer nights."

The length of the skipped distance, Dr.Taylor says, depends entirely on how closethe Heaviside Layer is to the earth. Thecloser the layer, the less the skip, andvice versa. Quite often there is a first,second, third and fourth skipped distanceas the wave travels up and down at anangle from the earth to the Layer.

Antenna Angle ImportantDr. Taylor says the angle at which the

wave leaves the antenna depends upon thefrequency at which transmission occurs.The higher the frequency, the flatter theangle; that is, the nearer the earth's sur-face the wave will go out.

"This means, for instance," says Dr.Taylor, "that at about 20,700 kilocyclesthe wave in order to be properly reflectedwill have to leave so nearly horizontal thatit will be very heavily absorbed by theearth. In addition, the curvature of theearth will actually get into the way of itso that it cannot reach the layer withsuch an angle as to be reflected. Accord-ing to this, we are not likely to see verysatisfactory communication over greatdistances on waves shorter than 10 meters,that is of higher frequencies than 30,000kilocycles.

"The only way we can conceive of com-munication at high -frequencies being feas-ible over long ranges would be to havethem started preferably in a beam fromcomparatively high altitude, so that theywould come to the reflecting area at a lowangle without being absorbed by theearth. This point, no doubt, will be provedor disproved in the not very far distantfuture."(Copyright, 1925, by Stevenson Radio Syndicate)

German Eiffel

A GLIMPSE of the winding stair-way of the radio tower of "Kooigs-wusterhausener." This new tower is656 feet high, the highest in Germany,and in the world it is second only tothe Eiffel Tower in Paris. An in-novation will be an elevator withinits girders, plans for which have been

completed. (Kadel & Herbert.)

RADIO INSTRUCTION COURSEWILL BE BROADCAST

New York University has announcedthe addition of a special course to preparemen through training in actual practice aswell as in theory, for positions as radiopublicity directors, radio program man-agers, professional radio lecturers andradio announcers. The students, says DeanJ. E. Lough of the Extra Mural Division,will be addressed by special lecturersprominent in the field of metropolitanradio.

The class will visit studios and operatingrooms of the leading broadcasting stations.Special arrangements for getting thestudents behind the scenes at these sta-tions have already been arranged for.

Wind Plays Radio Havoc;Moral: Use Strong Aerial MastsMany fans who were listening one re-

centt Saturday night realized how im-portant it is to put up a pair of strongpoles as antenna masts. Many folk camehome from work tuned in the radio andto their surprise heard nothing. Every-thing was checked up, the batteries,phones, tubes, etc. The erial was thenlooked at. Either the poles were down,the wire was sagging against the side ofthe roof or something to that effect wasin evidence. The reason was the terrifiswind.

In many homes signals were heard, but

they sounded as if they were fading. Thiswas due to the aerial sagging and, there-fore, swinging. In some cases the barecopper wire, which was attached to thelead-in was touching the side of the roof.This caused scratchy noises to be heardduring the whole evening, Therefore,place your antenna on strong poles, pullthe wire tight, leaving very little wireout, place the wire one or two feet awayfrom the wall and have it well insulatedat points nearest the roof.

Many persons thought their sets wereout of order, though it was only the aerial.

Attention Radio World Subscribers!Subscribers will note that the end of their subscriptions is indicated on the labelson wrappers. If your wrapper shows the date later than the current issue, you arebehind in your subscription. Please send payment for renewal. Thank youRADIO WORLD, 145 West 45th Street, New York City.

October 24, 1925 R A D 10 \V 0 R L I) 13

it

Invite -Yourself Planthe ConferenceAdopted for

WASHINGTON.The Fourth National Radio Conference,

to be held November 9, will take up forgeneral discussion and consideration mat-ters affecting radio communication in theUnited States from the viewpoint of thepublic interest. The conference will in-clude representatives of all radio activities.

The Eligible ListRepresentation will be accorded to mem-

bers of the following groups, one to eachconcern falling within any of them:

Broadcast stations, radio magazines,newspapers having a radio department,manufacturers of complete radio receivingsets, organizations of broadcast listeners,amateur organizations, commercial landradio stations, radio trade associations,press associations, United States Govern-ment Departments.

Representation will also be accorded thefollowing: Institute of Radio Engineers,American Institute of Electrical Engi-neers, American Steamship Owners Asso-ciation, United States Shipping Board,Farm Organizations, National ElectricLight Association.

Must File NoticeSo that proper arrangements may be

made for the accommodation of the con-ference it is essential that concerns orpersons desiring to participate adviseSecretary Hoover on or before October26, giving the names of their represent-atives. No person will be recognized asa delegate whose name has not been filed

with the Secretary of Commerce by thatdate.

While consideration will be given toradio activities generally, the principalproblems will be those affecting broad-casting. The subjects, so far as they canbe outlined at present, will be:

Recognition of the principle that serviceto the listening public must be the basisfor every broadcasting privilege and forall radio regulations.

The present saturation in broadcastingdue to the exhaustion of channels, andthe necessity for limiting the number ofstations on the basis of public service.

The requiring of permits in advance ofconstruction of broadcasting stations.

The necessity for operators' licenses,particularly for broadcasting stations.

Frequency band assignments for thevarious classes of radio communication.

The use of high power for broadcasting.The location of broadcasting stations

so as to prevent interference in congestedcenters.

Time division, duplication of frequencyassignments, and a geographical basis forallocations.

The use of broadcasting for advertising.Matters affecting amateurs.Matters affecting the marine and mobile

services.Rebroadcasting.

Open to PublicMeetings of the conference will be open

to the public and opportunity will be af-forded for the expression of views uponany of the subjects above outlined.

Classify Stations by Power,Regardless of Wave, Is Plan

WASHINGTON.Elimination of the present classification

of stations is expected to be recommendedby the Fourth National Radio Conferencecalled by Secretary Hoover to meet inWashington beginning November 9. It isbelieved that stations will no longer beclassed by letters as at present (such asClasses A, B, C, and D) but that for pur-poses of regulation the classification ofstations will depend upon their power.This will not affect call letters, e.g.,WEAF, WGBS, etc.

Allotment to EndIf this idea is adopted, the allotment of

wave bands for the different classes ofstations will be discontinued. The entirebroadcast band will be open to any typeof station whenever there is a vacancy.

The purpose of the proposed change isthat it will enable more stations to becrowded in and, it is believed, will tendto increase the service generally for thepublic. For instance, if a station of 500watts operates on say 350 meters in Bos-ton, it will be possible to also place a 100watt station on the same wavelength outin the middle west without interferenceresulting.

Greater ScatteringUnder this scheme, the powerful broad-

casting stations can be scattered through-out the entire broadcast band with thesmaller stations sandwiched in. Suchan arrangement would make availablemore channels for powerful stations with-out increasing facilities for smallerstations.

Secretary Hoover does not believe the

Conference will last more than three days.To extend the Conference beyond thatperiod, he believes, would work a hard-ship on delegates.

Secretary Hoover personally signedscores of invitations to the Conference.

A Sending Loop

Erecting huge inductance frameswhich weigh many hundredweights.This photo was taken at the govern-ment wireless station at Rugby, Eng-land, where new wonders are coming

to light. (International News).

Nearly 100 StationsLinked for Series ResultsNearly a hundred stations covering in

their range every corner of the UnitedStates, some of Mexico and a portion ofCanada, were connected in various chainsto broadcast the returns from the worldseries baseball games. WEAF playedgodfather to its usual array of stations,WJZ was hooked up with a similar chain,but the greatest combination of all wasformed by the Associated Press. Seventy-one broadcasting stations arranged tohandle reports of the first game receivedthrough the various offices of the pressassociation.

Wendell Hall SailsMr. and Mrs. Wendell Hall, radio sing-

ers, who were recently married by radio,sailed from New York for Europe on theBerengaria.

They will broadcast in England, Franceand Italy.

Speaker's Sales MethodsOffend Business Bureau

The special attention of managers ofbroadcasting stations was directed by theNational Better Business Bureau to theactivities of Henry F. Vortkamp, adver-tised as a radio authority, expert on cir-cuits, assembling operations, and nation-wide broadcaster, whose voice is familiarto millions.

Vortkamp, a convincing talker, is nowgiving attention to the radio industry.Recently, he was introduced to threeyoung men who later formed a radio com-pany and elected Vortkamp president.Several thousand dollars was spent.

Welcomed by ManyVortkamp has been accorded speaking

privileges over some forty or more broad-casting stations throughout the country.In a number of instances he representedto station managers that he is a radio ex-pert on a vacation, and that he will verygladly broadcast a ten-minute lecture.He has shown the manager a typewrittencopy of the text to be used. If accordedspeaking privileges, he has oft -timesstated, at the conclusion of his lecture,

that he will be very glad to send free toany "listeners -in" a special hook-up for aone -tube set he has designed.

This has usually resulted in a quantityof mail. The hook-up he faithfully sent.A part of the sheet, says the Bureau, isoccupied by advertisements which Vort-kamp has sold to radio manufacturers.

A Friendly LetterOn the reverse side of the sheet was

this:"Your letter greatly appreciated. Since

talking to you I have gotten the factoryto make a bunch of these sets withoutcabinets for $6.75. Send order if youwant one. You can have all parts for$5.25 or special coil for $1.00.

"As a courtesy to me, send me namesand addresses with stamps of ten friendswho would like copy of this hookup. Copyof lecture as a reference, 25c. I can ad-vise you on radio troubles. Let me hearfrom you.

"Sincerely,"H. F. VORTKAMP."

\ 1)111 \V C) R L I) October 24, 1925

Radio UniversityA QUESTION and Answer Department

coaducted by RADIO WORLD forits Readers by its staff of Experts. AddressLetters to The Radio University, RADIOWORLD, 145 West 45th St., New York City.

WILL YOU please give me a schematicdiagram of the original Thordarson-Wadehookup, which was published in the Oct.3 issue of Ramo Yoinz, New-port, R. I.

Fig. 220 shows the electrical diagram ofthe set. LI, the primary, contains 6 turnsand is wound on a tubing 3%" in diameterand 4" high, using No. 22 DCC wire asthe winding wire. The secondary L2 iswound inside, or next to the primary witha /t" separation. There are 60 turns onthe secondary. The same wire is used.The primary of the second radio -frequencytransformer contains the same number ofturns and is wound on a similar tubing,with the same diameter and height dimen-sions as was Ll. The same applies to thesecondary L4, except that it is tapped at

"0-0-15-(5

C

06D5

RI

Ormil,

were used, the signal strength would bevery small. (3) Any standard type ofloop may be used with success.

*WILL A Birco 3 -circuit tuner, when

used in connection with a Bruno Radio -Frequency Transformer give good re-sults? (2) 1 have a Philco 4 -volt storagebattery which 1 would like to use to lightthe filaments of the UV199 tubes that Iam using. Will this give me good re-sults?-B. M. Russell, 800 Bluegrass Ave.,Louisville, Ky.

(1) Yes it will be 0. K., but before put-ting them in the circuit, count the numberof turns on the primary and the second-ary and see if they are the same. In otherwords try to match the windings. Youcan use either coils as a standard. The

!;e03025

0005

11

355 -to -1 for the first stage on the Dia-mond? (3) 1 would like to purchase anSLF variable condenser. Which onewould you suggest? (4) I would also liketo purchase a first-class vernier dial. 11:i eyou any suggestions? (5) I made at homea 3 -circuit tuner for another 4 -tube setThis called for a 6 -turn primary, and a55 -turn secondary, all wound on a bakerweave form. The primary is wound onthe outside. The secondary is separatedfrom the primary winding by b" and isspaced wound. The tickler was composedof No. 24 double cotton covered wire. 1

put on 27 feet, and did not count thenumber of turns. Now, I would like touse this coil on the Diamond. Whatchanges will be necessary?-H. FrencontHolbrook, Warren, Indiana.

(1) The distance and the,- quality re-production of both these sets, if builtproperly are equal. (2) Either one willdo. (3) See our advertising columns.They are all good. (4) Consult our ad-vertising columns. (5) Increase the num-ber of turns on the primary to 10 turnsand decrease the number of turns on thesecondary to 45 turns. No. 22 double cot-ton covered wire should be used whenwinding these coils. The secondariesshould be tuned by a .0005 mfd. variablecondenser. There is no need for spacingthe windings. Instead of placing 27 feet

FIG. 220, shows the electrical diagram of the set requested by Mr. Yoinz.the 14th turn. Cl and C2 are both .0005mfd. variable condensers. C3 is a .00025mfd. variable condenser, C4, is a .00025fixed grid condenser. R3 is a variable gridleak, having a resistance of from ty to10 megohms. The auto -transformers areused as a means of coupling the audio -amplifying tubes. The coupling con-densers are as marked 25 mid. The tubesused are of the 201A type. The resistanceof RI and R2 are 10 ohms. The resistancecontrolling the amplifier tubes is of the

ampere type.* *

I HAVE a new Atwater -Kent Model 20Compact. (1) Can I use a loop and stillhear WEEI (250 miles distant), andWEAF (400 miles distant)? (2) Wouldthe loop cut out some of the interferenceand the static. (3) What type of a loopwould you advise me to get?-C. C. Good-win, care Gilman High School, ManualTraining Dept., Northeast Harbor, Me.

(1) No, you cannot use the loop withthis set and hear those distant stations.If you wish to use the loop, you will haveto do some juggling with the wires. Theprimary and the secondary of the firstRFT will have to be disconnected fromtheir respective positions, and the loopshunted across the variable condenser.This condenser originally tuned the sec-ondary of the RFT. (2) The loop wouldincrease the selectivity of the set. Staticwould be cut down to a small degree. Itwould not be cut out entirely, unless somespecial device was used. If this device

3 -circuit tuner will be much better, a,you will not have to change the ticklerwindings. (2) Yes, the set will work verywell.

IN BUILDING the 1925 3 -control Dia-mond, is it necessary that the tickler becontrolled by a vernier dial? (2) Can Iuse the Transcontinental low -loss 3 -circuittuner? (3) Can I place the antenna coilon the baseboard behind the condenser?-John C. Herbert, 1176 Conway St., St.Paul, Minn.

(1) It wouldn't hurt to have a vernierdial, although the tickler should not befound to be so critical, that would neces-sitate this. (2) Yes. (3) Yes.

KINDLY GIVE directions for windingcoils for the Powertone, using No. 18double cotton covered wire, and using thebasket weave form for winding the coilon.-A. C. Thomas, Box 91, North Bir-mingham, Ala.

There are 8 turns on the primary and 40turns on the secondary. There are 15,nokes in a circular form 3,/2" in diameter.The windings are in and out of every twospokes. That is, the winding is broughtunderneath two spokes, and then overtwo spokes.

IS THE distance and quality featureof the Thordarson-Wade set as good asthose of the Diamond? (2) Should I usea Thordarson 2 -to -1 transformer or a

135

845

F-8-Sy A

A-

oi wire on the tickler place 35 turns.The diameter of the form should be 31/5".The diameter of the tickler should be 2Ya".

*

COULD TWO stages of radio -frequencyamplification be successfully added to aregenerative detector? That is, wouldthe volume and the distance be materiallyincreased?-Wesley \V. Canfield, EastCannan, Conn.

The volume and the distance would beincreased to a very small extent.

4. 4.

COULD THE Acme D Coil be used asa radio -frequency transformer in theDiamond. I would also like to use thesame make variable condensers to shuntthe secondary. (2) Would any type of a3 -circuit tuner work 0. K.?-ThomasLyons, 68 Fairmont Ave., Newark, N. J.

(1) Yes. (2) Yes, provided the primariesand the secondaries are matched up.

I AM building the 1925 Diamond. (1)Can I use the Peanut N. E. 215 vacuumtubes in this set with success? (2) Ihave constructed this set, but have ob-tained no volume. Is this due to, the poorquality of the tubes? (3) I w 3 .nd thecoils on tubings 3,A" in diameter, usingthe same number of turns as prescribedin the text. Was the text 0. K.? (4)Would you suggest any changes in theamplifying tubes? (5) I cannot get be-low 290 meters. Please give suggestions.The selectivity of the set is excellent.-


I

H. Norman Lidster, New Westminster,B. C., Canada.

(1) The volume will be very poor, al-though the distance reception will befair. (2) Yes. (3) Yes. (4) Yes, use the201A or 199 type tubes. (5) Place a .001mfd. fixed condenser in series with theantenna. If this does not help, place an-other .001 mfd. condenser in shunt to theone already installed.

A DIAGRAM of a 1 -tube regenerativereceiver is requested. I would like tohave a switch employed, by which thegrid return could be twisted around, thatis employ the switch to either connect thegrid to the negative side of the A batteryor directly to the plate through the ticklerlead.-R. Coaxley, New Hampton, Mo.

Fig. 221, shows a diagram as requested.The primary, Ll, of the 3 -circuit tuner iswound on a tubing 3%" in diameter and4" high and contains 10 turns. There isno separation and the secondary, I2, iswound. This contains 45 turns. The wireused when winding these coils is of theNo. 22 double cotton covered type. Thetickler, L3, is wound on a tubing 2%" indiameter and 2" high. There are 35 turnswound. The wire being used is the sameas used on the primary and the second-ary. The variable condenser, Cl, is onehaving a capacity of .0005 mfd. and usuallyconsists of 23 plates. The grid condenser,C3, is one having a capacity of .00025 mfd.The grid leak is a fixed one and has aresistance of 2 megohms. The resistanceof the rheostat is 10 ohms, provided the201A type tube is used. The condenser, C3,is one having a capacity of .001 mfd. Asyou will notice this is optional. The volt-age placed on the tube is 45. Any othertype tube, such as the 199, the WD11 or12 may be used. The results as far asvolume is concerned will be much lesswith all these tubes.

* *THE and the audio tubes in a

Freshman Masterpiece receive no B bat-tery current. (1) What can this be dueto? (2) The Crosley AFT are onlymarked P and S. How shall I differenti-ate so that I may know which is which,when hooking up the AF amplifier? (3)I would like to make an A batterycharger. Would you please give me thewiring for the step-up transformer?-W.L. Bickford, Moscow, Mich.

(1) This can be due to several reasons,viz., the upper and lower terminals of thejack are not making the proper contact;there is an open or short in the primarywindings of the AFT; there is a brokenlead in the plate coil, either internally orexternally; the terminals of the tubes maynot be touching the prongs of the socket;there may be a broken lead on the B+binding post. (2) For the primary wind-ing, it does not matter, which lead is con-nected to the B+ or P, but for the sec-ondary, connect the post which holds theoutside lead of the secondary to the gridpost. The other lead goes to the F-.The P leads are the primary leads andthe S leads are the secondary leads. Ifyou .cannot see the windings, then con-nect one P post to the plate, and the Spost diagonally opposite to the G post onthe socket. (3) Such an instrumentshould be bought. There are too manywindings to wind and the type of wireused is very difficult to handle.

* *

KINDLY ADVISE me if I can employthe Ambassador 3 -circuit tuning coil inthe 3 -tube 3 -circuit tuner described byCapt. P. V. O'Rourke in the October 10issue of RADIO WORLD. (2) Canuse WD12 tubes in the set?-J. Savaese.152 Eus. 123rd St., New York City.

(11 Yes, very successfully. (2) Yes.* * *

IN THE June 27th issue of RADIOWORLD there appeared an article onBernard's 3 -circuit tuner that you can log.I would like to use .0005 mfd. variable

FIG. 221, showing the peculiar

condensers. Please advise the number ofturns to place on the coils.-Arthur L.Fields, South State St., Ripley, N. Y.

There are 10 turns on the primary, 45turns on the secondary. This is woundon a tubing 3W in diameter and 3t/2"high. The plate coil is wound on a tubing3" high and 3" in diameter. It contains35 turns. Both coils are wound with No.22 double cotton covered wire.

* *

WILL YOU please publish a diagramof the 2 -tube "Grimes Inverse Duplex?"-E. Lang, 2704 Norwood St., N. S., Pitts-burgh, Pa.

In the August 8 issue of RADIOWORLD, such a diagram with completebuilding data was given. This set caneasily be made into a 3 -tube affair byinserting an extra audio -stage, the topof the jack which comes from the plateof the first tube, goes to the P post ofthe AFT and the bottom post going tothe B plus post.

* *

KINDLY LET me know if I can usethe Bremer Tully 3 -circuit tuner, theradio -frequency transformer, and the vari-able condenser in the 4 -tube Diamondwith success ?-Chas. Fisher, 337 SecondAve., Garwood, N. J.

Yes.* * *

I WOULD like to build the Diamond.I have one 90° coupler and one 180°coupler. (1) Which one is advisable tobe used? (2) What are the number ofturns to place on the secondary of eithercoupler? (3) How many turns are to he

C3

diagram requested by Mr. Coaxley.

placed on the primary ? (4) What spaceis left between the primary and the sec-ondary? (5) How many turns are placedon the rotor? (6) Will the Acme A-2transformer be all right for the audio -stages ?-Robert Kemey, 85 Magnolia St.,Dorchester 25, Mass.

(1) It does not matter which one isused, although the 180° coupler gives alittle more variation. (2) There are 10turns on the priMary, the tubing being ..3t/2" in diameter and 4" high. There are45 turns on the secondary, this beingwound on the same tubing. (4) Thereis no spacing between the primary andthe secondary windings. (5) There are35 turns in the rotor, this usually beingcalled the tickler. The diameter of thistubing is 2/2" and the height is 2". (6)Yes.

I WOULD like to know how manyturns I would have to have on a 3 -circuitcoil which will tune from 200 to 450meters. Also please state the diameterof the tubing.-Ernest G. Emond, 268Cornelia St., Brooklyn, N. Y.

There are 8 turns on the primary and35 turns on the secondary. This is woundon a tubing 3,4" in diameter and 4" high.The tickler is wound on a tubing 2/2" indiameter and 2" high. There are 25 turnsplaced on here. No. 22 double cotton cov-ered wire is used for winding all the coils.

If you wish to receive signals on higherwavelengths, i.e., to 550, use a 10 -turnprimary and a 45 -turn secondary. Thetickler should have 35 turns in conjunc-tion with the 10 -and -45 inductancec.

* * *

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16 RADIO \WORLD October 24, 1925

The Bernard 1 -Tube DX SoLocal Stations Are Not

Tuned Out By Variationof the Regeneration Con-trol, Which, While Some-what Sharp for the VeryLow Broadcast Waves,Is Not a Bit Critical Over400 Meters - FeedbackCondenser Even CouldBe of the NeutralizingType, Says Author.

By Herman BernardAssociate, Institute of Radio Engineers

PART I.A1 -TUBE set that is readily adaptable

to parts that may be lying aroundthe house, and which uses only a single

coil, or fixed coupler,is shown in Fig. 1.Its advantages in-clude the simplicityof making the coil,due to the absence ofa rotary tickler,which would intro-duce mechanical dif-ficulties; the use of a

condenserfor feedback, whichtakes away much ofthe criticalness pres-

HERMAN ent in rotary ticklerBERNARD coil feedback, and the

utter simplicity of the construction.The set is capable of getting distance

on a par with the rotary tickler type ofregenerative circuit, for indeed all theregenerative hookups, where only one tubeis employed and crystal or reflex avoided,may be expected to perform about atpar. The variations, in point of perform-ance, depend not so much on the hook-up as on the parts used and the methodof wiring.

The Feedback CondenserOne point about this set is the possibil-

ity of the feedback condenser having aneffect upon the wavelength tuning con-denser, Cl, so that compensated tuningmay exist to a slight extent. This com-monly would denote the use of too largea feedback condenser, C2. Just what ca-pacity this condenser should be will de-pend largely on the point at which thetap T is taken on the secondary. Wherethe tap is taken at a point about one-quarter from the low potential end of the

TOP VIEW of the 1 -tube set.

B

B

+AFIG. 1, the electrical wiring diagram of the Bernard 1 -tube DX set, shownschematically. The coils are drawn in such fashion as to clarify the manner ofconnecting their terminals and the tap T. Regeneration is supplied by the Hartleyoscillator hookup, the same system as used by Bernard in the Thordarson-Wade5 -tube set. Note that the rotors of both Cl and C2 are connected to the same leadthat goes to the beginning of the secondary L2, and this lead connects nowhere else.

coil, granting 12 is tuned by a .00035mfd. variable, the capacity of a shouldbe no more than .00025 mfd., and may beeven .0001 mfd. However, it is not soeasy to get a .0001 mfd. variable, and fewexperimenters will have such an instru-ment handy around the house, ready toput into the set. Therefore, the tapshould be taken still nearer the begin-ning of the coil. Indeed, if the tap wereplaced much nearer the grid it would bepossible to control regeneration with aneutralizing condenser, but the objectionto that is, of course, the peril of bypass-ing (i. e., virtually short-circuiting) theinput, in which case you would receiveno signals.

Compared With Tuned PlateHowever, the regeneration control meth-

od here set forth is one that affords finesmoothness and differs from the tunedplate method largely in that the conden-ser capacity should be much smaller thanotherwise and there is no utter dependenceon the whimsicalities of the tube. Thetuned plate method consists of a coil con-nected between plate and one of the phonetips, a variable condenser being usedacross this coil. The inductance is usuallyabout the same as that on the secondary(12 in this case), and the condenser ofthe same capacity as the one tuning thesecondary. While this enhances the pos-sibility of the regeneration condenser tun-ing in step with the other, the great diffi-culty with this form of hookup is thatsome tubes are not over eager to transferthe plate current back to the grid circuitthrough the inter -electrode capacity ex-isting inside the tube, between grid andplate. The capacity often is too small toinsure success, for an actual condenserexists within the tube, and it is an un-certain factor. One has to depend muchon the relative position of grid and plateinside the tube, which the manufactureralone might have discovered, but whichknowledge th epurchaser necessarily mustbe denied. And even if it were given tohim, what good would it be?

To obtain regeneration by the tuned

plate method it is commonly necessary toput a fixed bypass condenser, normally.001 mfd., across the phones, or, in anaudio amplifying circuit, across the pri-mary of the first audio -frequency trans-former. This condenser should not benecessary, but when it is necessary it sim-ply has to be there or you have a setthat, for sheer performance, does not out-rank a simple crystal set. Of course in anaudio amplifying circuit the bypass con-denser may become additionally necessarybecause the radio currents should be keptout of the transformer primary.

When the tuned plate circuit works wellthe set is a fine one, but many personswho have built such a set report no greatsucess, although a much greater numberhave succeeded. For general use, there-fore, it would see madvisable to have acircuit that is more dependable on a quan-tity production basis. Such a set is shownin Fig. 1.

The Hartley oscillator system is used forobtaining regeneration. The plate cur-rent, instead of being put into the phonesexclusively, is separated as to its radio andaudio components, the radio componentbeing returned to the grid through the re-generation condenser, while the audio cur-rent passes into the phones, actuatingthem, so that you can hear the broadcastprogram. As a serves also a bypass pur-pose there is no need for a fixed bypasscondenser in the circuit. It is always wellto dispense with fixed condensers, wherethat is possible, most especially when theyare used in the radio side of a circuit,for all the care of selection of low -lossinstruments and in actual set constructioncomes to naught when a high -loss fixedcondenser is introduced.

An Inexpensive SetThe set I am describing, however, is not

intended to be one on which you willspend any real money. I do not think thatany one should go to real expense in build-ing a 1 -tube set. Rather, it is assumedthat there is a receiver in the home thatworks a speaker, but that the experimenteror the DG hound wants something else,


for Novice an d Expert Alike

THE REAR VIEW of the set, showing the tap lead that goes to A+.

LIST OF PARTSONE 7a12 PANEL.ONE RADIO -FREQUENCY TRANS-

FORMER, 111.2.ONE .00035 mfd.

DENSER, Cl.ONE .00025 mfd.

DENSER, C2.ONE 30 -ohm RHEOSTAT.TWO 3 DIALS.TWO DIAL POINTERS.ONE SINGLE -CIRCUIT JACK.ONE .00025 mfd. GRID CONDENSER,

C3.ONE 2-megohm FIXED GRID LEAK.ONE STANDARD NAVY BASE

SOCKETONE 1x13 BASEBOARD, UNLESS

PANEL -MOUNT METHOD IS USED.

VARIABLE CON -

VARIABLE CON -

which he can use after the folks are goneabed, or when he's alone in the house, andfor that purpose will resuscitate parts fromthe sets and circuits of other days, andfrom this heap of quasi -discard fish forththe parts with which to appease his ex-perimental desires or appetite for the re-ception of distant stations. The idea ofusing spare parts, or very inexpensive ones,if any are to be purchased, was a funda-mental one.

The CoilTake the coil as an example. It may

be a neutroformer. This, you know, is thename given to a fixed coupler with a tapon it for neutralizing purposes. Wherethis tap will be found no one can deter-mine as a certain proposition, but it hasbeen common to put the tap at a pointrrepresenting the same equivalent amounto inductance that is in the primary. Nomatter where the tap may be you can

THE PANEL VIEW of the set, withthe engravings designating the instru-ments.

make your own tap for your own purposeby lifting one of the turns 1/8 -inch fromthe form, using a penknife, scraping off theinsulation and soldering a flexible insu-lated lead or other piece of wire to thispoint.

The location of the tap as near begin-ning of 12 is clarified by a glance at Fig.2, which shows the wiring in picture form.As the coil stands upright it will be seenthat the aerial is connected to the top ter-minal of the primary 12. The ground isjoined to the bottom end of the primary.Now, instead of the adjoining terminalof the secondary, i. e., top terminal of thatwinding, going to grid condenser, as isoften done in 1 -tube hookups, it goes tothe rotor plates of both variable conden-sers, Cl and C2, and is connected to noother part or point. In other words, thewhole secondary 12 is tuned by the con-denser Cl, but the grid input voltage isderived from only that part of the secon-dary that lies between the tap and thegrid end. The small number of turns be-tween the tap and the rotary plate con-nection (beginning of L1) is really in theplate circuit, as can be seen by followingthe plate radio output to the stator platesof C2, to the rotor plates of C2 and on tothe beginning of 12.

Coil is in SeriesCondenser C2, therefore, is in series with

the winding between T and the beginningof 12. That is why the inductance in thatsmall part of the secondary 12, i. e., thelocation of the tap, determines the max-imum capacity necessary for C2, or, viceversa, why almost any available capacityvariable condenser may be used for C2,simply by shifting the tap point, so thatit is farther from the plate end of the coilfor smaller capacity condenser and nearerto the plate end for larger capacity con-denser. Under no circumstances need avariable condenser larger than .0005 mfd.be used for C2, and this should not beemployed unless it happens to be the onlyone handy. The admonition is not im-oortant enough to make any one hesitateabout using the .0005 mfd., however. ifthat it what he has.

The primary winding, LI, in any casewould be the same for a given diameter,no matter what capacity C2 or even Clmight be. Assuming that a .00035 mfd.condenser is to be used for Cl, and the

Simplicity of Coil Wind-ing, Ease of Regenera-tion Control, and Gen-e r a 1 Adaptability t oParts Lying Around theHouse Characterize ThisCircuit - Hartley Oscil-lator Method Used forRegeneration Supply -Set Can Be Made toPress Any Values ofVariable Condensers In-to Use.

tubing or other form is to be 31,6"diameter, the ?vire No. 20 single cottoncovered, put on 10 turns for 12, leave14" space, wind 60 turns for the secondary,but be sure to tap the secondary. Locatethe tap according to the value of C2.

A Variable FactorSome variations may be expected, even

if the following data are observed, never-theless it is a good general rule to locatethe tap at the eighth turn if C2 is to be.00025 mfd. and at the fourth turn if it isto be .00035 mfd. That may seem in-ordinately low but it proved to be rightin several tests that I made. If you havea .0001 mfd. variable condenser, normallyseven plates, then locate the tap at thetenth turn.

The tap position, lest I have not madethis perfectly clear, in a home-made coilshould be at the specified turn from thebeginning of the secondary winding. Forinstance, suppose you are putting on a60 -turn secondary. Suppose C2 is to be.00025 mfd. Then wind eight turns, twistthe wire into a small loop, and wind 56turn more turns, thus completing thesecondary. Scrape a little insulation offthe tap for connection. The beginninggoes to the common rotors, the end tothe coil side of the grid condenser, whilethe tap goes to A plus. If the tap on acommercial coil is near the end of 1.2,connect rotors to end, beginning to gridcondenser, tap to A plus. If a UV200 orSodion D21 tube is used this tap in eithercase should go to A minus. The Sodiontube, by the way, is not being manufac-tured any more by the Connecticut Tele-phone and Telegraph Company, and is dis-appearing from the market.

[Part II, the conclusion of this article onhow to build the Bernard 1 -tube set, willbe published next week, issue of Octo-ber 31.]

BOTTOM VIEW of the receiver, whichwas made without baseboard, thus

necessitating a panel -mount socket.


THE KEY TO THE AIRKEY

Abbrevationsi EST, Eastern Standard Time;...ST, Central Standard Time; MST MountainStandard Time; PST, Pacific Standard Time;

How to tune in a desired distant station at baitthe right time -Choose your station from thelist published herewith. See what time divisionthe staton a under (EST, CST, etc.); then con-sult the table below. Add to or subtract, as di-rected from the time as given on the PROGRAM.The result will be the same BY YOUR CLOCKthat you should tune in, unless daylight savingtime intervenes, as explained below.-Ths tablet

If Y.sare isESTESTESTCSTCSTCSTMSTMSTMSTPSTPSTPST

Subtract

1

Odd1 hr.2 hrs.3 hr..

1 hr.2 hrs.

2 bra.

1 hr.1 WI..

3 Wig.2 hrs.1 hr.

FRIDAY, OCTOBER 23

And want astation its

CSTMSTPSTESTMSTPSTESTCSTPSTESTCSTDST

WAAM, Newark, N. J., 263 (EST) -11 AM to 12;7 PM to 10:30.

WAHG, Richmond Hill, N. Y., 316 (EST) -12:30 to1:05 PM; 7:30 to 11:05 PM.

WAMD, Minneapolis, Minn., 243.8 (CST), -12 to 1P111, 10 to 12.

WBBM Chicago, Ill. 226 (CS T)=8 to 10 PM.WBBR, New York City, 272.6 (EST) -8 PM to 10.WBOQ, Richmond Hill, N. Y., 236 (EST) -7:30

PM to 11:30.WBZ, Springfiedl, Mass., 333.1 (EST) -6 PM to 11.WCCQ, St. Paul and Minneapolis, Minn., 416.4

(CST) -9:30 AM to 12 M; 1:30 to 4, 5:30 to 10.WCAE, Pittsburgh, Pa., 461.3 (EST) -12:30 to

1:30 PM; 4:30 to 5:30; 6:30 to 11.WDAF, Kansas City, Mo., 365.6 (CST) -3:30 to

7 PM; 8 to 10 11:45 to 1 AM.WEAF, New York City, 492 (EST) -6:45 AM to

7:45; 11 to 12; 4 PM to 5; 6 to 12.WEAR Cleveland, 0., 390 (EST) -11:30 AM to

12:10 PM; 3:30 to 4:10; 8 to 11.WEAO, Ohio State University, 293.9 (EST) -8

PM to 10.WEEL Boston, Mass., 476 (EST) -6:45 AM to

7:45; 2 PM to 3:15; 5:30 to 10.WEMC. Berrien Springs, Mich., 286 (CST) -9 PM

to 11.WFAA, Dallas, Texas, 475.9 (CST) -10:30 AM to

11:30; 12:30 I'M to 1; 2:30 to 6; 6:45 to 7; 8:30to 9:30.WPBH, New York City, 272.6 (EST) -2 PM to 6.

WGBS, New York City, 316 (EST) -10 AM to11; 1:30 PM to 4; 6 to 7:30.

WGCP, New York City, 252 (EST) -2:30 PM to.5:15;' 8 to 11.

WGES Chicago, 250 (CST) -7 to 9 PM; 11to 1 AM.

WGN, Chicago, Ill., 370 (CST) -9:31 AM to 3:30PM; 5:30 to 11:30.

WGR, Buffalo, N. Y., 319 (EST) -12 M to 12:45PM: 7:30 to 11.

WGY, Schenectady, N. Y., 379.5 (EST) -1 PM to2; 5:30 to 10:30.

WHAD, Milwaukee, Wis., 275 (CST) --11 AM to12:15 PM; 4 to 5; 6 to 7:30; 8:30 to 10.

WHAS, Louisville, Ky., 399.8 (CST) -4 PM to 5;7:30 to 9.

WHN, New York City, 360 (EST) -12:30 PM to1; 2:15 to 5; 7 to 11; 12 to 12:30 AM.

WHO, Des Moines, Iowa, 526 CST) -7 PM to 9;11 to 12; 12:30 to 1:30; 4:30 to 5:30; 6:30 to 9:30.

WHT, Chicago, EL, 400 (CST). -11 AM to 2 PM;7 to 8:30; 8:45 to 10:05; 10:30 to 1 AM.

WIP, Philadelphia, Pa., 508.2 (EST) -6:45 AM to7:15; 10 to 11; 1 PM to 2; 3 to 5; 6 to 7.

WJY, New York City, 405 (EST) -7:30 PM to11:30.

WJZ, New York City, 455 (EST) -10 AM to 11;1 PM to 2; 4 to 6; 7 to 10:30.

WLIT, Philadelphia, Pa., 395 (EST) -12:02 PMto 12:30; 2 to 3,1i 4:30 to 6; 7:30 to 1 AM.

WLW, Cincinnati, 0., 422.3 (EST) -10:45 AM to12:15, 1:30 to 2:30.

WMCA, New York City, 341 (EST) -11 AM to12 M; 6:30 PM to 12.

WNYC, New York City, 526 (EST) -3:45 PM to4:45; 6:20 to 11.

WOAW, Omaha, Neb., 526 (CST) -12:30 PM to 1;5:45 to 7:10; 9 to 11.

WOC, Davenport, Iowa, 484 (CST) -12:57 PM to2, 3 to 3:30; 5:45 to 12.

WOR, Newark, N. J., 405 (EST) -6:45 AM to7:45; 2:30 PM to 4; 6:15 to 7.

WPAK, Fargo, N. D. 283 (CST) -7:30 PM to 9.WPG, Atlantic City, N. J., 299.8 (EST) -7 PM to

8:30; 10 to 12.WQJ Chicago, Ill., 448 (CST) -11 AM to 12 M;3 PM to 4; 7 to 8; 10 to 2 AM.

WRC, Washington, D. C., 469 (EST) -9 AM to10; 12 PM to 1; 5 to 7.

WREO, Lansing, Michigan, 285.5 (EST) -10 PMto 11.

WRNY, New York City, 258.5 (EST) -11:59 to2 PM; 7:59 to 9:45.

WSB, Atlanta, Ga., 428.3 (CST) -12 M to 1 PM;2:30 to 3:30; 5 to 6; 8 to 9; 10:45 to 12.

WSBF, St. Louis, Mo., 273 (CST) -12 M to 1 PM;3 to 4; 7:30 to 10; 12 PM to 1 AM.

WWJ, Detroit, Mieh., 352.7 (EST) -8 AM to 8:30;9:30 to 10:30; 11:55 to 1:30; 3 to 4; 6 to 7;8 to 10.

KDKA, Pittsburgh, Pa., 309 (EST) -6 AM to 7;9:45 to 12:20 PM; 1:30 to 3:20; 3:30 to 11.

KFAE, State College of Wash., 348.6 (PST) -7:30PM to 9.

KFDY. Brookings, S. D., 273 (MST) -8 PM to 9.KFL Los Angeles, CaL, 467 (PST) -5 PM to 10.KFKX, Hastings, Neb., 288.3 (CST) -12:30 PM to

1:30; 9:30 to 12.KFNF, Shenandoah, Iowa, 266 (CST) -12:15 PM

to 1:15; 3 to 4; 6:30 to 10.KFOA, Seattle, Wash., 455 (PS7)-12:30 PM to

1:30; 4 to 5:15; 6 to 11.EGO Oakland, CaL, 261.2 (PST) -11:10 AM to 1

P11; 1:30 to .; 4 to 7.KGW, Portland, Ore iron, 491.5 (PS1)-11:30 AM to

1:30 PM; 5 to 11.KHJ. Los Angeles, Cal., 405.2 (PST) -7 AM to

7:15; 12 M to 3:30 PM; 5:30 to 11:30.RJR, Seattle, Wash., 484.4 (PST) -10:30 AM to

11:30 AM; 1 PM to 6:30; 8:30 to 11.KNX, Hollywood, CaL, 337 (PST) -11:30 AM to

12:30 PM; 1 to 2; 4 to 5; 6:30 to 12.KOA, Denver, OIL, 322.4 (MST) -11:45 AM to

12:30 PM; 330 to 4:15; 6 to 10.BOB, State College of New Mexico, 348.6 (MST) -

11:55 AM to 12:30 PM; 7:30 to 8:30; 9:55 to 10:10.KOIL, Council Bluffs, Iowa, 278 (CST) -7:30 PM

to 8:45; 11 to 12 M.KPO, San Francisco, Cal., 429 (PST) -7:30 AM to

8; 10:30 to 12 M; 1 PM to 2; 4:30 to 11.KSD, St. Louis, Mo., 545.1 (CST) -4 PM to 5.KTHS, Hot Springs, Ark., 374.8 (CST) -12:30 PM

to 1; 8:20 to 10.KYW, Chicago, Ill., 536 (CSTDS)-6:30 AM to

7:30; 10:55 to 1 PM; 2:25 to 3:30; 6:02 to 7:20;9 to 1:30 AM.

CNRA, Moncton, Canada, 313 (EST) -8:30 PM to10:30.

CLARE, Edmonton, Canada, 516.9 (MST) -8:30 PMto 10:30.

CNRS, Saskatoon, Canada, 400 (MST) -2:30 PMto 3.

CNRT, Toronto, Canada, 357 (EST) -6:30 PM to11.

SATURDAY. OCTOBER 24WAAM, Newark, N. 7., 263 (EST) -7 PM to 11.WAHG, Richmond Hill N. Y., 316 (EST) -12:30

PM to 1:05; 12 to 2 AM.WAMD, Minneapolis, Minn., 243.8 (CST) -12 M

to 1 PM; 10 to 12.WBBM, Chicago, Dl., 226 (CST) -8 PM to 1 AM.WBBR, New York City, 272.6 (EST) -8 PM to 9.WBOQ, Richmond Hill, N. Y., 236 (EST) -3:30

PM to 6:30.WBZ Springfield, Masa., 333.1 (EST) -11 AM to

12:30 PM; 7 to 9.WCAE, Pittsburgh, Pa., 461.3 (EST) -10:45 AM

to 12 M; 3 PM to 4; 6:30 to 7:30.WCBD, Zion, DL, 344.6 (CST) -8 PM to 10.WCCO, St. Paul and Minneapolis, Minn., 416.4(CST) -9:30 AM to 12:30 PM; 2:30 to 5; 6 to 10.WEAF, New York City, 492 (EST) --6:45 AM to

7:45; 4 PM to 5, 6 to 12.WEE, Boston, Maas., 476 (EST) -6:45 AM to

7 AM.WEAR, Cleveland, 0., 390 (EST) -11:30 AM to

12:10 PM; 3:30 to 4:10; 7 to &WEMC, Berrien Springs, Mich., 286 (CST) -11

AM to 12:30 PM; 8:15 to 11.WFAA, Dallas, Texas, 475.9 (CST) -12:30 PM to

1; 6 to 7; 8:30 to 9:30; 11 to 12:30 AM.WFBIL New York City, 272.6 (EST) -2 PM to

7:30: 11:30 to 12:30 AM.WGBS, New York City, 316 (EST) -10 AM to

11; 1:30 PM to 3; 6 to II.WGCP, New York City, 252 (EST) -2:30 PM

to 5:15.WGES, Chicago, Ill., 250 (CST) -7 PM to 9; 11

to 1 AM.WGN, Chicago, EL, 370 (CST) -9:31 AM to 2:30

PM; 3 to 5:57; 6 to 11:30.WGY, Schenectady, N. Y., 379.5 (EST) -7:30 PM

to 30.WHAD, Milwaukee, Wis., 275 (CST) -11 AM to

12:30 PM; 4 to 5; 6 to 7:30.WHAR, Atlantic aty, N. J., 275 (EST) -2 PM

to 3; 7:30 to 9.WHAS, Louisville, Ky., 399.8 (CST) -4 PM to 5;

7:30 to 9.WHN, New York City, 360 (EST) -2:15 PM to

5; 7:30 to 10.WHO, Des Moines, Iowa, 526 (CST) -1I AM to

12:30 PM; 4 to 5:30; 7:30 to 8:30.WHT, Chicago, DL, 400 (CST) -11 AM to 2 PM;

7 to 8:30; 10:30 to I AM.WIP, Philadelphia, Pa., 508:2 (EST) -7 AM to

8; 10:20 to 11; 1 PM to 2; 3 to 4; 6 to 11:30.WJY, New York City, 405 (EST) -2:30 PM to

5: 8 to 10:30.WJZ, New York City, 455 (EST) -9 AM to 12:30

PM; 2:30 to 4; 7 to 10.WRAC, Cincinnati, 0., 326 (EST) -10 to 12 M.WLWC, Cincinnati, 0., 422.3 (EST) -9:30 AM to

12:30 PM; 7:30 to 10.WMAK, Lockport, N. Y., 265.5 (EST) -10:25 AM

to 12:30 PM.WMCA, New York. City, 341 (EST) -3 to 5 PM;

6:30 to 2.WNYC, New York City, 526 (EST) -1 to 3 M;

7 to 11.WOAW,. Omaha, Neb., 526 (CST) -10 AM to 1;

2:15 to 4; 9 to 11.WOC, Davenport, Iowa, 484 (CST) -12:57 PM to

2; 5:45 to 7:10; 9 to 12.WOO, Philadelphia, Pa., 508.2 (EST) -11 AM to

1 PM; 4:40 to 5; 10:55 to 11:02.WOR, Newark, N. 7.. 405 (EST) -6:45 AM to

7:45; 2:30 PM to 4; 6:15 to 7:30; 8 to 11.

WQJ, Chidago, Ill., 448 (CST) -11 AM to 12 M;3 PM to 4; 7 to 8; 10 to 3 AM.

WPG, Atlantic City, N. J., 299.8 (CST) -7 PMto 12.

WRC, Washington, D. C., 469 (EST) -1 PM to 2;6:45 to 12.

WREO, Lansing, Mich., 285.5 (EST) -10 PM to 12.WRNY, New York City, 258.5 (EST) -11:59 to

2 PM; 7:59 to 9:30; 12 M to I AM.WSB, Atlanta, Ga., 428.3 (CST) -12 M to 1 PM;

3 to 4; 5 to 6; 10:45 to 12.WWJ, Detroit, Mich., 352.7 (EST) -8 AM to 8:30:

9:30 to 10; 11:55 to 1:30 PM; 3 to 4.KDKA, Pittsburgh, Pa., 309 (EST) -10 AM to

12:30 PM; 1:30 to 6:30: 8:45 to 10.KFI, Los Angeles, Cal., 467 (PST) -5 PM to 11.KF1X, Hastings, Neb., 288.3 (CST) -12:30 PM to

1:30; 9:30 to 12:30.KFNF, Shenandoah, Iowa, 268 (CST) -12:15 PM

to 1:15; 3 to 4;,

6:30 to 10:30.KFOA, Seattle, Wash. 455 (PST) -Silent.KGO, Oakland, CaL, 361.2 (PST) -11 AM to 12:30

PM; 3:30 to 5:45; 7:30 to 9.KGW, Portland, Oregon, 491.5 (PST) -11:30 AM

to 1:30 PM; 6 to 7; 10 to 11.KHJ, Los Angeles, Cal., 405.2 (EST) -7 AM to

7:30; 10 to 1:30 PM; 2:30 to 3:30; 5:30 to 2 AM.RJR, Seattle, Wash., 484.4 (PST) -1 PM to 2:45;

6 to 6:30; 8:30 to 10.KNX, Hollywood, CaL, 337 (PST) -1 PM to 2;

6:30 to 2 AM.KOA, Denver, Colo., 322.4 (MST) -11:30 AM to

1 PM; 7 to 10.KOIL, Council Bluffs, Iowa, 278 (CST) -7:30 PM

to 9.KPO. San Francisco, Cal., 429 (PST) -8 AM to

12 M; 2 PM to 3; 6 to 10.KSD, St. Louis, Mo., 545.1 (CST) -7 PM to 8:30.KTHS, Hot Springs, Ark., 374.8 (CST) -12:30 PM

to 1; 8:30 to 10:30.KYW, Chicago, Ill., 536 (CST) -11 AM to 12:30

PM, 4 to 5; 7 to 8.CKAC, Montreal, Canada, 411 (EST) -4:30 PM

to 5:30.CNRO, Ottawa, Ontario, Canada. 435 (ES7)-7:30

PM to 10.PWX, Havana, Cuba, 400 (EST) -8:30 PM to 11:30.

SUNDAY, OCTOBER 25WBBM, Chicago, DI., 226 (CST) -4 PM to 6; 8

to 10.WBBR:, New York City. 272.6 (EST) -10 AM

to 12 9 PM to 11.WCCO, St. Paul and Minneapolis, Minn., 416

(CST) -11 AM to 12:30 PM; 4:10 to 5:10; 7:20to 10.

WDAF, Kansas City, Mo., 365.6 (CST) -4 PMto 5:30.

WEAF, New York City, 492 (EST) -3 PM to5; 7:20 to 10:15.

WEAR, Cleveland, 0., 390 (EST) -3:30 PM to 5;7 to 8; 9 to 10.

WFBH, New York City, 272.6 (EST) -5 PMto 7.

WGBS, New York City, 316 (EST) -3:30 PM to4:30; 8 to 10.

WGCP, New York City, 252 (EST) -8 PM to 11.WGES, Chicago, Ill., 26.0 (CST) -5 PM to 7; 10:30

to M.WGN12, Chicago, Dl., 370 (CST) -11 AM to 12:45

PM; 2:30 to 5; 9 to 10.WGR, Buffalo, N. Y., 379.5 (EST) -9:30 AM;

7:15 to 8 PM.WGY, Schenectady, N. Y., 379.5 (EST) -9:30 AM

to 12:30 PM; 2:35 to 3:45; 6:30 to 10:30.WH4:1A5D, Milwaukee, Wis., 275 (CST) -3:1S PM to

WHAR, Atlantic City, N. J., 275 (EST) -2:30 P/16to 3:45; 7:50 to 10; 11:15 to 12.

WHN, New York City, 360 (EST) -1 PM to1:30; 3 to 6; 10 to 12.

WHT, Chicago, El., 238 (CST) -9:30 AM to1:15 PM; 5 to 9.

WIP, Philadelphia, Pa., 508.2 (EST) -10:45 AMto 12:30 PM; 4:15 to 5:30.

WJZ, New York City, 455 (EST) -9 AM to12:30 PM; 2:30 to 4; 7 to 11.

WKRC, Cincinnati, 0. 326 (EST) -6:45 PM to ILWMCA, New York City, 341 (EST) -11 AM to

12:15 PM; 7 to 7:30.WNYC, New York City, 526 (EST) -9 PM

to 11.WOCL, Jamestown, N. Y., 275.1 (EST) -9 PM

to 11.WOO, Philadelphia, Pa., 508.2 (EST) -10:45 AM

to 12:30 PM; 2:30 to 4.WPG, Atlantic City, N. J., 209.8 (EST) -3:15

PM to 5; 9 to 11.WQJ, Chicago, El., 448 (CST) -10:30 AM to 12:30

PM; 3 PM to 4; 8 to 10.WREO, Lansing, Michigan, 285.5 (EST) -10 AM

to 11

WRNY, New York City, 258.5 (EST) -3 PM5; 7:59 to 10.WBF, St. Louis Mo., 273 (CST) -9 to 11 PM.WWJ, Detroit, Mich., 352.7 (EST) -11 AM to

12:30 PM; 2 to 4; 6:20 to 9.KDKA, Pittsburgh Pa., 309 (EST) -9;45 AM tc

10:30; 11:55 to 12 M; 2:30 PM to 5:30; 7 to 11.KFNF, Shenandoah, Iowa, 266 (CST) -10:45 AM

to 12:30 PM; 2:30 to 4:30; 6:30 to 10.KOA, Denver, Col., 322.4 (MST) -10:55 AM to 1PM; 4 PM to 5:30; 7:45 to 10.ROIL, Council Bluffs, Iowa, 278 (CST) -11 AM to

12:30 PM; 7:30 to 9.KGW, Portland, Oregon, 491.5 (PST) -10:30 AM

to 12:30 PM; 6 to 9.KHJ, Los Angeles, Cal., 405.2 (EST) -10 AMto 11:30 PM; 6 to 9.RJR, Seattle, Wash., 384.4 (PST) -11 AM to 12:30

PM 3 to 4:30; 7:15 to 9.KTHS, Hot Springs, Aik., 374.8 (CST) -11 AM to

12:34 PM; 2:30 to 3:40; 8:40 to 11.

October 24. 1925 RADIO WORLD 19

MONDAY, OCTOBER 26WAAM, Newark, N. J., 263 (EST) -11 AM to

12 Id; 7 PM to 11.WANG, Richmond Hill, N. Y., 316 (ESTDS)-12:30

M to 1:05 PM; 7:30 to 12.WAMB, Minneapolis, Minn., 243.8 (CST) -10 PM

to 12.WBBM, Chicago, Ill., 226 (CST) -6 PM to 7.WBBR. New York City, 272.6 (ESTDS)-8 PM

to 9.WBZ, Springfield, Mass., 333.1 (EST) -6 PM

11:30.WCAE, Pittsburgh, Pa., 461.3 (EST) -12:30 PM

to 1:30; 4:30 to 5:30; 6:30 to 12.VVCBD, Zion, DL, 344.6 (CST) -8 PM to 10.WCCO, St. Paul and Minneapolis, Minn., 416

(CST) -9:30 AM to 12 M, 1:30 PM to 6:15.WDAF, Kansas City, Mo., 365.6 (CST) -3:30

PM to 7; 8 to 10; 11:45 to 1 AM.WEAF, New York City, 492 (EST) -6:45 AM

to 7:45; 4 PM to 5; 6 to 11:30.WEAR, Cleveland, O., 300 (EST) -11:30 AM to

12:10 PM; 3:30 to 4:10; 7 to 8.WEE', Boston, Mass., 476 (EST) -6:45 AM to8; 3 PM to 4; 5:30 to 10.

WEMC, Berrien Springs, Mich., 286 (CST) -8:15PM to 11.

WFAA, Dallas Teems, 475.9 (EST) -10:30 AM to11:30; 12:30 15M to 1; 2:30 to 6; 6:45 to 7; 8:30to 9:30.

WFBH, New York City, 272.6 (EST) -2 PMto 6:30.

WGCP, New York City, 252 (EST) -2:30 PM11; 1:30 to 3:10; 6 to 7:30.

WGES, Chicago, Ill., 250 (CST) -5 PM to 8.WGCP, New York City, 252 (EST) -2:30 PM

to 5:18; 8 to 10:45.WGN, Chicago, 111., 370 (CST) -9:31 AM to 3:30

PM; 3:30 to 5:57.WGR, Buffalo, N. Y., 319 (EST) -12 M to 12:30

PM; 2:30 to 4:30; 7:30 to 11.WGY, Schenectady, N. Y., 379.5 (EST) -1 PM to

2; 5:30 to 8:30.WHAD, Milwaukee, Wis., 275 (CST) -11 AM to

12:15 PM; 4 to 5, 6 to 7:30; 8 to 10.WHAR, Atlantic City, N. J., 275 (EST) -2 PM to

3; 7:30 to 9.WHAS, Louisville, Ky., 399.8 (CST) -4 PM to 5;

7:30 to 9.WHN, New York City, 360 (EST) -2:15 PMto 5; 6:30 to 12.

WHO, Des Moines, Iowa, 526 (CST) -12:15 PM to1:30; 7:30 to 9; 11:15 to 12.

WHT, Chicago, DL, 400 (CST) -11 AM to 2PM; 7 to 8:30; 10:30 to 1 AM.

WIP, Philadelphia, Pa., 503.2 (EST) -7 AM to8; 1 PM to 2; 3 to 8.

WJZ, New York City, 455 (EST) -10 AM to 11;I PM to 2; 4 to 5:30; 6 to 6:30; 7 to 11.

WKRC, Cincinnati, 0., 326 (EST) -8 PM to 10.WLIT, Philadelphia, Pa., 395 (EST) -12:02 PM

to 1; 2 to 3; 4:30 to 6; 7:30 to 11:30.WLW, Cincinnati, O. 422.3 (EST) -10:45 AM to

12:15 PM; 1:30 to 2:30; 3 to 5; 6 to 10.WMAK, Lockport, N. Y., 265.5 (EST) -8 PM to 12WMCA, New York City, 341 (EST) -11 AM to

12 M; 6:30 PM to 12.WNYC, New York City, 526 (EST) -3:15 PM

to 4:15; 6:20 to 11.WOAW, Omaha, Neb., 526 (CST) -12:30 PM to

1.:0; 5:45 to 10:30.WO,, Davenport, Iowa 484 (CST) -12:57 PM to

; 3 to 3:30; 5:45 to 6.WOO, Philadelphia, Pa., 508.2 (EST) -11 AM

tc 1 PM; 4:40 to 6; 7:30 to 11.WOR, Newark, N. J., 405 (EST) -6:45 AM to

7:45. 2:30 to 4; 6:15 to 11:30.WPAK Fargo, N. D., 283 (CST) -7:30 PM to 9.WPG, Atlantic City N. J., 299.8 (EST) -7 PM

to 11.WOJ, Chicago, Ill., 488 (CST) -11 AM to 12 M;

3 PM to 4.WRC, Washington, D. C., 469 (EST) -9 AM to

10; 12 M to 2; 6:15 PM to 6:30.WREO, Lansing, Michigan, 285.5 (EST) -10 PM

to 11.WRNY, New York City, 258.5 (EST) -11:59 AM

to 2 PM; 7:30 to 11.WSB, Atlanta, Ga., 428.3 (CST) -12 M to 1 PM;

2:30 to 3:30, 5 to 6; 8 to 9; 10:45 to 12.WSBF, St. Louis, Mo., 273 (CST) -12 hi to 1

PM; 3 to 4; 7:30 to 10:30; 12 to 1 AM.WWI, Detroit, Mich., 352.7 (EST) -8 AM to 8:30;

9:30 to 10:30; 11:55 to 1:30 PM; 3 to 4; 6 to 10.RDKA, Pittsburgh, Pa., 309 (EST) -6 AM to 7;

9:45 en 12:15 PM; 2:30 to 3:20; 5:30 to 10.KWSC, State College of Wash., 348.6 (PST) -7:30

PM to 9.KFI, Los Angeles, Cal., 467 (PST) -5 PM to 11.KFICX, Hastings, Neb., 288.3 (CST) -12:30 PM

to 1:30; 5:15 to 6:15; 9:30 to 12:30.KFNF, Shenandoah, Iowa, 266 (CST) -12:15 PM

to 1:15; 3 to 4; 6:30 to 10.KFOA, Seattle, Wash., 455 (PST) -12:45 PM to

1:30; 4 to 5:15; 6 to 10.KGO, Oakland, Cal., 361.2 (PST) -9 AM to 10:30;

11:30 AM to 1 PM; 1:30 to 6; 6:45 to 7; 8 to IAM.

KGW, Portland, Oregon, 491.5 (PST) -11:30 AMto 1:30; 5 to 8.

KHJ. Los Angeles, Cal., 405.2 (PST) -7 AM to7:15; 12 M to 1:30 PM; 5:30 to 10.

RJR, Seattle, Wash., 384.4 (PST) -1 PM to 2:45;6 to 6:30; 7 to 11.

KNX, Hollywood, Cal., 337 (PST) -12 M to 1 PM;4 to 5; 6:30 to 12.

ROB. State College of New Mexico, 348.6 (MST)-11:55 AM to 12:30 PM; 7:30 to 8:30; 9:55 to10:10.

ROIL, Council Bluffs, Iowa, 2713 (CST) -7:30 PMto 10.KPO, San Francisco, Cal., 425 (PST) -10:30 AM

to 12 M; 1 PM to 2; 2:30 to 3:30; 4:30 to 10.KSD, St. Louie, Me., 545.1 (CST) -7:30 PM is 10.

KTHS, Hot Springs, Ark., 374.8 (CST) -12:30 PMto 1; 8:30 to 10.

KY W, Chicago, Ill., 536 (CSTDS)-6:30 AM to7:30; 10:55 to 1 PM; 2:15 to 3:30; 6:02 to 7.

TUESDAY, OCTOBER 27WAAM, Newark, N. J., 263 (EST) -11 AM to

12 M; 7 PM to 11.WANG, Richmond Hill, N. Y., 316 (EST) -12

PM to 1:05 AM.WAMB, Minneapolis, Minn., 243.8 (CSTI-12 M

to 1 PM, 10 to 12.WBBM, Chicago, Ill., 226 (CST) -8 PM to 12.WBOQ, Richmond Hill, N. Y., 236 (EST) -3:30

PM to 6:30.WBZ, Springfield, Mass., 333.1 (EST) -6 PM

to 11.WCAE, Pittsburgh, Pa., 461.3 (EST) -12:30

PM to 1:30; 4:30 to 5:30; 6:30 to 11.WCCO, St. Paul and Minneapolis, Minn., 416.4

(CST) -9:30 AM to 12 M; 1:30 PM to 4; 5:30to 10:

WDAF, Kansas City, Mo., 365.6 (CST) -3:30PM to 7; 11:45 to 1 AM.

WEAF, New York City, 492 (EST) -6:45 AMto 7:45; 11 to 12 M; 4 PM to 5; 6 to 12.

W R Cleveland, 0., 390 (EST) -11:30 AM toIFA) 'PM; 7 to 10; 10 to 11.

WEE,, Boston, Mass., 476 (EST) -6:45 AM to8; 1 PM to 2; 6:30 to 10.

WFAA, Dallas, Texas, 457.9 (CST) -10:30 AM to11:30; 12:30 15M to 1; 2:30 to 6; 6:45 to 7; 8:30to 9:30; 11 to 12.

WFBH, New York City, 272.6 (EST) -2 PMto 6:30; 11:30 to 12:30 AM.


WGCP, New York City, 252 (EST) -2:30 PMto 5:15.

WGES, Chicago, Ill., 250 (CST) -7 PM to 9; 11to 1 AM.

WGN, Chicago, Ill., 370 (CST) -9:31 AM to 3:30PM; 5:30 to 11:30.

WGR, Buffalo, N. Y., 319 (EST) -11 AM to12:45 PM; 7:30 to 11.

WGY, Schenectady, N. Y., 379.5 (EST) -11 PMto 2:30; 5:30 to 7:30; 9:15 to 11:30.

WHAD, Milwaukee, Wis., 275 (CST) -11 AM to12:15 PM; 4 to 5; 6 to 7:30.

WHAS, Louisville, Ky., 399.8 ((ST) -4 PM to 5;7:30 to 9.

WHAR, Atlantic City N. J., 275 (EST) -2 PMto 3; 7:30 to 9; 11:15 to 12.

WHN, New York City, 360 (EST) -12:30 PMto 1; 2:15 to 3:15; 4 to 5:30; 7:30 to 10:45; 11:30to 12:30 AM.

WHO, Des Moines, Iowa, 526 (CST) -12:15 PMto 1:30; 7:30 to 9; 11:30 to 12.

WHT, Chicago, M 400 (CST) -11 AM to 2PM; 7 to 8:30; 10:3d to 1 AM.

WIP, Philadelphia, Pa., 508.2 (EST) -7 AM to8; 1 PM to 2, 3 to 4:30; 6 to 11.


WJZ, New York City, 455 (EST) -10 AM to11; 1 PM to 2; 4 to 6; 7 to 11.

WRAC, Cincinnati, 0., 326 (EST16 PM to 12.WLIT, Philadelphia, Pa., 395 (EST) -11 AM to

12:30 PM; 2 to 3; 4:30 to 7.WLW, Cincinnati, 0., 422.3 (EST) -10:45 AM to

1 PM; 1:30 to 2:30; 3 to 5; 6 to 11.WMCA, New York City, 341 (EST) -11 AM to

12 M; 6:30 PM to 12.WNYC, New York City, 526 (EST) -3:45 PM

to 5; 6:50 to 11.WOAW Omaha, Neb., 526 (CST) -12:30 PM to

1:30; 5:45 to 11.WOC, Davenport, Iowa, 484 (CST) -12:57 PM to

2: 3 to 3:30; 5:45 to 10.WOO, Philadelphia, Pa., 5082 (EST) -I1 AM

to 1 PM; 4:40 to 5; 10:55 to 11:02.WOR, Newark, N. J., 405 (EST) -6:45 AM to

7:45; 2:30 PM to 4; 6:15 to 7:30.WPG, Atlantic City, N. J., 299.8 (115ST)-7 PMto 11.WQJ, Chicago, Ill., 448 (CST) -11 AM to 12 M;

3 PM to 4, 7 to 8; 10 to 2 AM.WRC, Washington, D. C., 469 (EST) -9 AM to

10; 12 M to 2; 6:55 PM to 11.WREO, Lansing, Michigan, 285.5 (EST) -8:15 PM

to 11.WRNY, New York City, 258.2 (EST) -11:59AM to 2 PM; 4:30 to 5; 8 to 11.WSB, Atlanta, Ga., 428.3 (CST) -12 M to 1 PM:

2:30 to 3:30; 5 to 6; 8 to 9; 10:45 to 12.WSBF, St. Louis, Mo., 273 (CST) -12 M to 1 PM;

3 to 4, 8 to 10, 11:30 to 1 AM.WWI, Detroit, Mich., 352.7 (EST) -8 AM to 8:30;

9:30 to 10:30; 11:55 to 1:30 PM; 3 to 4; 6 to 10.KDKA, Pittsburgh, Pa., 309 (EST) -9:45 PM to

12 M; 1:30 PM to 3:20; 5:30 to 10:45.KFI Loa Angeles, Cal., 467 (PST) -5 PM to ILKFILX, Hastings, Neb., 288.3 (CST) -12:30 PM

to 1:30; 5:15 to 6:15; 9:30 to 12:30.KPMQ, Fayettville, Ark., 299.8 ((ST) -9 PM to

10.KFOA, Seattle. Wash., 455 (PST) -12:30 PM to

1:30; 4 to 5:15; 6 to 11.KGO, Oakland, Cal., 361.2 (PST) -11:30 AM to

1PM; 1:30 to 3; 4 to 6:45; 8 to 1 AM.KGW, Portland, Oregon, 49L5 (PST) -11:30 AM

to 1:30 PM; 5 to 11.KHJ, Los Angeles Cal., 405.2 (PST) -7 AM to

7:15; 12 M to 3:20 PM; 5:30 to 11.RJR. Seattle, Wash., 384.4 (PST) -9 AM to 6:30PM; 8:30 to I AMKNX. Hollywood, Cal., 337 (PST) -9 AM to 10;

1 PM to 2; 4 to 5; 6:30 to 12.

WEDNESDAY, OCTOBER 28WAAM, Newark, N. 7., 263 (EST) -12:30 PM to1:05; 7:30 to 11:05.WAHG, Richmond Hill, N. Y., 316 (EST) -12M to 1:05 PM; 8 to 12.

WAMB, Minneapolis, Minn., 34.3.6 (CST) -12 It1 PM; 10 to la.

WBBM, Chicago, Ill. 226 (CST) -8 PM to 10.WBZ, Springneld, Mass., 333.1 (EST) -6 PM

to 11.WCAE, Pittsburgh, Pa., 461.3 (EST) -12:30

PM to 1:30; 4:30 to 5:30, 6:30 to 11.WCCO St. Paul and Minneapolis, Minn., 416.4

(LST)-9:30 AM to 12 M; 1:30 to 4; 5:30 to 11.W DA F, Kansas City, Mo., 365.6 (CST) -3:30

PM to 7; 8 to 9:15; 11:45 to 1 AM.WEAF, New York City, 492 (EST) -6:45 AM

to 7:45; 11 to 12 111; 4 PM to 5; 6 to 12.WEAO, Ohio State University, 293.9 (EST) -8

PM to 10.WEAR, Cleveland, 0., 390 (EST) -11:30 AM to

12:10 PM; 3:30 to 4:10; 6:45 to 7:45.WEEI, Boston, Mass., 476 (EST) -6:45 AM to

8, 3 PM to 4; 5:30 to 10.WEMC, Berrien Spring, Mich., 266 (CST) -8:I5

PM to II.WFAA, Dallas Texas, 475.9 (CST) -10:30 AM to

11:30; 12:30 PM to 1.WFBH, New York City, 270.6 (EST) -2 PM to

7:30; 12 M to 1 AM.WGCP, New York City, 252 (EST) -2:30 PM

to 5:18; 8 to 10.WGES, Chicago, Ill., 250 (CST) -7 PM to 9; 11

to 1 AM.WGBS, New York City, 316 (EST) -10 AM to

11 PM; 1:30 to 4; 6 to 7.WGN, Chicago, M., 370 (CST) --9:31 AM to 3:30

PM; 5:30 to 11:30.WGR, Buffalo, N. Y., 319 (EST) -12 M to 12:45

PM; 2:30 to 4:30; 6:30 to 11.WGY, Schenectady, N. Y., 379.5 (CST) -5:30 PM

to 7:30.WHAD, Milwaukee, Wis., 275 (CST) -I1 AM to

12:15 PM; 4 to 5; 6 to 7:30; 8 to 10; 11:30 to12:30 AM.


WHN, New York City, 368 EST) -2:15 PMto 5:30; 7:30 to 11; A:30 to 12:30 AM.

WHO, Des Moines, Iowa, 526 (CST) -12:15 PMto 1:30; 6:30 to 12 M.

WHT, Chicago, 111. 400 (CST) -11 AM to 2PM; 7 to 8:30; 10:34 to 1 AM.

WIP, Philadelphia, Pa., 568 EST) -7 AM to8, 10:20 to 11. I PM to 2; 3 to 4; 6 to 8.

WJZ, New York at y, 455 (EST) -10 AM to11; 1 PM to 2; 4 to 6; 6 to 11:30.

WKRC, Oncinnati., Ohio, 326 (EST) -8 PM to 10.WLIT, Philadelphia, Pa., 395 (EST) -12:02 PM to

12:30; 2 to 3; 4:30 to 6; 7:30 to 9.WLW, Cincinnati, 0., 422.3 (EST) -10:45 AM to

12:15 PM; 1:30 to 2:30; 3 to 5, 6 to 11.WMCA, New York City, 341 (EST) -10:45 AM to

12 hi; 6:30 PM to 12.WNYC. New York City, 526 (EST) -6:30 PM

to 11.

WOC, Davenport, Iowa, 484 (CST) -12:57 PM to2, 3 to 3:30; 4

W011, Newark, N. 7., 405 (EST) -6:45 AM to7:45, 2:30 PM to 4; 6:15 to 12 M.

WPAK. Fargo, N. D., 283 (CST) -7:30 PM to 9.WOJ,Chicago, Ill., 448 (CST) -l1 AM to 12 M;3 PM to ; 7 to 8; 10 to 2 AMWRC, Washington, D. C., 469 (EST) -9 AM to

10; 12M to 2; 6:25 PM to 7.WREO, Lansing, Michigan, 285.5 (EST) -10 PMto II.WRNY, New York City, 258.5 (EST) -11:59 AM

to 2 PM; 7:59 to 9:55.WSB, Atlanta, Ga., 428.3 (CST) -12 M to 1 PM;

2:30 to 3:30; 5 to 6; 10:45 to 12.WSBF, St. Louis, Mo., 273 (CST) -12 M to 1 PM:

3 to 4; 7:30 to 9.WVV.I. Detroit, Mich., 352.7 (EST) -6 AM to 8:30;

9:30 to 10:30; 11:55 to 1:30 PM; 3 to 4; 6 to 7;8 to 10.

KDKA, Pittsburgh, Pa.. 309 (EST) -6 AM to 7i9:45 to 12:15 PM; 2:30 to 3:20; 5:30 to 11.

KFAE, State College of Wash., 348.6 (PST) -7:30PM to 9.

KFI, Los Angeles, Cal., 467 (PST) -5 PM to II.KFRX, Hastings, Neb.. 288.3 (CST) -12:30 PM to

1:30; 5:15 to 6:15; 9:30 to 12:30 AM.KFMQ, Fayettville, Ark.. 299.8 (CST) -7:30 PMto 9.KFNF, Shenandoah, Iowa. 266 (CST) -12:15 PM to

1:15; 3 to 4; 6:30 to 10.KFOA, Seattle. Wash.. 455 (PST) -12:30 PM to

1:30; 4 to 5:15; 6 to 10.RGO, Oakland, Cal., 361.2 (PST) -11:30 AM to 1PM; 1:30 to 2:30; 3 to 6:45.KGW, Portland, Oregon, 491.5 (PST) -11:30 AM

to 1:30 PM; 5 to 10KHJ, Los Angeles, CaL, 405.2 (PST) -7 AM to

715; 12 M to 1:30 PM; 5:30 to 12.RJR, Seattle, Wash . 484.4 (PST) -9 AM to 1 AMK7NXto, 1Haollywood, Cal., 337 (PST) -1 PM to 2:

KOIL, Council Bluffs, Iowa. 278 (CST) -7:30 PMto 9; 11 to 12 MRP°, San Francisco. Cal., 429 (PST) -7 AM to

7:45; 10 to 12 M; 1 PM to 2; 3:30 to 11.(CST), St. Louis, Mo., 541.1 (CST) -6 PM to 7.KTHS, Hot Springs. Ark.. 374.8 (CST) -12:30 PM

to I; 8:30 to 10:30.KYW, Chicago. 536 (CST) -6:30 AM to

7-30; 10:30 to 1 PM; 2:15 to 4; 6:02 to 11:30.CNRA. Moncton. New Brunswick, Canada, 313(EST) -9:30 PM to 11.(-NR11, Regina, Saskatchewan, Canada -8 PMto 11.CNRO, Ottawa, Ontario, Canada, 435 (EST) -7

PM to 11

THURSDAY, OCTOBER 29WAAM, Newark. N. J., 263 (EST) -11 AM to12M: 7 PM to 11WANG, Richmond Hill N. Y., 316 (EST) -12:38

PM to 16$(Concluded on page 23)

20 RADIO WORLD October 24, 1925A THOUGHT FOR THE WEEK

Apparent impossibilities in radio todayoften become accomplished facts tomor-row. Research is better than theory.

ran,11.Disanbutee sod II....Dant

Rad:le World's Slogan: "A radio sot for every home."

TILIPHONES: BRYANT 0558, 0559PUBLISHLD STREIT WWDNIIISDAT

(Dated Saturday of same week)PROM PUBLICATION MICA

iliNNISBY RADIO PUBLICATIONS CORPORATIONROLAND BURRS EllifiNRSST, President

M. B. EIBMNISST, Ties -ResidentMIND S. CLARK, Secretary and Manager

145 NOT 45th STREIT, NNW TORS, N. T.(Between Broadway and Sixth Art.)

Raregea ReprimandIves: The International New. On.Breams Ridge.. Chummy Lane, London. W.

Path, Wrath Brentirse's. II Avenue tie l'Opera.adaago Representatives. A. T. Sears & 8011, Peeples Oa.

Bldg.Cincinnati Office: Radio World, 904 Provident Bk. Bldg..

7th and Vine Ste. Telephone, Canal 755 and 879.San Prancisoo, Lloyd B. Chappell, 658 O'Perrell St.

Em1241111.

SUBSCRIPTION RATESriftees ante sew. $6.85 year. 19.15 for sic

months. $1.511 for three months. Add $1.118 yearextra for foreign postage. Canada, 66 mats.

Rthipt by new subsrtibere of the first spy of RADIOWORLD mailed to them after sending in their order laautomat% acknowledgment of their subscription order.Chimes of address should be received at this offlaso twoweeks before date of publication. Always give old addressalso. State whether subeeription is new or removal.

ADVERTISING RATESGeneral Advertising

1 Page, 744":11" 461 lines 1515.50% Page, 744":115" 551 lines 150.00% Page. 4/6" D. 0. 115 lines /5.001 Column, 244":11" 154 lines 100 et1 Inch 1 . et

Per Agate line .75Times Mumma

51 cosseentive berm 80%10 Wass eonsesutively or 1. O. W. ens yea 15%4 enwoutics issues le%WICIIN-LT, dated each Saturday, published Wednesday.

Advertising forma *lose Turellay, eleven days in advanceof date at Isies.

CLASSIFIED ADVERTISEMENTSTess ants per wad. Minimum. 10 wads. Caen with

order. Badness Opportuzities 50 sent' line; mini-mum. $1.011.

Inured se seeond-ewe matter. Marsh 12, 1921. asthe Pest Offin at New York, N. T., wader the est elMarsh 5, 1819.

OCTOBER 24, 1925

Pure Thorium MadePractical for Tubesto Replace Mixture

The Westinghouse Lamp Company, 150Broadway, New York City, announcedthat after long investigation its researchlaboratories had added a new metal to theworld's technical resources in the form ofpure metallic ductile thorium. The state-ment was issued by Dr. H. C. Rentschler,head of the company's research depart-ment, and Dr. J. W. Marden.

Thorium, it was said, was of particularinterest to the radio enthusiasts becauseit was the active constituent of practicallyall radio tube filaments. It can now beproduced commercially in filamentaryform as contrasted with the minute ad-mixture with tungsten now used. In addi-tion to its use in radio tubes, this metalis said to be of great importance to themedical profession as a target materialfor X-ray tubes, being more efficient thanthe tungsten now in use.

The Mission ofA MunicipalRadio Station

What's going to happen when everyenterprising community puts up a broad-casting station to invite a travel -hungryworld to come and bask in the glow ofthe rainbow's end, sample the pot of goldand bathe in the fountain of youth?

That question probably has occurred tomost of us who have watched and listenedthrough the period of experimentationwith radio as a medium for communityadvertising.

What about the answer?The Invitation

The question will never have to beanswered because that condition of affairsnever will quite come to pass. We mayget pretty close to it before the full lessonis learned, but long before the time whenthe perspective pleasure -seeker, thewould-be home -seeker, and the yearninghealth -seeker would be carted off kickingand screaming to the nearest asylum, thecommunity radio broadcasting outfits willhave awakened to a true appreciation oftheir earlier indiscretions.

Then, instead of being puzzled andbored and harassed about where lies ourfuture health and happiness, profit andpleasure, we'll begin to be really enter-tained, amused and informed through themedium of the municipal radio broadcast-ing station.

When it comes to advertising, radio isbeing employed with skill and science.Programs entertain, amuse and informpeople-tell them what they want to know,present to them sounds and sights andsensations that are pleasant. Radio isproperly used as a good -will builder ratherthan a direct sales medium.

The Case of JacksonvilleThe school of municipal radio broadcast-

ing is beginning also to learn this valuablelesson. Witness, for'instance, the caseof Jacksonville, Florida. Here is a citythat is erecting a broadcasting station asa project of the city government to en-tertain, amuse and educate its own peopleand those within hearing of the station.

Of course Jacksonville expects thisradio station to help advertise Jackson-ville. As a matter of fact it expects thestation to play a very substantial part inthe program of telling the world things itwill be pleased to know about Jackson-ville and her opportunities and advantagesas a port, an industrial center, a distribut-ing point in one of the most rapidly grow-ing consuming centers of the country, thecenter of a famous agricultural territoryand a resort city of unusual advantagesand facilities.

But the methods by which the municipalradio broadcasting station will accomplishits part of the program of advertisingJacksonville to the outside world, will bethe most intproved, the most up-to-datemethods. It will be painless. Nay, more,it will be really pleasurable. For Jackson-ville is determined that her municipalbroadcasting venture shall reap for hera harvest of friends, visitors, and newcitizens.

Civic Music PlannedA municipal orchestra, now being

formed with the best local talent andtrained by really high class musicians andinstructors, will be the nucleus for themusical treats that will be part of dailyprograms to be broadcast from Jackson-ville. These musical offerings will beamong the best to be heard in thecountry.

If Jacksonville has a story to tell overher radio broadcasting station, she willmake certain before the telling that it isa story which is interesting andinstructive

Coolidge Broadcasts

PRESIDENT COOLIDGE addressingmembers of the American Legion at theNational Convention at Omaha, Neb.This speech was broadcast. Note themicrophone at the right near Com-mander Drain of the American Legion.

Even the DyingHeard Schipa

and JournetThe greatest volume of mail ever re-

ceived at KGO from a single broadcastpoured into the station as a result of therecent concert of Victor Artists, duringwhich Tito Schipa and Marcel Journet,grand opera singers, and an orchestraselected from the personnel of the SanFrancisco Symphony, under the directionof Joseph Pasternack, gave an hour ofmusic.

Before the concert was over telegramsfrom all over the United States, Canada,Alaska, Hawaii and Mexico were re-ceived. Letters at the rate of severalhundred daily followed.

A Variegated AudienceNever before in western musical history

did so diverse a crowd listen to grandopera music as is shown in the mail. Thou-sands of sick, many of them for the lasttime, heard the golden voice of Schipa.Miners in the high Sierras, with their feetcomfortably placed on ramshackle stoves,ranchers in the valleys, men, women andchildren of San Francisco Chinatown, andin five other great western centers ofChinese population; all listened to theepochal broadcast. Campers, forest rang-ers, lighthouse keepers, firemen in theboiler rooms of trans -Pacific liners, can-nibals in islands of the South Seas,Eskimos in Alaska, all heard; and manyare doing their best to applaud by mailnow received daily.

Theatre CrowdedThe San Francisco Municipal auditorium

seating almost 7,000 people, was packed,and it is estimated that 3,000 were turnedaway, from the concert arranged to beheard over giant power radio loud speak-ers, the tone from two of which filled themonster building and brought forth stormsof applause. The audience, seated in thedarkness listening, and seeing nothing,was nevertheless conscious of the greatheart of the artist, Schipa, when he sang"0 Solo Mio," said a prominent San Fran-cisco musician.

Hundreds of music stores, radio shops,garages and private homes up and downthe Pacific Coast were packed with people,listening to the broadcast from speakers.

to the millions of owners of radio receiv-ing sets who will hear it. It must besomething that the people of Jacksonvilleand the outside world really want to hearand will be grateful for having heard.


Radio Entertains Sportsmen

POPULAR sportsmen enjoy listening to the radio, before the golf game, it being playedin an unusual style. That is each man used his own "weapon" and not a golf stick.The people in photo from left to right are: Leo Diegel (champion pro -golfer); LouGehrig (Yankee 1st baseman); Edw. Harkins (boy champion plug and surf caster);E. Blackman (judge and president of club), and Dr. Crouch (American archery cham-pion). Seated front: Ralph Pulitzer and Dr. C. Simon (Deputy N. Y. Police Com-

missioner). (Foto Topics).

Song Publishers' VictoryUpheld by Highest Court

The Supreme Court of the United Statesrefused to review the decision in favor ofJerome H. Remick & Co., New York musicpublishers, against WLW, Cincinnati,wherein the publishers won a victory overthe broadcasting of copyright music. TheSupreme Court's action is tantamount tosustaining the decision of the lower appel-late court.

The stake involved is the payment ofroyalties to the American Society of Com-posers, Authors and Publishers.

The Court of Appeals in Cincinnati hadreversed the ruling of a lower FederalCourt judge who had decided that broad-casting did not constitute a public per-formance and that, therefore, stations en-gaged in sending out music did not violatethe copyright laws. The reversal by thefirst appellate court confirmed previous de-cisions won in the East by the society,which was able to prevent Bamberger &Co. in Newark and the General ElectricCompany from broadcasting without roy-alty payments.

The Court of Appeals, however, stayedits mandate against the Crosley corpora-tion pending application to the UnitedState Supreme Court, whose action willterminate the stay.

The society, as a result of a conferenceheld last Summer and attended by Rep-resentative Sol Bloom, chairman of theHouse Committee on Patents, will presenta new copyright bill at the next sessionof Congress which convenes in December.The Radio Manufacturers' Association, atits last convention, appointed a commit-tee to attempt to iron out differences be-tween the two groups over the proposedlegislation.

The radio men may possibly effect somecompromise with the society before Con-gress meets, but all other mechanical re-production companies, with the exceptionof the Victor Talking Machine Co., have

served notice that they intend to fight thebill.

The society, in the legislation it proposes,goes much farther than the mere insis-tence of payment for use, a right whichwas established by the Supreme Court'sruling. They now insist upon the com-poser's and author's right to bargain in-dividually with all reproducing organiza-tions.

Under the present copyright law a com-poser who has bargained with and soldto one reproducing company is then re-quired to sell to all others at a certainfixed rate.

McCormack Eager to SingFor Radio Again-at Price

The much -repeated rumor that JohnMcCormack, the tenor, would sing nomore before the microphone was deniedby him on his recent return from Europe.He is ready, willing and even eager tosing-for a price. "I am a business man,"he said.

As he stepped off the gangplank of theMauretania he told a RADIO WORLDreporter:

"I'm a business man. I never said thatI would not sing over the radio. I willsing when they come to me with a busi-ness proposition."

Regarding the Atwater -Kent series ofSunday night operatic concerts fromWEAF and allied stations, where evenartists under contract with the Victor andBrunswick companies broadcast, as well asMetropolitan Opera House singers, hesaid:

"That's a step in the right direction."McCormack said he was so delighted

with the experience of singing in the firstoperatic concert broadcast last New Year'snight over WEAF in conjunction with

Steinway Swells

Ranks of GreatRadio Concerts

Three great artistic broadcasting fea-tures are to run through the better partof the winter. Besides the Atwater -Kenthour every Sunday night from WEAFand allied stations, and the promisedoperatic and concert programs from WJZ,WGY and WRC, there will be a seriesthrough WJZ, etc., by Steinway & Sons.Josef Hofmann, pianist; Walter Dam-rosch, conductor, Mme. Ernestine Schu-mann-Heink, contralto, and WillemMengelberg, conductor, will be heard. OnOctober 27 (Tuesday). On that occasionMengelberg, guestconductor of thePhilharmonicOrchestra, will con --duct the program.Hofmann will give arecital. A specialfestival hymn, com-posed by Mr. Men-gelberg for orchestraand bariton; solo,will be rends red forthe first t:me inAmerica. FraserGange will be thesoloist.

Sunday night, Nov.8, Walter Damroschwill be the pianist -conductor in a per-formance of the"Kreutzer Sonata"for piano and violin.Paul Kochanski will

Friday, December4, Madame Schu-mann-Heink will befeatured in a song re-cital.

In addition therewill be interspersedduring this periodother concerts andrecitals to be broad-cast.

On Sunday night, October 11, ToschaSeidel, violinist, was the feature of theKent program at WEAF.

TOSCHA SEIDEL

the Victor Company that he would beglad to sing again to a radio audience.

McCormack suggested that Americanbroadcasting companies follow the Britishin obtaining revenue with which to paythe artists. He said that a tax was placedon every receiving set to raise the fundfor talent broadcast. In that way theradio audience was asked to pay for itsentertainment.

He remarked he was 50 and had no in-tention of retiring until he was 60.

Broadcaster SendsS 0 S for a Change

WASHINGTON.Generally when S. 0. S. calls (signals of

distress) are heard on the air, they comefrom ships at sea and broadcasting sta-tions are required to keep silent. The sit-uation was reversed one night recentlywhen an S. 0. S. call was sent out byWGBU, Fulford, Fla.

Fire of unknown origin broke out andthe Alabama Hotel at Fulford was de-stroyed by fire. The only telephone inFulford was enveloped in flames. A mes-senger rushed word to WGBU where An-nouncer Harold McCray sent out four ap-peals to radio fans to phone the fire de-partment in Miami.


THE RADIO TRADE Literature Wanted

Colin B. Kennedy Headsthe Voice of St. Louis

ST. LOUIS.Cohn B. Kennedy, president of the Colin

B. Kennedy Corporation, was elected pres-ident of the Voice of S . Louis, Inc., at ameeting of thestockholders of thatorganization, whichhas been formed todevelop the newcommunity radio -casting project. E.Lansing Ray, presi-dent of the "Globe -Democrat," waselected chairman ofthe Board of Direct-ors, comprising Mr.Kennedy, CliffordCorneli, manager ofthe Schisler - CornelSeed Company and representative of theMerchants Exchange; Spyros P. Skouras,president of Skouras Bros.' enterprises,and A. G. White, advertising manager ofthe Brown Shoe Company. Thomas P.Convey was named managing director.

Kennedy, who was one of the originalorganizers of the new broadcasting pro-ject, has been identified with the radioindustry for several yers, not only as amanufacturer but also through his affilia-tion with national radio bodies. He ispresident of the St. Louis Radio TradesAssociation.

Corneli, as chairman of the specialRadio Committee of the Merchants' Ex-change of St. Louii, has been active inidentifying that organization with TheVoice of St. Louis project, in which theplan of broadcasting market reports hasbeen one of the prime considerations.

Skouras represents the Skouras Bros.'enterprises and the permanent studio ofthe new project will be located in the NewAmbassador Theatre Building when thatstructure is completed next year. Thetemporary studio will be located in theMayfair Hotel.

White has been active in advertisingwork and civic affairs in St. Louis forseveral years.

Convey, who is general manager of theSt. Louis Radio Trades Association, hasbeen in charge of the development of theVoice of St. Louis organization, withoffices at 737 Frisco Building.

COLIN B.KENNEDY

Powerola a Batteryless5 -Tube Receiver

Powerola is electric radio without anybatteries or chemicals whatever. It canbe used universally, operating directlyfrom the standard AC or DC lightingcircuits in the home, office or place ofbusiness. By plugging into the houselighting socket, the tubes in the receiverare lit and the set is ready for tuning. Itbecomes another electric necessity likean electric iron, toaster, or other electricaldevice.

For alternating current, two rectify-ing bulbs (2 ampere), in connection witha transformer, condensers and choke inthese circuits, enables the receiver toobliterate all power -line hums and noises,and to deliver the required voltages andwatt power. For direct current a simplebut practical arrangement is employedin connection with a choke, some con-densers and resistances, and with thefilaments of the tubes in series, which also

noises, and produces the needed constantsand potentials.

There are no additional controls addedon the rectifier or set to compensate avariation in voltage on the 110 -volt sup-ply, AC or DC. Powerola is designed forAC 100-115 volts, 40-60 cycles, and for

,DC 110-1120 volts.Five standard tubes, such as the five

or six volt 201A or 301A, and standardphones and loud speakers are employed.

The Terminal Electric Company is themanufacturer.

A Free BookletThe Amsco Products, Inc., Broome and

Lafayette Sts., N. Y. City, offer free toRADIO WORLD readers their bookletentitled "The Heart of the Hooking," dis-cussing designs of great interest to radioexperimenters.

Every article is discussed thoroughly,both electrically and mechanically. Thesediscussions are presented in an interestingand simple manner and any novice canfully understand all that is printed.

MOHAWKS NOW DISTINGUISHEDTo avoid any confusion between the

business of Earl B. Rollinson conductednuder the name of Mohawk Electric Mfg.Co., at 15 Kirk Place, Newark, N. J.,and its own business, located at Diverseyat Logan Boulevard, Chicago, the cor-porate name of the Mohawk Electric Corp.(Chicago) has been changed to MohawkCorporation of Illinois.

Coming EventsOCT. 17 to 24-Brooklyn Radio Show, 23d Regt

Armory. Write Jos. O'Malley, 1157 Atlantic Ave.Brooklyn, N. Y.

OCT. 19 to 25-Second Annual Cincinnati RadioExposition. Music Hall. Write to G. B. Boden-hof, care Cincinnati Enquirer.

OCT. 28 to 31-First Annual Rochester Times -Union Radio Exposition, Convention Hall, Roch-ester, N. Y. Write Howard H. Smith, careTimes -Union.

NOV. 2 to 7-Radio Show, Toronto, Can., Cana.dian Expos. Co.

NOV. 3 to 6-Radio Trade Association Exposi-tion, Arena Gardens, Detroit. Write Robt. J.Kirschner, chairman.

NOV. 7 to 14-Second Columbus Radio Showand Electrical Exposition. Write Lewis Hill,Dispatch, Columbus, 0.

NOV. 19 to 25-Milwaukee Radio Exp., CivicAuditorium. Write Sydney Neu, of J. Andrae &Sons. Milwaukee, Wis.

NOV. 17 to 22 -4th Annual Chicago Radio Exp.,Coliseum. Write Herrmann `& Kerr, Cort Theatre,Bldg., Chicago, Ill.

NEW CORPORATIONSRusonite Condenser Corp., N. Y. aty, general

merchandise, 200 common, no par; T. H. Foley,W. W. Hoover, M. E. Sparrow. (Atty., P.Freeman, 1482 Broadway, N. Y. City).Duolone Radio Corp., Wilmington, Del., $150,000.

(The Corp. of Wilmington, Del.).I. H. Greene Hardware Co., N. Y. City., radio,

623,000; L H. Greene and A. L Orbach. (Any's,Benjamin & Sholes, 159 Remsen St., Brooklyn,N. .).

Pine Tree Radio Corp., Brooklyn, N. Y., $10,000;J. Engler, H. H. Jackson, L. Ranks (Atty., P.Jones, 38 Park Row, N. Y. City).

Tillman Radio Products Corp., Del., $300,000;Morris Goldberg, Max Loentahl, Brooklyn; HarrySands, New York. (American Guaranty TrustCa).

Solex Electric Co., N. Y. City, $20,030; A.Konoff, H. H. Reider, S. G. Lipschitz. (Atty., L.A. Jacobs, 805 Broadway, N. Y. City). -

THE names of readers of RADIO WORLDwho desire literature from radio job-

bers .and dealers are published in RADIOWORLD on request of the reader. Theblank below may be used, or a post cardor letter will do instead.Trade Service Editor,RADIO WORLD,145 West 45th St., N. Y. City.

I desire to receive radio literature.Name

City or town

State

Are you a dealer?If not who is your dealer?

His Name

His Address

Ralph Tuttle, 418 -4th St., Clarkson, Wash.(Dealer.)

Ray Turley, Willow Lake, S. D. (Dealer.)Mrs. A. C. Nelson, 804 Dewey St., Boulder, Col.A. E. Mougey, 1001 N. Main St., Sidney, 0.

(Dealer.)Turnell Radio Shop, 4242 Cottage Grove Ave.,

Chicago, El. (Dealer.)0. R. Gorgenson, Bellingham, Wash.Paul Truog, Kintnersville, Pa.A. M. Forster, 992 Jefferson Ave., Buffalo, N. Y.

(Dealer.)J. Reynolds Gunn, Pittsburgh, Tex. (Dealer.)Crescent Studio, Louisville, Ky. (Dealer.)A. J. Smith, Jr., Anson, Tex. (Dealer.)Frank E. Earley, Oklahoma City, Okla. (Dealer.)Allen Whitmore, 340 W. 46th St., Los Angeles,

CaLA. J. Buech-1, Buffalo, N. Y. (Dealer.)Fred Clode, Motor Route A, Millville, N. Y.Gold Seal Radio Co., Cedar Rapids, Ia. (Dealers.)P. Gillispie, 6011 Calumet Ave., Chicago, Ill.G. Dislumback, W. Frankfort,L F. Bolbecker, Erhaut, Pa. (Dealer.)Wells Motor and Radio Supply Co., 429 East

6th St., Tucson, Ariz. (Dealer.)John J. Zimmerman, 405 Davis Ave., Arlington,

N. J.Harry A. Poling, Route 1, Sheffield, Ala.Abery Radio, Hartford, Conn. (Dealer.)Ivan Reaton, Oberlin, Kan.William Hehemann, 1647 Cliff Ave., Cincinnati,

Ohio.W. L Bickford, 116 Appleton St., Boston, Mass.J. C. Dennis, Jr., 1065 Kossuth St., Bridgeport,

Conn.

CLEAR, SIMPLE LANGUAGEDELIGHTS AMESBURY FAN

I have purchased at different times acopy of nearly every radio magazine Ihave seen on the newsstands. The troubleI find with most of them is that aftera fan reads them (if he will) his mind isso muddled he is disgusted with radio.But with RADIO WORLD it is different.The language you use is so simple that itcan be easily understood. I think it isthe best magazine for a fan.

W. J. Mullally,Amesbury, Mass.

Business OpportunitiesRadio a n d Electrical

10 cents a word. $1.00 Minimum.

RADIO PANEL ENGRAVING PLANT for sale;fully equipped; low rent; good location; $2,500required. 237 Greenwich St., N. Y. C.

MACHINE SHOP, fully equipped, in Long IslandCity, with considerable idle machinery, wouldlike to connect with buyer of small metal partsfor filler work at cost. Will pay broker to con-nect. Box 10, RADIO WORLD.

RADIO PARTS manufacturing concern; greatopportunity for man; $5,000; established cus-tomers of the entire United States and Canada;large profits; season starting. Box 100, RADIOWORLD.

RADIOWanted-Partner with $5,000 to join me in

taking over plant fully equipped manufacturingradio sets, transformers, A and B battery elimin-ator and other parts; opportunity lifetime for any

smoothes out all generator hums and Kasindorf, A. G. Sidelle, E. (Attys.,cziat.leg get into radio. Box 200, RADIO

IMP


THE KEY TO THE AIR(Continued from page 19)

WAMB, Minneapolis, Minn., 243.8 (CST) -12 Mto 1 PM; 10 to 12 M.

WBBM, Chicago, III., 226 (CST) -8 PM to 10.WBUQ, Richmond Hill, N. Y., 236 (EST) -3:30

PM to 6:30.WBZ, Springfield, Mass., 333.1 (EST) -6 PM

to 11:45.WCAE, Pittsburgh, Pa., 461.3 (CST) -12:30 PM

to 1:30; 4:30 to 5:30; 6:30 to 11.WCBD, Zion, W., 344.6 (CST) -8 PM to 10.WCCO, St. Paul and Minneapolis, Minn., 416.4.

(CST) -9:30 AM to 12 hi; 1:30 PM to 4; 5:50to 10.

WEAF, New York City, 492 (EST) -6:45 AM

Save 20650ZFREE RADIO CATALOG

Get the lowest rock -bottom price,on radio parts, sets kits. New free

Radio Catalog and Guide 1, imfulstandard, reliable. guaranteed t o dxOver 100 /atest hook-ups and illustra-tions. Be sure to get this thriftyhook before you buy. It puts mane:in your pocket. Saves you asmuch as half on a set. Also pleaseInclude name of radio fan. Sendletter or postal NOW.

TivE_ BARAWIK COMPANY183-140 S. Canal St., Chicago, U. S. A.

A Satisfied Radio DealerThe Seal of

Satisfaction

Gets quantity discounts.quick shipments. guaran-teed products. reliable re-pairs. personal attentionand real SERVICE. Allof these things are rep-resented by THE SEALO F SATISFACTION."Look for ICI It appearson all radio supplies soldby us. It Is your guar-antee of satisfaction.Write us a card today.Just say. I am interestedIn The Peal of Satisfac-tion, or send three two -rent stamps for our newLoose Loaf Catalog.

THE BOWER RADIO SHOPREADING, MICHIGAN

RADIO DE LUXETHE CLEARFIELD 6 TUBE

Encased In piste glass tattiest. Tweed Radio Frequeasy with Resistance Coupled Anion/Ha- eil5the. True Tone Quality. List Prise (7A

Write for Illustrated BookletSherman Radio Mfg. Corporation

112.114 Trinity Piaui New York. N. Y.Dealers write for our proposition.

Get Your CoilConnections Right

When You Build

The

Powertone

2

Construction of this 1 -dial, 5 -tube qualityreceiver fully described and illustrated, with"blue print In black" Included, in Aug. 29and Sept. 5 Issues. Special discussion of howto romance the call terminals. Troulike-ehoot-lag In this set, Sept. 12 Issue. Send 4.5c.Get all three.

RADIO WORLD145 West 45th St., N. Y. City

to '145; 11 to 12 M; 4 PM to 5; 6 to 12WEAR, Cleveland, 0., 390 (EST) -10:30 AM

to 12:10 PM; 3:30 to 4:15; 7 to 11.WEEL Boston, Mass., 467 (EST) -6:45 AM

to 7:45; 1 PM to 2; 2:30 to 10.WFAA, Dallas, Texas, 475.9 (CST) -10:30 AM to

11:30; 12:30 PM to 1; 2:30 to -6; 6:45 to 7; 8:30 to9:30, 11 to 1 AM.

WFBH, New York City, 272.6 (EST) -2 PMto 7:30.


WGCP, New York City, 316 (EST) -2:30 PMto 5:15.

WGES, Chicago, D1., 250 (CST) -5 PM to 8;10:30 to 1 AM

WGN, Chicago, .11L, 370 (CST) -9:31 AM to 3:30PM; 5:30 to 11:30.

WHAD, Milwaukee, Wis., 275 (CST) -11 AM to11:30; 6 PM to 7:15; 8:30 to 11.

WGR, Buffalo, N. Y., 319 (EST) --12 M to 12:45PM; 2 to 4; 7:30 to 11.

WHAD, Milwaukee, Wis., 275 (CST) -11 AM to12:15 PM; 4 to 5; 6 to 7:30; 8 to 10.

WHAR, Atlantic City, N. J., 275 (EST) -2 PMto 3; 7:30 to 10.


WHN, New York City, 360 (EST) --2:15 PMto 5; 7:30 to 11; 11:30 to 12:30 AM.

WHO, Des Moines, Iowa, 526 (CST) -7:30 PM to9.4 2.11 to 1

Chicago, EL, 403 (CST) -11 AM to 2PM;7 to 8:.90; 10:30 to 1 AM.


WJZ, New York City, 455 (EST) -10 AM to11; 1 PM to 2; 4 to 6; 7 to 12 M.

WLIT, Philadelphia, Pa., 395 (EST) -12:02 PMto 12:30; 2 to 3; 4:30 to 6; 8:30 to 9.

WLW, Cincinnati, 0., 422.3 (EST) -10:40 AM to12:15 PM; 1:30 to 5; 6 to 8, 10 to IL

WMAK, Lockport, N. Y., 265.5 (EST) -11 PM to1 AM.

WMCA, New York City, 341 (EST) -11 AM to12 M; 6:30 PM to 12.

WNYC New York City, 526 (EST) -3:1S PMto 4:15; 6:50 to IL

WOAW, Omaha, Neb., 526 (CST) -12:30 PM to1:30; 5:45 to 11.

WOC, Davenport, Iowa, 484 (CST) -12:57 AM to2 PM; 3 to 3:30; 4 to 7:10; 8 to 9.

WOR, Newark, N. j., 405 (EST) -6:45 AM to7:45; 2:30 PM to 4; 6:15 to 7.

WPG, Atlantic City, N. J., 799.8 (EST) -7 PMto 11.

WQJ, Chicago, Ill., 448 (CST) -11 AM to 12 M;3 PM to 4,- 7 to 8; 10 to 2 AM.

WRC, Washington, D. C., 469 (EST) -1 PM to2; 4 to 6:30.

WREO, Lansing, Michigan, 285.5 (EST) -8:15 PMto 9:45; 10 to 11.

to 2 11'M; 7:39 to 10.WSB, Atlanta, Ga., 428.3 (CST) -12 M to 1 PM;

2:30 to 3:30; 5 to 6; 8 to 9; 10:45 to 12.WSBF, St. Louis, Mo., 273 (CST) -12 M to 1 PM;

3 to 4; 8 to 9.WWJ, Detroit, Mich., 352.7 (EST) -8 AM to 8:30;

9:30 to 10:30; 11:55to1:30; 3 to 4; 6 to 7; 8 to 9.KDKA, Pittsburgh, Pa., 309 (EST) -9:45 AM to

12:15 PM; 2:30 to 3:30; 5:30 to 10:15.KFAE, State College of Washington, 348.6 (PST)

-7:30 PM to 9.RFT Los Angeles, Cal., Mg (PST) -5 PM to 11.EFIUC, Hastings, Neb.. 288.3 (CST) -12:30 PM to

1:30; 5:15 to 6:15; 9:30 to 12:30.KFNF, Shenandoah, Iowa, 266 (CST) -12:15 to

1:15 PM; 3 to 4; 6:30 to 10.EGO Oakland, Cal., 361.2 (PST) -11:30 AM to 1

PM; 1:30 to 3; 4 to 6:45; 7:15 to 10.KGW, Portland, Oregon, 491.5 (PST) -11:30 AM

to 1:30 PM; 5 to 11.KEIJ, Los Angeles, Cal., 405.2 (PST) -7 AM to

7:15; 12 M to 3:20; 5:30 to 11:30.KJR, Seattle, Wash., 484.4 (PST) -9 AM to 1 AM.KNX, Hollywood, Cal., 337 (PST) -11 AM to 12:05

PM; 4 to 5; 6 to 12.ROIL', Council Bluffs, Iowa, 278 (CST) -7:30 PM

to 9.KPO, San Francisco, Cal., 429 (PST) -7 AM to 8;

10:30 to 12 M; 1 PM to 2; 3:30 to 11.KSD, St. Louis, Mo., 595.1 (CST) -7:30 PM to 9.CNRA, Calgary, Alberta, Canada, 435.8 (MST) -

9 PM to 11.

DX Work on DiamondPraised by Jerseyite

DIAMOND EDITOR:

Having had the opportunity and like-wise the pleasure of speaking to your Mr.Bernard in person while at the radio showin the Grand Central Palace I mentionedthat I received two Chicago stations onthe loud speaker on his Diamond of theAir.

After I reached home again I tried totune in those Chicago stations, and to my

1925 BACK NUMBERS OF RADIO WORLD WANTEDMail us copies of any of the following 1925 issues of RADIO WORLD, and wewill send you a copy of a current issue for every copy sent us: January 10,February 7, March 21, 28; April 4, 11; May 30.

surprise ill spite of the terrible staticthey came in on the loud speaker again.

I then tried for more stations, and justthink, besides the two stations WBBMand WOK, mentioned before, I succeededin getting also WENR, WEBH and WIBOon the speaker.

There was also a station whose callletters I could not get right on accountof the static (it sounded to me like WHBor something similar), also Chicago, whichhas a wavelength a little less than WOK,and which at times was very loud andthen faded away.

PHILIP WELLHAUSEN,346 Livingston St.,

Elizabeth, N. J.

((/.°V L.TTLL, OwIF YOUR INVENTION is new and useful it Ispateatable. Send me your sketoh. Z. H.POLACHEK. 7n Well St., New York.

Reg. Patent AttorneyEngineet

The KELLOGGSYMPHONY REPRODUCER

All that the name implies In beauty of lone, volumeand aepsaranee. Priced at $25.00. and worth farmore when the marrelous quality at the reception iscompared with that of ordinary "loud speakers."Ask your dealer for a demonstration. or If yourdealer does not carry it, write for folder R.W.

KELLOGG SWITCHBOARD & SUPPLY CO.1066 W. Adams 3t. Chicago. 111.

DEALERSWrite us for the name of the jobber

who will sell you

Double Toroid CoilsNO -NOISE VARIABLE GRID LEAK

RADIO FOUNDATION, INC.25 W. Broadway New York, N. Y.

LOUD SPEAKER RECEPTIONfrom either coast on three tubes.

Blueprint and h.tructiona MOONecessary low loss coil $2.50Beautiful finished instrument $35.00

S. A. TWITCHELL CO.1930 Western Avenue Minneapolis, Minn.

Veby Resistors and Grid LeaksRadio Engineers and Experimenters find that theVERY PRODUCTS give greater eatisfaction. TheHome Set Builder will he wise to Profit by theexperience of the learned insist on VERY reestorsand grid leaks -accept no substitute.

"Quake], Resistors"VEBY RADIO COMPANY

47.51 Morris Avenue Newark, N. J.

S.M. AGE N TeS140_ MAI WANTED

S'Rabe Demonstrator FREE!Earn $25 to $100 a week. part or full time. Everyonea prospect. Complete line standard sets and accesorles,$5 to $90. Write today for illustrated catalog andexclusive selling plan for live dealers and community agents.20T11 CENTURY RADIO CO., 1101 Coca Cola Bldg..Kansas City. Mo.

-G-R-49-SZ-kElYRADIO CATALOG FREE

oc,cribes fully the complete line of radio frequencysets. regenerative sets (licensed under ArmstrongU. B. Patent No. 1.113.1491 and parts.Write Catalog Today.THE CROSLEYfor RADIO CORPORATION

POWEL C RO SL EY. Jr., President7100 S.i- ,fr.. t-tr- t Cincinnati, Ohio

S. HAMMER RADIO CO.303 Atkins Avenue, Brooklyn, N. Y.

Please send ma FREE, Your NEWRADIO CATALOG

NameAddressCity State

FILL OUT AND MAIL


Fixed Condenser MistakesPointed Out by Andersen

(Continued front page 11)But this is done without regard for quality.The reason a by-pass condenser connectedacross an audio -frequency device shouldnot be any larger than absolutely neces-sary is that it not only by-passes the highfrequency it is intended to do, but alsothe higher frequencies in the audio signal.

5 in 1 ConnectorUse I to 5 limeade ea amr NOWS et with P N Binelg Peels.AA year Dealer, as II*. Par.Peetpaid.

JOBBERS. DEALERSPRICES ON REQUEST

SNOW & COMPANYD ept. W. 145 Mini St.. Nov Vert

This introduces distortion, and if the con-denser is too large the distortion becomesserious. The effect is a general loweringof the tone of the signal, and particularlyit makes it difficult to distinguish betweensuch sounds as s, z, v, f, and other sibilantsand fricatives in the sound as reproducedin the speaker. It does not matter wherein the circuit a condenser is, so long as

Long Distance Radio$2.95

Lambert's newest crystal suttees. Nstubes. No batteries. No grief. Al.ways ready. Works 600 miles. Fullyguaranteed. We Pea Postase. Orderdirect from this ad. Lean Lambert.Wichita, Kansas.

An Imposing ProductAt a Modest Price !

By manufacturing 3,000 a day we are able to sellStreamline Straight -Line Frequency Condensers directto the public at an astonishingly modest price for sucha splendid low -loss instrument.

.0005(23 plates)

.00035(17 plates)

.00025(11 plates)

$2.50

$2.25

$2.00

STREAMLINE RADIO CO.,Dept. WI, 721 Fulton Street, N. Y. Qty

Enclosed find $ for which send me byreturn mail Streamline SLF condensers,capacity

NAME

ADDRESS

CITY STATE

grworrrsir vwfir. Irwin dna%01 illittiv1141111 is iitiiJAV kk!.223 FULTON STREET

(NewYork city

it is across an audio -frequency device theeffect will be the same, and it is cumu-lative. The more by-pass condensers thegreater will be the effect. A practicalresult of this distortion is that one oftenfails to understand a speaker without agreat deal of straining. It may not affectmusic to the same extent because thosefrequencies lie above the fundamentalfrequencies of even the highest pitchedsounds occurring in music, yet it doesaffect the overtones and hence the timbreof the music.

A Double PurposeFixed condensers across batteries, if

used at all, should be as large as prac-ticable. The greater their capacity thebetter they perform their work. Theyare used for two purposes1 namely, toprevent any alternating current from en-tering the batteries and to prevent anyirregularities in the battery voltage to betransmitted to the tubes. The first ismerely to reduce the common impedanceof all the circuits, since a condenser oflarge capacity has a much lower impe-dance than the resistance of the batteriesThe second is to minimize as far as pos-sible the noise which will result from ir-regular voltage supply. This refers withparticular emphasis to the plate battery.Condenser Cl, Fig. 4, illustrates the useof a large by-pass condenser across theplate battery.

Filter CondensersFixed condensers are also used in in-

termediate frequency filter transformersas illustrated in Fig. 4, by the condensersacross the secondaries of transformers T1and T2 and by C3. These are essentiallytuning condensers and should, therefore,be of a good grade. Their capacity ofcourse depends on the desired intermediatefrequency and on the inductances acrosswhich they are connected. The valuesare determined in the same manner asthe required maximum capacity of a tun-ing condenser in the tuner for a givencoil.

Neutralizing CondensersFixed condensers of very small capacity

are also used in circuits employing someform of capacity neutralization, as forinstance the neutrodyne (Fig. 5). Thesecondensers must be very small, since theymust be of the same order of magnitudeas the capacity between the grid and theplate of the tube. This is about 10 micro-microfarads. The correct value of coursealso depends on the manner in which itis connected. If it is connected betweenthe grid and to a point on the secondaryof the transformer following the tubewhich makes the inductance of the pri-mary and that part of the secondary which

EASTERNVoc-VE COILSere euhrsirety licensed by Rxir nM. B. Sumner for his nevevolutionary. on-regenera

tire tour -tube RXI Weeddescribed In this issue. Per set. $6.00

Eastern Pickle Bottle Coilsare also designed for perfect performance In thefollowing circuits:SUPERDYNE ($8.00 per set). BROWNING -DRAKE ($8.00 per sat). ROBERTS ($8.50 perset). TUNED R. F. CIRCUITS ($8.00 per Rill).

Certified by Herman Bernard.At your dealers or direct. postpaid.

EASTERN COIL CORPORATION22 WARREN ST. NEW YORK

Mailing ListsWill bele yea learessee walessend for F Wain Omanmuses sod pekoe en (demigodmom of par MO promotivememoir. - NstlouL Mate,Meal - IdleMaala. Moto -glom, Busies. Tema

44C7 ."."e 5c eachle rafted313 N.Inn, St


is below the point, then the neutralizingcondenser should be the same size as thecapacity between the grid .and the plate.Of course it can only be found by experi-ment. A neutralizing condenser having anair dielectric is the best, but most of thosethat are obtainable have glass for adielectric.

Nothing Equals Diamond,Fan's Verdict After Tests

DIAMOND EDITOR:I have just completed the Diamond and

have not heard anything that will equalit. I have built several sets, including theSuperdyne, but none of them came up tothe Diamond. The tonal quality, volumeand selectivity are exceptionally good.

The first night I tried it I tuned ineighteen stations: WHAT, WBBM,KOIL, WMBB, WHT, WOS, KDKA,WLS, WCCO, WTAS, KOA, WEBH,WHO, WHAD, KTHS, WJJD, WCEEand WSAI. I have had dozens of themsince that. All these stations come in onthe speaker regardless of static. I amusing home-made coils, basket weavetickler and diamond -weave RFT with avariable primary. The audio circuit con-sists of three stages of resistance coupledamplification using 96 volts. 120 on plateof last tube. The volume from this com-bination is tremendous.

I am pleased with this circuit and thankHermand Bernard for this masterpiece.Will send pictures as soon as I get mycabinet dressed up. I am a constantreader of RADIO WORLD.

ROY J. SMITH,925 Eighth Ave., So.,

St. Cloud, Minn.

Surprise of His LifeEnjoyed by Engineer

DIAMOND EDITOR:I promised myself not to be surprised at

anything in radio. I've built twenty-sevensets of various kinds and out of curiosityhooked up The Diamond and I receivedthe surprise of my life. I wasn't expectingvery much, because it was hastily throwntogether just to get an idea of what itwould do in selectivity, distance and qual-ity. I got all three. WTAM was on duringthis "fishing" test and this is a powerfulstation about 15 miles away. I got throughthem for Troy, which is only 10 metersapart, and that without interference.

Following is a list of stations received

FOR "FANS" FOR "HAMS"nIII1 now de -pas. Radio NEW 62 -page booklet of

Wale. including all arrny end nary Ire ns-the bent and leant Rita. witting apparatus and rots -Parts and ex.:modes for cellsneous medal. f o rbreadeut receiving sets. -hams" such as W. Z.Lowest prices in the won- Choice Colts. Generator.,try. Resistance Bores, se.

More than 1,0 00,00 0 fan. and hems make my ewetheir headquarters-get thee Woks and find out why

Writs for either or both

sssSouthStateStreet

Dept.R. W. IIChicago

ls-

on loud speaker between 9 and 11 p. m.one night: WBZ, Boston; WEAF, NewYork; KDKA, Pittsburgh; WTAM,Cleveland; WJR, (WCX) Detroit; WSB,Atlanta; WSMB, New Orleans; WHAD,Milwaukee; WPG, Atlantic City; WTAS,Elgin; WJRC, Cincinnati; WCAE, Pitts-burgh; WCAP, Washington; WREO,Lansing; KFKX, Hastings; WSAI, Cin-cinnati; WHAZ, Troy; WLW, Cincinnati;WOS, Jefferson City; WCBD, Zion City.

While this is not a new circuit I amsure your magazine, which I read re-ligiously, deserves a great deal of creditfor bringing it to public notice in suchan effective way.

I appreciate having a set that has real

A REAL AUDIO AMPLIFIERThat does the workOnly VAMP Postpaid

Will positively Immensetha nese and melees elany tube at eyelet atthree es four times. la udible elsnele hello esto wake melee.. de-plete as Illustrated. In -o WI es tube. Rod parts

nd workmanship. Pane -UMW. belutely Soar -anted.

TRELLCOTT CO. ti II Hal. AMINLau In DN. KY.

DX powers, selectivity and excellent qual-ity.

E. A. FISHER,City Engineer,

City of Lakewood, 0.

Diver on North Sea FloorBroadcasts What He Sees

HELIGOLAND, GERMANY.The recent experience of WIP, Phila-

delphia, broadcasting from under waterat Atlantic City, was repeated by a Ger-man station with fine success. A diver,on the floor of the North Sea, spoke intoa microphone and thousands listened.

All Hamburg, 100 miles away, listenedto the diver's description of the sea floor.

NEW MAIL ORDER DEPARTMENTThe Rix Radio Supply House, 5505

Fourth Avenue, Brooklyn, N. Y., hasadded a mail order department for thebenefit of their out-of-town customers.They will carry only standard parts, sup-plies and sets and will cheerfully refundon any unsatisfactory transaction. Theymake it a practice to fill orders the sameday they are received.

Build the PowertoneA 5 -Tube Set of Surpassing Charm.

It is easy to tune-only one dial. Ithas wonderful tone and volume. It ismarvelous for bringing in far -distantstations.

Use the Official Kit or buy the Official set, I

both licensed under the Hogan Patents. .'It Iles a Soul for Music."

Official Boxed Kit, Including

$2 Sal Li'9"ed

Set

. mad. is I".50drilled and engraved panel and I) tory of same. parts; installed le

hookup cabinet

Inquiries Invited Irons the Trade.

BRUNO RADIO CORPORATIONDept. W.

Telephone: Cortlault 4467

223 Fulton St. N. Y. City

cLAIOr 11ER

ff,%e1111(11'

Ask about theClarostat, heart ett h e Clarottmer.

Specified For TheFamous Thoroughbred

RRADIO World experts, Hayden and Ber-nard, specify the CLAROTUNER for

the famous "Thoroughbred" circuit. Morethan that, they lay the success of thiswonder circuit to the CLAROTUNER.There is no need of saying more.CLAROTUNER mounts with only onehole. It incorporates the latest low lossdesign features. Ask your dealer aboutit! Model TCH $4.50.

If distribution has not yet reached your dealersend your remittance direct to

American Mechanical Laboratories,inc.285-7 N. Sixth Street, Brooklyn, N. Y.


How to Make the Coilsfor the 3 -in -1 Receiver

(Continued from page 4)that way. The diametrical oppositionfacilitates connections later.

The primaries consist of 15 turns eachand are put on in the same fashion, not inthe center of the form but nearer one

THE RAMBLER SIXA REAL PORTABLE

Volume, Clarity, Portability, Durability andBeauty Unequalled

Lightest in weight. 21 pounds.Smallest I. We. 14,9.209s, inches

LISTPRICE $80.00

If your dealer cannot make immediate de -..very we will ship direct from factory sameJay your money order or check is received.

American Interstate Radio Service183 Greenwich Street, New York City

Distributors, Jobbers, Dealers. write forspecial trade terms.

EVERY SET BUILDERNEEDSTHIS ger"Morsing Bus -Bar Union"

Makes for quick assembling. Repairscan be made by suing Morning Bus -BarUnion without taking set apart.

Assemble round or square Bus -Bar andsolder three wires at a time. Order No.1 for No. 14, No. 2 for 12 wire. Send25 cents for enough for building DM setsor ten for PM.Newark Watch Case Material Co.15 Ward Street Newark, N. J.

DISTRIBUTORS WANTED

WIDE SEPARATIONOF ALL STATIONS

plate construction. exclusively a Wadee. spreads all stela., neatly er 3601, pee dial. Gives wider SePaestion of Oath". ban ordinary rotor plate types of straight Iliaiequency condensers tieing ISO degree dials,Deellied for all critical circuits where sharpicing is essential.Wade condensers cover the entire broadcast bend.men down below 200 meters.All slue. complete anti 4 -inch silvered 960 degreeteenier dial, 91-1 ratio far:

Short Wave .000125 mfd $7.50.00025 mid. 7.75.0003 mfd. 8.00

At your dealers. otherwise and purch.e Primand you will be supplied

WADE RADIO CORP.1819-C BROADWAY NEW YORK

*DP

THE PANEL VIEW of the 3 -in -1 RFReceiver.

end, and with terminals on the same axialthe inside, so that the head will stickplane.

See that all windings are in the samedirection.

The Insertion ProcessNow take a secondary form. Drill a

3/16" hole, or one about that size, 1/2"away from the nearer pinhole of a sec-ondary terminal. Insert a 3/16" screw,about h" long, round or flathead, withlug next to head and with the head oninto the air space inside the form, knownas the core. Pick up the wire terminalthat is close by, scrape off all the insula-tion for 1/2" lengths, wind two turns of thewire around the screw, tighten the wirewith tension applied by pliers, and screwdown a hexagonal nut firmly against thelug. Snip off the excess wire, that is, theslight length dangling on the screw. Re-peat the aforesaid operations for the otherterminal of the secondary. Then soldereach of the two joints separately (nottogether, of course). The soldering willbe very important, for it will insure ex-cellent electrical contact for screw, nut,lug and wire. Try to do the soldering sothat the four elements are united. Thisis harder than it sounds. It is safe toomit attempting to solder to the screwitself, as the contact it makes with thenut is an excellent pressure one, andsoldering scarcely can improve it.

Primary DistinctionsAs for the primary, a little different

procedure is necessary, as follows: (1)two holes are drilled for the screw in-sertion 1" apart, ;V from the circumfer-ence, at that line nearer the winding;(2) the screws are inserted in oppositefashion than that employed on the second-ary, i.e., with heads on the outside andshanks, nuts and lugs in the core; (3)one of the holes will be 1/2 " from thebeginning of the winding, and the otherhole will be determined by its positionrespect to the previous one, regardlessof where the other primary wire terminalis.

The wire having been threaded throughthe pinholes it is turned through one bole

AMBASSADOR4 -TUBE, $25.95; 3 -TUBE, $1795

With tubes, cabinet; 1 -tube sets,$2.95 up. Edzin Radio, 675 6th Ave.Chick. 10385. Open eves., Sundays.

ZILTR7T-VeR_niER,TUNING'. CONTROLAw DIAL ON edeicAoyou CN. fENC/LRECORD THE .TAI IONS. GEARED 20 I, I SILVERr CIS" 52 AO - GOLD' FiNtSel So So

PHENIX RADIO CORP., 1.16.E East 25 Si., N.Y.C.

"HOW TO MAKE-"The following illustrated constructionalarticles have appeared in recent issues ofRADIO WORLD:Sept. 27- A 1.11be Cri 011 Hen.Der 13-The World's 5104,1, >1 T Set toLieu:. P. V. R..urk,Dec. 20-A 1 -Tube e

by Hermon Bernardtector. by Ch. hi 91....

Dee. 27-A 2 -Tube Vial. o-1.1P. V. O'Rourke. l oioia s bk.Def Flex

Jae. 3, 1925-A 3 -Tuba Portable Taal Needs h..OULAteee Aerial, by Abner J. Gel...

las. 7-S $25 1 -Tube DX Wonder, to Abner JGedula.

Jae. 24-A Selective $15 Crystal :Pet, by Brews,Lee. A Varlometer-Tuned Red.. by Alm,J. Gelula. An $18 1 -Tube DX Circuit fathe Beginner. to Feeder Rohatkin.ha. 31-A Regenerative Neutrochne for Me,.DX. by Abner J. Gelid, A 'Thansovoittnenico2 -Tube Set. by H. K Wright. An Raperit:Dental Refl.. by Lieut. P. V O'Rourke.Feb. 21-A 1 -Tube Reflex for the Novice. byFeat. Rofpatkin. A Set Ion Profession.Folk, by Lieut. P. V. Oltrourke. A Honey -nab Crystal Receiver. by ilayelohd B Wailes.Feb. 28-A Set That Does the Ideal Povaible.With ti Tubes. by Thom. W. Benson. ThreeResistance Stages of AF on the 3-CtreultTuner. by Albert Edwin Sot..

March 14-The Rellegesi 3-Circult Tuner That YouCan Log, by Harman Bernard. The RightWay to Put Coils and Candensers to a Set,by Byrt C. Caldwell.

Mareh 2I-A Variable Leak. by Herbert leHayden. A 4 -Tube, 9 -Control Set That Ginathe Most DX. by Limit. P. V. O'Rourke.

April 18-The Diamond of the Air (Part 31. byHerman Bernard. The -Tube Pressley Super -Heterodyne (Part 1). by Thom. W. Benson.An Easy D Coil, by Jack Norwood.

May 2-The 'fwitiples. by J. K AndersonMay fl-A Set to Cot Static. by Feder Hal -pandit. Tani,' Circuit with Resistance AF.by H. I. Sidney. A Ptah -Pull AF Ampli-fier, by Lt. Peter V. O'Rourke.

June 6-rhs Smokestack Portable. by Neal Fits-... A nd B Battery Eliminators. VeinsDC (Part I). by P. IL Edelman. A Wave -meter. by Lewis Winner. 1111 L.11D Broad -mating Stations.funs 13-Simple Short -Wave Circuits. by Herbert

E. Hayden. A Simple Push -Pull Rheuetat. byA. C. G. Force. A and B Battery EThoinatore.Vane AC (Part 2). by P. Pi Edelman. APortable duper -Heterodyne. be WainwrightAstor.

lune 20-The Diamond as a Reflex. by HermanBernard. A 2 -Tube Pariah'. Relies, byHerbert E. Hayden. A Relies for 69 TypeTubes. by I- R. Barbi..June 27-The Pocketbook Portable, by BurtonLindhelm. The Power Han. Set. by JohnL. Lesson au Learning the Cade.July 4-The Handsome Portable. by Herbert KHayden. The Freedom Refl.. by Capt. P V.O'Rourke. 8 -Tube Super -Heterodyne, by Abner

J. Ge luta.July 11-The Baby "Super," by J. E Anderson.

A 1 -Dial Portable Receiver, by Capt. I'. V.O'Rourke.July I8-Anderson's 6 -Tube Super -Heterodyne.

The 3 -Tube Marconi Receiver. by Perry War-ren. A Good Battery Connector. by HerbertE. Hayden.

Aug. I-Enormous Volume on DX &adobe. bySidney H. Finkelstein. The MetropolitanLocal Set, by J. E. Anteroom 4 -Tube DXDivided Circuit, by Herbert R. Hayden.Series and Parallel We... by HermanBernard.Aug. 8-The !halation Reflex, by Capt. P. V.O'Rourke. The Mldget-A 3 -Tube Set inSewing Machine Cabinet. by Herbert K H.-

Oen. How to Build Your First Set, byHeenan Bernard. 3 -Year -Old Wins DXStake, by Lewis Winner.Aug. 15-A 2 -Tube Speaker Reflex, by Brewster

Lee. Capt. P. V. O'Rourke's Favorite AudioAmplifier. A Set That Taxes Ingenuity. byLeiria Whiner. The Loop Jack in The Dia-mond. by Herman 'Lenard.

Aug. 22-The 5 -Tube Diamond, by Fildney E.Finkelstein. A Home -Made Toroidal Coll, byGeorge IL Hostetter. The Electrostatic Re-generator, by Percy iVarren. Crystal Sets ThatYou Can 1,g. by Herman Bernard.Aug. 29-The 1 -Dial Powertune. by Herman Ber-

nard A set a Baby Can Build, by HerbertE. Hayden. A Fine Meter Switchboard. byLewis Winner. A Powerful 1 -Tula Set, byParry Warren.

Sept. 5-The loop Model Powertone. by HermanBernard. A 5 -Tube Geared Reale., by LewisWinner. The 11X120 Model Diamond. byCapt. P. V. O'Rourke.

Sept. 12 --The 1926 Model Diamond of the Air.(Part 1). by Herman Bernard. An Q0ellIstingWavemeter, by J. Ifs Anderson. A 25 -to -110Meter Receiver, by Sidney E. Finkelstein.

Sept. 19-Dianiond of the Air (Part 2). by Her-man Bernard. A I -Dial. 2 -Tube Speaker Set.by Perry Warren. A Tube B Battery Elim-inator. by Lewis Whiner. A liome-Made Vol-ume Com Yol, by Herbert E Hayden.

Sept. 26-The 8 -Tube Super- Hetenidyne, by Sid-ney E. Finkelstein Dimond of the Air (Part3), by Herman Bernard. The 5 -Tube Brown-ing -Drake, by Capt. P. V. O'Rourke. A '-Control Regenerative Set. by Percy Warren

Oct. 3-The Thordareon-Wade Set (Part 1). StyHerman Bernard. A Fixed Grid Leak, byHerbert It. Hayden. Trouble Shooting forDiamond of theOct. 10-litakune for the Shari Waves, by Percy

Warren. The 3 -Tube. 3 -Circuit Tuner, by11pt. P. V. O'Rourke. The DX Set ThatThrilled Jack. by Lewis Winner. The Thor-darson-Wade Bet (Part I). by Herman Ber-nard.Oct. 17-The Thoroughbred (1 -Tube DX Set,.by Herta. Hayden O'Rourice'e Farorlte SWSet, by Capt. INtor V. O'Rourke. TheThordersoh ude Set I Part I/. by HermanBerta

ViN. Trouble Shooting Annie.

Any copy. 15e. Any 7 copies, $1.00. All then34 copies for 34.73. or start subtalptIon withany issue. Radio World, 143 West 45th Street,New York City.

October 24, 1925 RADIO WORLDonce again to come out through the core,is carried to the screw, twisted around,the nut is tightened over the wrappedwire, and the soldering is done. Thephotographs confirm these directions.

The Directional GoalIt is important to insert the primary

inside the secondary so that the windingsare in the same direction, because the

tetillartTMPllOeVIALIMPROVES RECEPTION

Glees wmnderful results alaiany radio mt. Not attached to, but mere-ly Placed under the telephone. Prim OneDollar. Complete IrlOt Insulated wire notsimple instruction, At Your Dealer orMailed C.O.D. on S dais approval.

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polarity question as affecting winding ter-minals is based on the assumption ofunidirectional winding.

You may wind two coils in the samedirection, but if you put them in inductiverelationship so that the beginning of oneis nearer the end of the other, then thesame effect is obtained as if the two wind-ings were in opposite directions. It is

very easy to determine the direction, evenit you have put aside one coil just wound,and made another without any attentionto how the previous winding was made.Even if by mistake you wound them inopposite directions, by correctly placingone coil inside the other the same effectexactly may be gained by the methodof insertion. Take any given coil. TakeTither terminal thereof. Sec the directionin which it points. Call that the begin-ning. Look at the other terminal. Thatnecessarily points in the opposite direc-tion on the same perpendicular plane. Toclarify discerning this, regard the end ofthe wire as the point of an arrow. Nowtake either terminal and consider thatthe beginning, the other the end. if youtake a terminal of the other coil, so thatthat points in the same direction as thebeginning of the first coil, and insert thesecond coil inside the first one, so thatboth unidirectional terminals arc neareach other, you will achieve the desiredgoal.

Point of Possible ConfusionOne point of possible confusion arises

because the secondary has a fractionalturn. Diametrically opposite terminalspoint in the same physical direction, butlet your imagination carry the wire aroundthe extra half turn and you will be guidedright.

The Mounting HoleNOW, the primary inserted in the sec-

ondary, drill a hole through both forms,from the circumference, opposite where

the primary lugs stick out. Regard theselugs as one side and determine the posi-tion for the single hole through bothforms by putting it on the diameter wouldleave the primary nut holes on the right-hand side, say, the new hole on the cen-tral diameter, with the right-hand sideunidentified. This new hole, through bothforms, is for another screw and nut, whichwill be used to fasten an angle iron tothe subpanel.

As all three coils, L112, L3L4 andL5L6, must be made alike, be careful tocount the turns. Confirm this by check-ing and rechecking.

[Part II, the conclusion of Sidney E.Finkelstein's article on the construction ofthe 3 -in -1 RF Receiver, will be publishedin next week's issue of RADIO WORLD, datedOctober 31.]

RECENT BACK NUMBERS of RADIOWORLD. I5c each. RADIO WORLD, 145 West

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28 RADIO WORLD October 24, 1925RESULTS EDITOR:

The writer, who has been buying yourmagazine regularly from the newsstandfor at least a year, has noted the corre-spondence you have had with differentsubscribers concerning the "Reflex for theNovice" (Feb. 21 issue).

Might say that I have been experiment-ing and building sets for the past fouror five years from Crystal sets to Super-Hets and in fact have built three of theReflex sets referred to. I am going togo on record whether it means anything

Waage "B" Eliminator solves the"B" Battery problem. Use 20I -AType tube; old tube that lights*nil do-A.C. (Without Tube) Z01 -A

Type =SOFor New U.X. Tube $35.00

A. H. WAAGE. 6 Reade St., N. Y.Guarantee money back if not satisfactory.

-Brune Magic DialMakes any semi-circular Oat* eon -denser tune Ilk* theatraightline f r -queasy type. Nogears, no backlash.

$250BRUNO RADIO CORPORATION

Dept. WIN III Fulton St. New York CityInquiries Solicited Irons the Trade

$4.75POLLO

A loud speakerof surprising musi-cal quality an dvolume. In theclass with high -p r i c e d speakers.Artistically d e -signed. Swan neck

type. Adjustable unitwhere volume and toneare at all times underperfect control. Sendno money. Just pay thepostman.

RIX RADIOSUPPLY HOUSE, INC.

OEM 4th Ave. Dept. 43 Brooklyn, N. Y.

RESULTSReaders report on their ex-

periences with sets built fromhookups published in RADIOWORLD, Address Results Editor,RADIO WORLD, 145 West 45thStreet, New York City, and sendphotographs of sets, if possible.

or not to you by saying that this Reflexis about the sweetest set that I have everbuilt. Stations all over the country comein with a bang and I have no difficultywhatsoever in separating and bringing inanything within 1,000 miles.

I had practically the same result withtwo other sets made from the same cir-cuit. The fellow who has the courageto knock the circuit, in my opinion, hadbetter go back about six years and tryand build a crystal set

I subscribe to four radio magazines andpurchase practically every issue of everymagazine that is published and I franklystate that I consider your magazine thebest that is put before the public.

H. A. WOODCOCK, Sec'y.,Arthur F. Houts & Co., Inc.,

80 Maiden Lane, N. Y. C.

RESULTS EDITOR:

One day I got your magazine. I readit from A to Z, inquired from some ad-vertisers which duly answered me andalso sent me their goods.

Then I built a set you described andafter a few days I was hearing WOC.Certainly that Davenport station came infine and clear, full of dreamy music, andwith volume enough to fill up all the room.The distance is 2,600 miles and across thesea of static that divides our countries.It was through your Superdyne, a pictureof which I am enclosing herewith.

I am now a subscriber to your magazine.AMANDO CESPEDES MARIN,

Heredia, Costa Rica, A. C.* *

RESULTS EDITOR:

I just completed the Midget (August 8issue) and added one more stage of

Radio Batteries-they last longer

transformer -coupled amplification and DXand selectivity is great. I get WWJ,WGY, WSAI, WGN, CNRO and all sta-tions on the speaker within 1,000 milesloud enough to hear it a block away. Iam very much satisfied with my set.

In closing, I wish to extend my con-gratulations to Herbert E. Hayden and toRADIO WORLD.HAROLD FRIEDMAN, 812 Market St.

Chattanooga, Tenn.

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-RADIO NEWS er -RADIO DEALER or -for one year (regular mice-RADIO JOURNAL or -for II numbers)-POPULAR RADIO or -RADIO (San Francisco) or _...d select say d the other-RADIO BROADCAST or -THE EXPERIMENTER on-SCIENCE AND INVENTION or -RADIO AGE -sins publications for twelve months.

two publications-Add 01.0. a year extra for-Canadian or Foreign Postage.-Present RADIO WORLD subscriber.-can take advantage of this offer by--extending subscriptions ow year-if they send renewals NOW.

RADIO WORLD'S SPECIAL TWO -FOR -PRICE-OF -ONE SUBSCRIPTION BLANKRADIO WORLD, 14S Wept 45th St., N. Y. City.Enclosed find 56.00, for which send me RADIO WORLD for twelve months (52 numbers), beginningand also without additional cost, Radio News, or Topular Radio, or Radio Broadcast. or Science and Invention, or Radio Dealer, or Radio (Sas Franca.co), or The Experimenter, or Radio Journal, or Radio Age (or $10.00 for two yearly subscriptions).

imamate if renewal. Name

Offer Good UntilNovember 10, 1925.

Street Address

City and State


THE SET A. C. Marin, of Costa Riga, built, and which brought in WOC, 2,600 milesaway, on the speaker. See his letter on opposite page.

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Sets and PartsSTONE ELECTRIC CO., 714 Pine St., St. Loofa Me.All Mdse. F.O.B. St. Louis, Mo. Dept W

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WHYResistance Coupled

Amplification?

BECAUSE this method of amplifi-cation is the only way to procure

quality of tone without the slightestdistortion. The Daven Super -Ampli-fier can be conveniently put into anyexisting set. Use it also in the newset you are going to build.To increase volume 50% and have nodistortion use Daven High Mu Tubesin Resistance Coupled Amplifiers.Prices-High Mu -20, $4.00. Mu -6 (forlast or output stage), $5.00.

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_visa nor rrmmry mrrrw,nc r.c nanera

Listeners Hear PlaneAs WNYC RebroadcastsSuccessful rebroadcasting between an

airplane and a radio land station wasput on the air by army bomber AB -6 andWNYC, the municipal broadcasting sta-tion, New York City.

The broadcasting station established anoutpost at the Mall, Central Park, wherea special receiving set and remote controlmicrophone were installed. The bomber,escorted by four others flying in formation,left Mitchel Field at 7 o'clock and itsradio signals were immediately picked upby the operators at the Park. At 7:35P. M.; the appointed hour for the demon-stration, WNYC called the plane, andLieutenant Wolff, the observer, repliedimmediately on wavelength of 430 meters.

Thomas H. Cowan, broadcasting super-visor of WNYC, was heard as he spoketo Lieutenant Wolff and replies from theplane were picked up at the Park andalso broadcast from the land station, thuspermitting all listeners to hear both sidesof the conversation on the same wave-length.

Station WFLA to Openin Florida Nov. 1

November 1 will see the advent of oneof the largest broadcasting stations inthe South, erected at Boca Raton,Florida, by the Mizner Development Cor-poration. The station is being built under

the supervision of George Sheffield ofNew York. Its call letters will be WFLA.

Broadcasting with an output power be-tween 1,000 and 2,500 watts, its broadcastfeature will be outstanding events fromPalm Beach and other towns nearby.

MORE POWER TO WLSWASHINGTON.

The Department of Commerce hasauthorized WLS, Sears Rosebuck Com-pany, Chicago, to increase its power from500 to 1,500 watts.

EFFICIENCYThat Meets the Requirementsof Eminent Radio Engineers

Apex Vernier Dials are more than mere knobs." In reality they are instru-fents endowed with an ultra degree

efficiency. Their rich elegance offinish lends a touch of striking attrac-tiveness to any set. Precision of pro-duction and of operation makes agood set a better set ;providing greaterrange of selectivity - positiveness ofcontrol - and utmost simplicity oftuning in most difficult stations.Ratio12 to 1. Clockwise and counter clock-wise. No backlash. Royal Brass finish4 -inch $2.00. 3X -inch $1.65. Satin sil-ver Finish 4 -inch 52.50 -3% -lath $1.90.Gold (24K) finish 4 -inch $3.50 - 3M -inch $2.50. Your dealer has them.

APEX Rheostat Dials750, 85c and $1.00

APEX ELECTRIC MFG. CO.Dept.l023 A

1410 W. 59th Street CHICAGO

5Tube Radio Set

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575.00 value, fully built and wired in beautiful mahogany cabinet of latest design. slopingBakelite panel, Satin finish, handsomely etched and engraved. Constructed of the finestlow -loss condense7i conon tend socketaihBatlite baaheihiard panel and dials. 529.50 for set

'Its set withp llllllllllllllllllllllllllll tUfamotus5AltlisserIcan Bell loud speaker withadjustable unit, 2-45 volt "B" batteries, one guaranteed 100 Ampere Hour. Storage -A"battery, cable for battery connection, 5-201A tubes, aerial andground equipment, and everything complete ready to set upand operate. Nothing else to buy. Price $59.75. 'Trans-portation charges extra. Shipping weight 100 lbs.

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Contains thommtla of haunting in radiosets, mm1-finished seta and radio kits of all

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In esbiba !s'jP,1,2-1°:"Si?"1stenuteeple-Nino)... Coast to meatrm.. Also contains everythine In reolo ettO-Vrisnr=1"Vreernirlierr.4"eo. lt1122rittYotheripert; you may want for unodrovriur your set,

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1926CatalogContaining

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30 RADIO WORLD October 24, 1925Removes Horn From Set;

Gets Music Just the SameWASHINGTON.

Another queer freak in radio has beenreported from Paterson, N. J. WilliamBotbyl, an engineer, was trying out anew speaker recently. In adjusting it hedetached the horn from the set. To hisamazement, the music continued_ Thehorn was removed to the next room, butstill the music continued. Experts of theneighborhood were called in, but no ex-planation could be offered. The set wasa home-made affair.JSMULTV'PLUG

THE STAN DAI4 W}'ON N ECTOR

HOWARD B. JONES1118 S. CANAL STREET CHICAGO

KESTER Radio SOLDER(RosinCorel

If your dealer cannot supply yousend us 25c in postage -

CHICAGO SOLDER COMPANY,,CHICAGO. U. S. A.

Five New StationsWASHINGTON.

Five new class A stations have justbeen licensed by the Department of Com-merce, while one station has been trans-ferred from class A to B. The transferredstation was WGHP, owned by GeorgeHarrison Phelps, Inc., of Detroit. WGHPwill continue to operate on 270 meters buthas increased its power from 500 to 1500watts.

The new class A stations follow:Station Owner Location M. W.KFXY-Mary M. Costigan,

Flagstaff, Ariz. 205.4 50WJBK-Ernest F. Goodwin,

Ypsilanti, Mich. 233 10KFJZ-Southwestern Baptist

Theological Seminary, FortWorth, Texas 254 50

WJBN-St. John's Ev. Lu-theran Church, Sycamore,

256 10WTAG-Worcester Telegram

Publishing Co., Worcester,Mass. 268 500

TRANSFER FROM CLASS A TOCLASS B

WGHP-G e orge HarrisonPhelps, Inc., Detroit, Mich.. 270 1500

POWERTONESET

This is the receiver thatthe whole family will enjoytuning. Just one dial toturn. Volume aplenty,quality superb, rang. re-markable! Sold in cabineton 10 -daymoney -back $39.50guarantee ....With Bretwood VariableGrid Leak installed..$40.50

Five Tubes

or KITThe same genuine licensedparts as used in the factoryset, but without cabinet.Easy to build. Drilled andengraved panel. Hookupsincluded in the $29 50boxed kit......With Bretwood VariableGrid Leak $30.50

RADIO DIVISION, COLUMBIA PRINT145 WEST 45th STREET NEW YORK CITY

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RETAIL ANY SIZE WHOLESALEPRICE LIST MAILED ON REQUEST

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The Newand BetterDiamondof the Air

The Bernard Audio Amplifier

DX, Selectivity, Volume and Quality-All Marvelously Combined InRADIO WORLD'S 1926 Model

DIAMONDOF THE

AIR5 tubes, including Bernard AF hookup,Sept. 12, 19 and 26 issues of RADIOWORLD, including picture diagrams ofwiring.

Send 45e. for these three numbers orstart your subscription with the Sept.12 issue. Send SO for yearly subscrip-tion and get these three issues FREE.Address Circulation Manager, RADIOWORLD, 145 W. 45th St., New YorkCity.

1925 BACK NUMBERS OF RADIO WORLDWANTED: Mail us copies of any of the fol-lowing 1925 issues of RADIO WORLD, and wewill send you a copy of a current issue for everycopy sent us: January 10, February 7, March 21,28; April 4, 11; May 30, 192S.

LISTEN IN every Friday at 7 P. M. and bearHerman Bernard, managing editor of RADIOWORLD, discuss "Your Radio Problem," fromWGBS, Gimbel Bros., New York City, 315.6meters.

RADIO WORLD'S QUICK -ACTION CLASSIFIED ADS.19 CENTS A WORD. 10 WORDS MINIMUM.

3 TRIPLE TESTED SILVERED DETECTORAmplifier WW -201-A Tubes, with Standard Base,for $4.25, or $1.50 each. Guaranteed. WilliamsDistributing Co., 4301 Third St., Louisville, Ky.

DINING AND SLEEPING CAR CONDUCTORS(White). Exp. unnecessary. We train you. Sendfor book of Rules and application. Supt. RailwayExchange, Sta. C, Los Angeles.

PATENTS-Write for free Guide Books and"Record of Invention Blank" before disclosinginventions. Send model or sketch of your in-vention for our Inspection and Instructions Free.Terms reasonable. Radio, Chemical, Mechanical,Electrical and Trademark experts. Victor J.Evans & Co., 924 Ninth, Washington, D. C.

HOOK J.JPS-A lot of them, some of whichare set . to suit your purpose, appeared inRADIO WORLD dated August 15. 15c a copy,or start your subscription with that number.RADIO WORLD, 145 West 45th St., N. Y. City.

HOW TO BECOME AN AMATEUR OPER-ATOR-A comprehensive, illustrated article ap-peared in issue of June 27, 1925. 15c per copy, orstart your subscription with this numberRADIO WORLD, 145 West 45th St., N. Y. C.

"LIBERTY AFLAME" and other patrioticverses. By Roland Burke Hennessy. In cloth,$1.00. Columbia Print, 145 West 45th St., N. Y. C.

HAVE YOU ANYTHING TO SELL OR EX-CHANGE? Use RADIO WORLD'S ClassifiedDepartment and get great results. toe a word.RADIO WORLD, 14S West 45th St., N. Y.

A 1 -CONTROL PORTABLE, by Capt. P. V.O'Rourke; A Baby Super -Heterodyne, only 4Tubes, by J. E. Anderson; A More PowerfulDiamond, Still only 4 Tubes, by Herman Bernard.Other features in RADIO WORLD, dated July11, 1925, 15c a copy, or start your subscriptionwith that number. RADIO WORLD, 145 West45th St., N. Y. C.

HOW TO BUILD THE POWERTONE, 1 dial,5 tubes, described in RADIO WORLD, issues ofAug. 29 and Sept. 5. Powertone Trouble -shooting,Sept. 12. Send 45c for all three. Special diagramsand "blueprint in black" included among the manyillustrations. RADIO WORLD, 145 West 45th St.,N. Y. C.

HOOK-UPSI-A lot of them, some of which aresure to suit your purpose, appeared in RADIOWORLD dated Aug. 15. 15c. a copy, or startyour subscription with that number. RADIOWORLD, 145 West 45th St., N. Y. C.

PULLMAN CONDUCTORS, PORTERS. Menwishing such positions can easily qualify, informa-tion free. Supt., 123C, Railway Exchange, KansasCity.

COMPLETE LIST OF BROADCASTING STA-TIONS appeared in RADIO WORLD dated Oct.3, 1925. 15c per copy, or start your subscriptionwith that number. RADIO WORLD, 145 W. 45thSt., N. Y. C.

HAVE YOU BEEN AWAY?-Have you missedany of the summer copies of RADIO WORLD.We can supply you with any copies of RADIOWORLD published during the summer at ourregular price of 15c per copy, or any seven copiesfor $1.00, or start your subscription with anynumber. NEWSDEALERS: We will fill yourorders for back numbers at regular wholesaleprice. RADIO WORLD, 145 West 45th St., N. Y.City.

ANDERSON'S 6 - TUBE SUPER - HETERO-DYNE, by J. E. Anderson; the 3 -Tube MarconiBroadcast Receiver, by Percy Warren; How toMake a Good Battery Connector; other featuresin RADIO WORLD, July 18, 1925. 15c a copy, orstart your subscription with that number. RADIOWORLD, 145 West 45th St., N. Y. C.

October 24, P)25 l A 1) 1 0 \\,' (1 I. 1)

Coast to Coastooe`CP.'

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For Bretwood Variable GridLeak Alone. Send 50c extra ifCondenser -Leak Unit is desired.

North American Bretwood Co., 145 W. 45thSt., New York City:-Enclosed find $2.00.Send one Bretwood Variable Grid Leak -Condenser Unit, prepaid, on 10 -day money-back guarantee.

Name

Street

City State

Made in England

Guaranteed Precision Range, 1 to 10 meg.

IF distance is your goal the BretwoodVariable Grid Leak is the Magic

Means of Achieving it. And the Bret-wood Low -Loss Grid Condenser -50cextra-increases the detector tube'ssensitivity.

North American Bretwood Co.Telephone: Bryant 0558

145 West 45th Street New York CityMembers of the Trade, Write for Particular,

RADIO WORLD October 24, 1925

B -C -L

Build the 1926 Model

Diamond of the Air<Using parts certified by Herman Bernard, whodescribed the construction of this wonderful setin RADIO WORLD.

Herman Bernard

Complete Kit, including Drilled and Engraved Panel,Bretwood Variable Grid Leak, Bruno Coils, and GeneralInstrument (G -I) Variable Condensers.

Tgruno"99" 3 -circuit

66 f

tuner

wound onQuartzitefor .0005.

Used in theDiamond.

$5.50Genera nstrument (G -I) No -LossVariable Condensers,Pyrex or loolantite, all $2.95capacities

Geared Vernier, with dial, $1 extra

46

XThrnr11110

"55"

Matched radio -frequency coil foruse with the "99."Wound on Quartzitefor tuning with a.0005 mfd. condenser.

Strictly low -lee mad rifttypifying highest efficiency ..po

COMPLETE KIT for Herman Bernard'sI -Tube DX Set with SLF $7 75Condensers

B -C -L

7.50Same Kit, but with BrunoCondensers 539.50

PrUnD"77" 3 -circuit

tuner withpancake tickler.

For .0005.

$5.50

Betts & Bats Loop, CollapsibleT y p e. Very selective.Wound with strandedwire .25

The Weekly Catalogue of Guaranteed Parts and KitsCOMPLETE KITS

Hayden'. Thoroughbred (without @seine) 97.508-Telie Rule Reim 24.10"S 77" 3 -Tube DX 19.59Abauador 6 Tube 17.50Robert.' Keoekout 33.50B rowieleg- Drake 32.45B ernard Audio Amplifier 10.50

7.50Frahm. K It, mile and ****** secs

VARIABLE CONDENSERSB rno 3-mation (three .00025 tuned by one

moll.) $5.95.0005 mfd. Preferred 1.75Hanmaarlaad, 43 pl. vernier 2.95Manhattan for -less, .0005 cern 2.75U. S. Teel .00025, .00050, .0005, all cornier 1.95Wade .0005. 93; .00020 7.75Ammo Allman., SLF .00035 3.75Ammo A Routing SLF .0905 3.115Heath Radiant, aerator. II coP 1.95K leg Cardwell, all sap 2.95Sleeve Type Neutralizing Condenser .25Continental Midget 1.00

SOCKETS5 -Sono Shell for 1920 Model 52.504- Rang Shelf 2.003 -Gang Shelf 1.59Panel Mount. Triple 75.Federal 65.Bell. Standard Navy and 99 45eU X Adaptor, (No.- aid) .... .... 35e

AUDIO TRANSFORMERSThsrdarson Autoformer $4.25Federal 65. 654 3.75Eris 3-00-1, 0.10-I 3.50Therdarson 2.te I 3.50Therdarson 6-te. I 3.10Therdarson 341.1 2.95Jefferson Star 6.10.1 2.10Jeff Green Star 5 -to -1 1.85Reuland Lyrie 6.95Crescent 640-1. 3 -to I 2.25Ammo 4 % -to- I. AZ 2.50A 11.Amerinn 10-10-1 3.75A mortraa 15-t,-1 and 3-teI 3.05

3.95De onset 5.te-1COILS

"Bruno 66" 3-eireult Tuner"Bruno" FilterClerotuner

Bretwood Vert -able Grid Leak, $1.50.With Bretwood Low -Leas Grid CondenserAttached $2.00. 2.23 Fulton Street

$2.252.253.50

Apes vernierMarco hairline vernierVenus 4" vernierKurz Kasch Bakelite 4"UnivernlerB. M. S. vernierPathe 2. 3. 4"Ns -old 4"Amuratune

TUBESVenus Voltron 201A, 99 type..........R. C. A. Tubes UV201 A, UV109. WD12,U X12013 oFerest D V2. D V3, DV3A. 0V5

BradleyleakLEAKS

Fixed Leaks, all values

Antall. TypeGreeley Mallet.

RHEOSTATS"Brune" 8, 10. 20, 30 ohmsPuma. all sleetCutler -Hammer 6 ekeAIM.. 0, 20 or 30 ohmsKI maim. 6 ohmKhmer plain 6 ohBradleystatFade 6 or 30 ohmFrost 6 ohmF ..... I 6 ohm

Yankee 3-elreultFIXED CONDENSERS

Dub Iller 2.0 gildDuhiller 1.1 mfdDubiller 0.25 mid0.4111r .006 oddGeneral Instrument .001. .0005. .00025 454Grid Condemer .00025, with ell. 50eGrid Cendenser .00025, with ell.. seed 2-meg

leak 80eSPEAKERS

Eris Balloon Cirelold (torrid) 3.05Brun* COM for Roberts' Kneekeut 9.001.65

$1.451.011

75e55e

Firth SC or DC JACKS

i.e.. SC, 35e DCFederal SC. 40e: DC

FIXED CRYSTALSCarberundumRasta

DIALS

34.5013.58

50059e45s60.

1511e

45.$1.30

311440,511.

30045e50o

$1.5095e

51.451.9595050c1154

1.1025e50e

2.75

$1.45

2.252.50

51.3930e

BALLASTSVeby, % mil 50sAmperite, far all tubes 150,011$ your tab.). 954

HARD RUBBER PANELS7810 6128 7118 $007112 708 7:21

11..25

gge 7824 1.107026........91.657Fler1411126 Clued, 7124" drilled and engraved 2.65Far Pm/erten, 7:10" drilled and engraved 2.50For 3-Tabo Abassadar, drilled and engraved 1.45

MISCELLANEOUSChtrodatDub I lior 0 erstran (Rued RF traasforilisr) 2.28Cresloy Pun5.1oad Battery Cable .. .. 45.Promote A Battery Switch 12eColumbia 5. Htemsemb Coll Meant. geared 95.

.1002

Shortwave RF Cho. CellAmrad Vert...tor (env type)Fresh..B Ellleater (AC)Freshman Reetify leg AO Tube 2.00Freshman B Ellleater (DC), emds no tube . 17.10Centrelab 500.000 -ohm pet 1.85B esebeard 6%117" 25e"Brim" Brackets. per pair 1.09S lobs 45.0,11 B BM-tory. 1.851" Bezels 10ePyre: Insulator 35eCommesItIon Insulator 10.100 ft. 7 Strand Aerial 40e50 ft. No. 14 Mel. Leadln 55,Ground Clamp 106Keystone Arrester 1.10"Bruno" 13 lading Poets, dozen 40.Parent Plugs toePhone or Speaker Cords. tipped 40eEngrweings for Panel. IleTowerione Smite Shelf. !Imitate. Resistor andLeak Mount. (unit) 2.75"Bruno" 14 pt. Tap liwitsh 494$1.00 Hydreraeter 45eBustler, round or square, 3 for

12.15011S13:7kjIhr C. wiensgerth

5 -amp. Westingheuse Noiseless; with bulb.. 14.500.50 Leader Voltmeter 654Eureka D P DT Panel Sr HO 50sTowers Scientific Earphones 1.95

ErunoShort -Wave Coil. Woundwith rolled aluminumprimary and rolled coppersecondary. Strictly low -loss. Used with a .00025mid. variable condenser,it tunes from ZS to 110meters, getting bothWGY and KDKAshort-wave programs.

130CoL RADIO SERVICE CO.Dept. W New York City

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PHONOGRAPH ILLUSTRATED THE BERNARD 1 -TUBE...

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