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'fGENL _RADIO

.XPERIMNT

N 4 B 9

T Status   of  "A  Btter y 

Elimination B BE Eii

The quetio ot requenlyhead a the New Yo RadioShow, jus past was How abou Aeimiatos?" baey eliina-ors were ehibied in gea numesand may vaietes, bu o "subsiues of geeal apcatonapeaed

The pobem of lame suplyom alenaig cuen is eeay eren fo tha of plaesupy. It is ot a quesion of hepwe suplied u the voltage atwhh is uled The power reuired for a upy agesfrom 1 wat fo h dy cell ubeso 9 wats fo he 0 whie heplae powe fo hese ubes .wat ad 9 wats, respecvely Theaveae se daws a lamen load ofabou was ad a ae load opehas wats There s noteough derece eween thewatage requiemens of pae andamet o ivolve geat diculy

The essental deence betwee

the pate and lamen upples is hey voage whch s aou 100o he ae as comaed to 5 forthe ae As power was sequa to he cure suplied esthe supy voage, oughly twetytimes he curet s equed to suply a give nume of wats o lame as would e reured at helate. The grea dieece henbetween he demands of lamenad lae suples s no of owebu of curen. Plae cuesuy device ae no called on odelver moe a 5 0 milaeres,whie  e flamen ay daw tw o or 

moe apees

Drc cren power iers foalteratig n tha powe at highvolage and low cuen canno etrasered no ower at owoltage ad hgh cuet whou heuse o ahe exesive equpenI s heefore necesry o use heD. C power at the cuet andvolage uplied y the ecer

Recication and leing s generaly ecessary i oder to use aeaig ure for lamen supplyhe lat age of audo aplcaocan be un wih aeang crreno the ae wth exelle els Whe he sght hu esul-ing fom . o the lamen amie hough successive ubes,i reaches a obectonable magni-tude Ths the use o aw A. C isconed o the as tue. This sgeeraly a owe ube, and e-quies a geae ame suplyha the othes Under cerain condiions where oe hum is otojecabe, i may e possble to

oeate two sages of ado aplcaion on alrnating cuen. Thedeeo ube ust have a suy owel leed dec urrent.

The maxmum cuent avaaeom a snge tube of he kindsoualy used pla supplydeces is aout millameesThis s the curet equed by a onetue se employg a UX-99 tube. s delvered at g volage fte st s so wired tha he es arein sees any nuber (up o 0)U199 ues ay e opaedom suh a tue whe ledwth a suabe tansforme an

l s he sae un s eerally

ud or boh and B spply, woud be necessay to desgn asomes ad choes to deve hiscu a abo o n odero ae care o he ae and gridvoage o the UX-1 tue This isomewhat epenive u by omeas imposible. heosa ouciet resisace ad cue cayig caacty is also eued

It wl be seen tha A eaofor UX99 ues s easile ofa a he wie ow howeverthere is no comeca eiminaorfo this seice availabe he eldfo uch a evice would be verymie rs ecause of he com-aaiely few s ts usig 6 ilues ad seco because rewirgo the s s equired

he gof idivdual itaaos of

this

id howeve includg buidnguit ad rewiring he et sholdrove a source of odeabe roo those deaes a evice aonswho undeake i. he me ye o

insallation would no be enielybeyo'd the bouds of aclywit 0A tubes i a rece ubewee availale ulyig 5 liamees The chokes ad esitacesfor hs arrangemen would presenconsideable diculy his wouldesult in greate bulk, and maerallygreater expense tha would heequiment fo 99 tues

There ae a nume of low volage reces avalabe which ause to chge attees he out-put of these its s al o suplhe lamen cue dan an seand ey would e sable fo

geel lme uy

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    Z   

e ba n cse 1sferig. T ondr i t a evo ting - cr dg oe o and fn t dt anoh. Th lg rnt qd b e upp wd d o t

h c paiy n '

qud n paupl o pt a serous rblm Thlw vltae av hg- fyig ee a dop h y t.h s hoke hav very d I do ppr dane, and at h s odha o r e o wold eui Fraely a h -a o o dtd a · givn dg ofong e omwaEe alg for t th t co o a a w suplyto fnih 2 amp oud om ha o pt. Th d ot w mltipid gaproio ul elyi o w d.

T ost o a oa baty isf ore, y hn hat a t  wod b. hbg t tike hagb mbt wc whlot b ubt d rov i m ou fm

tng r line T chr gr s oab t re adikey t ema o ome m hot atoy gl po l Th se f U-19b s l, owve ovi e expr do t rv .

Ao tp f A li wic dy ri re a lr g " . • d >trdy

p, flt• ·n�1s

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: f k P blf dvon: )�· � i tC t - 'aus , u � l o tMS. th1ug L anode, �ch b a < F t h mo « j5 o w '

q l p·

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Wt ube hal U in My owr

Ampler?A hr to  tbs vilable fo use in the la udio  stg w

c drb pwe si red wth ft aliy, om qustin  

ren as o which of th  tubes should ud in  a  given  ce.

Th  plae haac of te b (UX1 7 I nd  X-2 I 0) or

(37 an CX1) as ws:ux

a Un<istore

Grid "

o

  _ Pla e Vol:

up IJ A (Mlwat)

16!274

908

500 10 200 33020 3

u1l

O

( U(j A lfl Gi' V P Vl H (

4

910.1873

90

135 

15 7.5 

5025

900 8

800 5 7400 90 7.5600 0 70 76000 140 77

odg r h otpt

t l a isw r h 7 f a on-dio f p oag lowoupu rstn iras theg a re om the be t per, d m· o h l anao f hi T w est

a in gat rgtransfr at ow feqees, wheldak nec

T tg wh m pd a b wout siggd too i a idaedby b t Anco t tl will show th t a g put do

2

1 4 h t wi muh 8 volts

"'maxiu n- s n 1 Y wice

t 8 t wl ;) A 4 S v ( •· l;vr smw o h s

Th mpliction fc f 2 a vlg.

F h bv pobe w r wo ub

W e va aai l a 200 e I 71 �o vrbly

i dd to b ga os o ightb he ae l lag asy m te I 0 b od s wth 4   o its p.

Te 7 be d t o

e wn dsd obta te v a ling ow diro g e 0 I u r ce. dtd utt mr a h f 0 I A. p ak i y wd or wo t a low ea oe Wn the pt i c

pw dl�·r fm

m l q 23 o r·ct1f s b u_ ot

rqd y U L A - ' q o xv t posiy " H h

C l H pt t ud 7

NOTE x l

r r S < 11 p i l} e

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  �eEXPRIMNT

he Vacuum T ub  Brid ge y HORAT W L M ON, D

he degree o pe1onnd bete sdig as we

s freedom fom oe mnortoubles may b obtanedby dng he eveal patsnto a poperly desgnedbdge nt. Suh a bdges descbed e fy ne Genera ado lletn44

e uses of he reeeectode vacum tube hae be

come so manfold hat estdy of ts vrious cha  ter-istcs is of cosdeable impotnce Sevel tueesngdeves more o ess eaboae n desgn

hve been

deveoped and placed n themaket. These ly consst o a sees o m s ndreotas wh o who enosed teries nd e desgned to chec ·lmenpower nd to mee cer-in socled "stat charactess suh as he jont

emssion to gd and pate ote stedy pae curent pass-g nde y patca condons of lament crrent ovoage plte votage and

F l. Th  YJ>  361- acum u,t Uridge Mnf 

he aachd cves egve to istate aa obtained w his bidge ponwo deen tubes. In es se mred A thegd bas was ried ove aconsdeable nge. In e

second set mred B elment voltage ws dsted at vaous e . n

DC grid bas. Fom  chaactersic 

es obtined hs manner thestatic ampaton onsnt andohe daa of aue a be deermined. Under  ceran condions,oweve he dynamc chrterists' of a e ae f e fundaent mponce. Cief amongthese e he Aplon onsant,he Plte Resstane, and te MuuCondctance, wh the rtio of

the fome to the te.The acu vaue of he Ampica

tion Constan gee wth the vaaon o this qunty wth deentamen mpetures plae vogesnd grd potenls s of amountimportance in detemnng he opeatng hactess o a pacurbe en e as a voltage ampier. he ae Res tnce s reo less deermned  by he geomeri-c constuion and te lamenemisson o the ube so tht any defect o abnormal vraton in tesefors may ready b deeted by

m a•uring hs picur dynmconsant Knowe f he aonutnce o a te s mportantin deemnng ts bevor as apoe amper and as n oscator

To obain such ta s neessayto ppy an aud feeny tonesoure preerably nusodal n chracer, to the grd te be and omae use o ceran bancedbdgemeasurements hree ccits fmeasuing hese tbe consnts aeown on page 203 of Vn der iset book "T hemonc uumube ede e g baees

y Gn Rd C

and ament rrent conols eseccuits reuie two decade resstanceboxes hree xe esstances o 1 00 nd I 0 respectvey atone source and a pa o eleponesFor auate measemens i been fond beneca to add a smalvariocouple o noduce an indcve pn between he esoce nd e pones n order ocounteract e eect of apay be

tween he be eemensTe crcus ay be se p ihndvdul peces of appaus b a

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eiher c e e plte enIp e amplaon con-

sn Mu te pte ressnce Rpan the mutal condtane gmwere measued dety on hebdge

Referng to ge A we see tthe emsson s pctcly c tsxteen vols negave on he gde no sgn of saturaon s eachedt sixteen vos positve. e amplcaon consant emans esenay

he me om to about 9 volnegative, and hen lls o s epate rent beomes anomo Wth n ncr gy posvegrd the vae of M s awayrpdy

Wth a stong negatve bs hepate resstane o ou e gh,but  hs f rapdly and bomes e-sentaly onstant o postve v uesof grid . voltage On  the  oth   h nd,

the utal condanc rs rpdlys  the negatve  bs  s educed ndatns n ppoxmtey unfom

vlue the gd poive.

Fiue  B  shows  tt  th  plate  r-rent  rises wh e fnt tempea-e echng  stuatio    abou te

ed  men  votag of he te.Te mplcton  onstan  s a  maxi-

mum at  the owest workabe lament 

temperature  nd fals o  oe  o 

les nfomy as  Ef  i nceased Thplae resistance  emns onsan

down to 4.S  olts and Qn rises h

nceing  apdiy  s he  lmen is

cooed. The  mut condtne

urve,  of  ouse exhbis a epro-

ca cha esti.

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·For Al Ppua Mes

nd Cict�radio recivngsl

Type 45 Plte Suppy 

I?RO,.ED qalty o eepion, ee m

axet causd b staily eerratg "battees is w  possib hru  the use f Gera Rah Pa pp.

hs u perates on 10 l  ( 6 ce) C.and vdes laes f 45 9 30 and 20

Vltaes a eadil aaptable o all parmakes and ccuits f ao revrs  by mans  fxed esances  hic  ae tihty sea frmu �d moisre us elminaing othesomead nisy ednces varabe resstane ltagecontrols. The un  s otaind n  a meta  as 

with attracive black  cysallne fnsh, and has  acnel cate sicie ith BH atheon Te·-···6.

ype Power Ampi-fer and Pe Supy

THE pe s sma h abe desbeni ept hat it has dtina aur

o a e Amplie an ses the X-13 or

CX1 e e as a ecier sea ofhe aheonA er amplie i cojucio th h ae

up ts net us of a te h as audo se e ades of het terive a be pat by d ell o taea ubet n cn of he oee be spple b .C fo the snday t er rsrm e poer ercms e tndny tard b o eadigad ems he s mo use f <listi dseaker prain

The plae supy p is aes of 45 an9 r he cr ad l 0 dec o ube U X37) ohe wt thep bia f this bc ihu s····$6

GEN RL DIO OMPNY, ambrdg s

GENL R  A DIO INS RUM

znd the Pals of r Bui S