rTECHNICAL MANUAL 1

No. 11-688 )

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TM 11-688

DEPARTMENT OF THE ARMYWASHINGTON25, D. C., 24 June 1955

DIRECTION FINDER SET AN/TRD-4A

1. INTRODUCTIOK

I. General____________________________________________II. I;escription and data_h__nh hhUUn_hh__

2. INSTALLATION

I. f1ervice upon receipt of Direction FinderSet AN /TRD-4A_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ __

II. Initial adjustment of equipment Uh__U n_h

3. OPERATION

I. Controls and instruments nh_uun_n_h_______II. Operationunderusualconditions_huu_u_u___u__u

III. Operation under unusual conditions_ ___________________

4. ORGANIZATIONAL MAINTENANCE

I. Organizational tools and equipmenL _ h n _ _ n u u U U__

II. Preventive maintenance_ __U_ _n_ n __________ ________

III. Lubrication and weatherproofing_ ___ __ ___________ _____IV. Troubleshooting at organizationalleveLnu_n_nn__n

5.I.

II.III.IV.V.

THEORY

31-43

44-51

52-6061-8283-86

87,8889-9293-95

96-103

104-110111-114115-124125-127

168, 169

170-176177-182

183, 184

:::=ection V. Troubleshooting in Radio Frequency AmplifierAM-496/TRD-4_ ___u __ __ _n _ nn _n_ _ _ _ h _ U h _ _ 185-190 169

VI. Troubleshooting in Junction Box J-95B/CRD-2 and

Switch Box SA-345/U h __h _ h ____ _____u ___ __u u 191-194 171

VII. Troubleshooting in Radio Transmitter T -279 fUR h u ___ 195-19D 173

VIII. Repairs_ n n _____ ___u _ __n n n n_ _______ u _____ __ _ 200-213 176

IX. Alinement procedures_ ____U U U __ _____________n ____ 214-222 184

X. Final testingh__uu__nnnn_uhhu u 223-232 191

7. SHIPMENT AND LIMITED STORAGE ANDDEMOLITION TO PREVENT ENEMY USE

CHAPTER

Section

J

tI

Fundamental principlesn _ u _ _ _ _ h _ __ _ u _ u u _ n _ _ _ n

Block diagrams_ _ _ _ _ _ _ _ n _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

Theory of antenna systemsnhh__n__nun__nnn_

Theory of Goniometer Drive MX-1170/GRDuu_un__Theory of Electrical Goniometers

GO-5/GRD and GO-6/GRDu__m_u nnu_ 128-132

Theory of Radio Receiver R-390 /URR_ u ___n _n __n _ 133, 134Theory of Azimuth Indicator IP-137/GRD__u_u__n__ 135-148Theory of Radio Frequency Amplifier AM-496/TRD-4_ _ 149-156Theory of power and control circuitsn _ h _ u u _ _ _ u u __ 157-162

Theory of Radio Transmitter T-279/UR_uh__n_nn_ 163-167

VI.VII.

VIII.IX.X.

6. FIELD MAINTENANCE

I. Troubleshooting at field maintenance leveL u _ n n _ n _ n

II. Troubleshooting in Goniometer Drive MX-1170/GRDand Electrical Goniometers GO-5/GRD and GO-6/GRD

III. Troubleshooting in Azimuth Indicator IP-137/GRD_u__IV. Troubleshooting in Radio Receiver R-390/URR_ _______

I. Shipment and limited storageu h _____n _________u ___ 233-236

II. Demolition of materiel to prevent enemy use_ n n _n _u _ 237,238

INDEx 208

3652

576680

81818586

96100106116

117120123143147150

156

157159168

197198

1

Paragraphs Page

1,2 33-30 3

CHAPTER 1

INTRODUCTION

Section I. GENERAL

b. DA Form 468, Unsatisfactory EquipmentReport, will be filled out and forwarded to theOffice of the Chief Signal Officer, as prescribedin SR 700-45-5.

c. DD Form 535, Unsatisfactory Report, willbe filled out and forwarded to CommandingGeneral, Air Materiel Command, Wright-Pat-terson Air Force Base, Dayton, Ohio as pre-scribed in SR 700-45-5 and AF TO 00-35D-54.

d. DA Form 11-238, Operator First EchelonMaintenance Check List for Sig~al CorpsEquipment (Radio Communication, DirectionFinding, Carrier, Radar) will be prepared in

The following forms will be used for re- accordance with instructions on the back of the\)orting unsatisfacbry conditions of Army form (fig. 51).equipmentand in performing preventive main- e. DA Form 11-239, Second and Third Eche-tenance: Ion Maintenance Check List for Signal Corps

a. DD Form 6, Report of Damaged or Im- Equipment (Radio Communication, Directionproper Shipment, will be filled out and for- Finding, Carrier, Radar) will be prepared inwardedas prescribed in SR 745-45-5 (Army) ; accordance with instructions on the back ofNavyShipping Guide, Article 1850-4 (Navy);, the form (fig. 52).andAFR 71-4 (Air Force). ... f. Use other forms and records as authorized.

1. Scopea. This manual contains instructions for the

installation,operation, maintenance, and repairof Direction Finder Set AN /TRD-4A. A typi-calinstallation using Direction Finder Set AN /TRD-4A is shown in figure 1.

b. Forward comments on this publication toCommandingOfficer, The Signal Corps Publi-cationsAgency, Fort Monmouth, N. J., Attn:StandardsDivision.

2. Formsand Records

Section II. DESCRIPTIONAND DATA

3. Purpose and Usea. Direction Finder Set AN /TRD-4A is a

completetransportable radio direction findingstationthat covers the frequency range of .54to 30megacycles(mc), with separate facilitiesfor direction finding, intercept reception, com-municationreception, field telephone communi-cation, and frequency measurement. Thesefacilities are housed in Shelter S-44A/G andarearrangedaround three individual operatingpositions,one each for a direction finder, inter-cept, and communication operator. Special

tools, test instruments, and field spares arepacked in bins and chests within the shelter.In addition, bins, brackets, straps, and racksare provided for transit stowing within theshelter of all components of Direction FinderSet AN /TRD-4A except the power units.

b. Flexibility to meet widely varying fieldconditions is pr:Jvided by three direction find-ing antenna systems and two basic bearingindication methods.

c. The direction finding antenna systems area fixed-position, four-element Adcock antenna

3

l

)

1. SC4

a. Tlinstallaof Dimcal instlTRD-4,

b. FoComma]cationsStandar

2. For

The 1portingequipmetenance :

a. DDproper 1warded ~Navy Shand AFI

3. PurFa. Din

completestation tlto 30 me!Jfor directmunicati(]

TM688-S2' cation, afacilitiesare arran:positions,cept, and

Figure 1. Direction Finder Set AN/TRD-4A.

2

with a wire-mesh counterpoise, a fixed-position,crossed-loop antenna, and a manually rotatablesingle-loop antenna with a high-sensitivity pre-amplifier.

d. The Adcock antenna is intended for fixedstation or semifixed station direction finding oneither ground waves or sky waves from nearbyor distant transmitters. Both of the loop an-tenna systems are usable for either mobile,fixed station, or semifixed station direction find-ing, but only on ground waves received fromrelatively nearby transmitters.

e. The rotatable single loop and preamplifiercombination is intended for weak-signal ground-wave applications that require high receivingsensitivity.

f. The types of indication are automaticvisual (using a cathode-ray tube (crt) indica-tor) and aural-null. The visual indicator isalways used with a motor-driven goniometer.Either a manually operated goniometer or therotatable single loop is used for aural-nullindication.

g. Automatic visual indication has the gen-eral advantages of high-operating speed andconvenience, accuracy on swinging bearings,positive sensing under all conditions and is, inaddition, more suitable for use by unskilledoperators.

h. Aural-null indication is provided prima-rily because of its advantages under conditionsof noisy reception and cochannel interferencefrom other stations and also for standby useif the visual indicator should breakdown. Thesharpest receiver selectivity may be used withaural-null indication to minimize noise andinterference. Separate and accurate bearingscan be obtained on several interfering trans-mitters by using aural-null indication in com-bination with the receiver beat-frequencyoscillator (bfo). The disadvantages of aural-null indication are less definite sensing, slownessand reading difficulty when bearings are swing-ing, and the requirement for greater operatorskill.

i. Direction Finder Set AN /TRD-4A re-quires a single-phase 50 to 69 cycles per second(cps), alternating-current (ac) power sourceof 2,000-watt minimum capacity and a nominalvoltage of either 115 or 230 volts. The powersource must be well-regulated and its outputmust be free from transient fluctuations. Powersupplied to the electronic components of Direc-

4

tion Finder Set AN /TRD-4A is passed throughan autotransformer located in Junction BoxJ-95B/CRD-2. Provisions for metering linefrequency and voltage and for adjusting theline voltage to the optimum operating level of115 volts are contained in the junction box.

j. Two Gasoline Engine Generator Sets PU-236/G, which consist of a Power Unit PU-58/Gin Trailer M-105, are supplied with each Direc-tion Finder Set AN/TRD-4A. A power unitselector switch (in Switch Box SA-345/U) issupplied. This switch has three positions, twofor the power units supplied with the set andone for a third power unit or an outside powerline.

4. Systems applicationa. One direction finder set can determine

only the bearing of a distant transmitter. Twoor more direction finder sets must be used tofind the position or fix of a transmitter by tri-angulation (par. 6). Single direction findersets are sometimes used for homing of aircraft,but are commonly, direction finder sets, such asDirection Finder Sets AN /TRD-4A, are oper-ated in groups or nets, and bearings from theindividual direction finder sets are plotted onmaps to establish the fix of a transmitter.Direction finder nets usually use a minimumof three sets. Figure 2 illustrates the use ofthree direction finder sets to determine the fixarea of one transmitter and for intercept moni-toring of a second transmitter.

b. If direction finding could be accomplishedwithout errors, a fix would always be a definitepoint. However, because of small and unavoid-able bearing errors and fluctuations caused byinstrumental and propagation factors, a prac-tical fix almost always is an area within whichthe signal source (transmitter) exists. The twobearing lines drawn toward the source fromeach direction finder in figure 2 represent therange of possible error or uncertainty in indi-vidual bearings.

c. Figures 56, 57, and 58 are simplified func-tional block diagrams of Direction Finder SetAN/TRD-4A, which show the relationships ofthe various components to each other. Direc-tion Finder Set AN/TRD-4A is an extremelyversatile direction finding system and the com-ponents in this set may be interconnected inany of several different ways to produce opti-mum performance in all circumstances.

FIX AREISIGNAL SO

NO.1

1..~

RANGEOFBEARING UNCERT

OIRECTIONFINDING

DIRECTION FINDERAN/TRD-4A

Figl

5. Basic P

A line per]front alway!tenna. A diwave front.is then assumfront. For dEgraphs 104 n

6. DefinitiolThis paragl

the technicalAmbiguity.

either of two IAzimuth. (:Base line. .

tions of two d.Bearing. Tl

mitter measurdirection such~

Direction. T;are arriving f

!>ughBoxline

r thereI ofox.Pu-

-58/GDirec-r unit'U) iss, twoat andpower

erminer. Twoused toby tri-

I finderLircraft,such as

re oper-:rom theotted onlsmitter.ninimum,e use ofle the fix~ptmoni-

)mplisheda definite!unavoid-caused bys, a prac-.hin whichI. The twource fromIresent thety in indi-

,lifiedfunc-Finder Set,ionships ofher. Direc-1 extremelynd the com.onnected inroduce opti-mces.

----- ~-~

--.~-~-_.

.-

.

INTERCEPTION

- DIRECTION FINDER

SET ; , TRD-4A

Figure 2. Tactical use of direction finder sets in a net for position finding and interception.

5. Basic PrinciplesA line perpendicular to an undistorted wave

front always intersects the transmitter an-tenna. A direction finder set first locates awave front. The direction of the transmitteris then assumed to be perpendicular to the wavefront. For detailed information, refer to para-graphs 104 through 110.

6. Definitions

This paragraph contains an explanation ofthe technical terms used in this manual.

Ambiguity. Capable of being understood ineither of two possible directions.

Azimuth. (See Bearing.)Base line. A line passing through the posi-

tions of two direction finder sets.Bearing. The direction to a distant trans-

mitter measured clockwise from a referencedirection such as true north or magnetic north.

Direction. The course on which radio wavesare arriving from ,a transmitter.

Direct bearing. The bearing from the direc-tion finder set to the transmitter.

Error, instrumental. Errors in the bearing,indicated by a direction finder set, which arecaused by equipment inaccuracies.

Error, polarization., Errors in the bearingmdicated by a direction finder set, introducedby horizontally polarized components of theelectrical field under certain transmission con-ditions. Originally called night effects becauseerrors are generally greatest at night.

Error, propagation. Errors that arise inpropagation because the waves do not travelover a great-circle path.

Error, site. Errors caused by irregularitiesof, and obstacles or reflectors on, the terrainaround a direction finder set.

Fix. The position of a distant transmitter.May be obtained by triangulation plotting ofthe bearings from two or more direction findersets.

5

Fix area. The area within which the signaloriginates (fig. 2 and par. 4b).

Great-circle path. The shortest distance be-tween two points, measured on the surface ofa globe.

Ground wave A radio wave propagated overthe surface of the earth.

Magnetic declination. The angle betweentrue north and the direction indicated by amagnetic compass. This angle varies for dif-ferent locations on the earth. It is necessary,therefore, to use charts or maps that show dec-lination and the annual change in declination.

Magnetic north. The direction toward whicha compass needle points.

Reciprocal bearing. A bearing 1800 removedfrom the direct bearing.

Sense indication or pattern. An aural indica-tion or visual pattern which can be interpretedto distinguish between direct and reciprocalbearings.

Sense signal. A radio signal added to theoutput of a bidirectional antenna to distinguishbetween direct and reciprocal bearings.

Sensing. The procedure that uses the sensefinder portion of a direction finder set to dis-tinguish between direct and reciprocal bearings.

Sky wave. A radio wave that is propagatedby reflection from the ionosphere. Sometimescalled an ionospheric wave.

Triangulation. Determination of the positionor fix of a distant transmitter by plotting bear-ings from two or more direction finder sets aknown distance apart.

True north. The direction to the geographicnorth pole.

7. Technical Characteristicsa. Direction Finding Components.

Frequency range__ __ _h _0.54 to 30 mc.Antenna systems:

FixedAdcockantenna__Four vertically polarizedmonopoles.

Two diamond-shaped loops.Fixed crossed-loopantenna.

Rotatable single-loopantenna.Phantom sense

antenna.

Part of crossed-loop (One dia-mond-shaped loop).

A portion of the voltage fromeach monopole in the Adcockor from each leg in thecrossed-loop provide3 sensevoltage when using eitherthe Adcock or crossed-loopanteI1na.

6

Vertical sense antenna.._A vertically polarized monopoleprovides sense voltage whenthe single-loop antenna isused.

Types of signals on which Amplitude-modulated, contin-bearings are obtained. uous-wave, or code, and fre-

quency-modulated.Bearing indications:

Instantaneous visuaL __Bearing pattern, propeller (A,fig. 3); sense pattern, foldedpropeller (B, fig. 3).

Aural-nulL __..___h ___J'\ull in the loudspeaker output.Accuracy:

Instrumental accuracy _Errors do not exceed 2° forvertically polarized waves.

Octantal error _________Varies with the frequency,direction of signal arrival,and antenna installation (fig,50).

X umber of tubes:Df receiver __ __ ___.. ___33.

Azimuth indicator _____10.

Rf amplifier ____ _____ _3.

b. Communication and Intercept Receivers.Frequency range_uu___0.5 to 32 mc.Antennas ___U h ____Vertically polarized whips.Types of signals received_Am, cw, and fm. Narrow-band

fm can be monitored by de-tuning; wide-band fm can bemonitored, but voices will bebadly distorted.

Sensitivity_h__hh Am signals, 3 uv; cw signals,1 uv.

Number of tubes uh33 in each receiver.

c. Radio Transmitter.

Frequency range_ _______0.50 to 30 mc.Antenna__ __ __U h _n ___Telescopic, vertically polarized

whip.

Transmitter type_ __ ___ __Master oscillator power ampli-fier (mopa).

Types of signals___u___ _Cw and am (mcw).Effective rangeu u _h u _Le3s than 1 mile.

Modulation circuitu_ __hNegative resistance oscillator.

Weight__n_h_nnnh_19 lb. (with batteries), 8 lb.(without batteries).

d. Power Input Requirements.115/230 volts, 50 to 60 cps:

Three radio receivers 510 watts.(170 watts each withthe oven heaters off).

Rf amplifier__ u u _ _ u18 watts.

Azimuth indicator __u _100 watts.Goniometer drive_n__ _125 watts.Heater n 550 watts.Ventilation blower 300 watts.

motor.

Lighting (four 60-watt 240 watts.lamps).

TotaL _ _ _ _ _ _ _ _ _ _ _1 ,843 watts.

Battery powe:transmitter

Battery BJ135-volt.

Battery BA1.5-volt.

8. NomencllThroughout

be referred tocommon name

N omenclatl

Direction Fin(

AN /TRD-JGoniometer D

MX-1170/<Electrical Gon

G0-5/GRI:Electrical Gon

G0--6/GRDAzimuth Indi<

IP-137/GRRadio Transm

T-279/UR.Radio Frequel

fier AM-49(

CounterpoiseMX-1169/C

Radio FrequeJm~sion L

SA-346/GR

TY

\. :~...

. .'.,:,,'

>pole.vhen

.a is

Battery power for radiotransmitter:Battery BA-424jU,

135-volt.67.5 volts, 4 ma max.90.0 volts, 20 ma max.135.0 volts, 20 ma max.1.5 volts, 350 ma max.

ntin-I fre- Battery BA-404jU,

1.5-volt.

r (A,>lded

8. Nomenclature AssignmentsThroughout this manual a component may

bereferred to either by its nomenclature or itscommonname as follows:

tput.

, fores.~ncy,rival,I (fig,

Nomenclature Common name

Direction finder set.

gnals ,

Direction Finder SetANjTRD-4A.

Goniometer DriveMX-1l70jGRD.

Electrical GoniometerGO-5jGRD.

Electrical GoniometerG0-6jGRD.

Azimuth IndicatorIP-137 jGRD.

Radio TransmitterT-279jUR.

Radio Frequency Ampli- Rf amplifier.fier AM-496jTRD-4.

CounterpoiseMX-1169jGRD.

Radio Frequency Trans- Rf switch.mi~ion Line Switch

SA-346jGRD.

Goniometer drive.

Signal goniometer or indicatorgoniometer.

Signal goniometer.

Azimuth indicator.

Radio transmitter.

I..band

'y de-an be,ill be

Counterpoise.

uized

Lmpli-

ator.8 lb.

TYPICAL BEARING PATTERN

Nomenclature Common name

Df receiver, intercept receiver,or communication receiver.

Adcock antenna.

Radio ReceiverR-390/URR.

Antenna A8-533jGR(group of four).

AntennaAT-297 jTRD-4 Crossed-loop antenna.Switch Box SA-345jU ___S\vitch box.Junction Box Junction box.

J-95B jCRL' -2.Electrical Equipment

Cabinet CY-1426jU.Shelter S-44AjG ________Shelter.Cable Payout Reel Cable payout reel.

RL-174jG.Gasoline Engine Gener- Generator set.

ator Set I U-236jG.

Electrical equipment cabinet.

9. Packaging Data(fig. 4)

Direction Finder Set AN/TRD-4A, exceptfor the generator sets, is shipped with the com-ponents mounted in Shelter S-44A/G. Theentire shelter is contained in one packing case.

Dimensions(in.)

Volume(cu. ft.)

Weight(lb)

(including crate)Contents

147 x 84 X 87 622 7,000 (3,200crate).

Refer to table

of compo-nents (par.10).

TYPICAL SENSE PATTERN

Figure 3. Typical bearing and sense patterns.

---

.MOISTURE -VAPORPROOF BARRIER

10. Table

Com

PADDEDANTENNABRACKETS

HOLD DOWN BAR

INNER SHROUD-HEAVY FLEXIBLECORRUGATED PAPER

Tripod head ada,

Tube socket adarAntenna AT-297

loop).Antenna Assemhl

(Adcock) contaAntenna Se~1

AT-442,AT-4431AT-4441AT-4451

Antenna Bas

Antenna COU]Ground strapAn tenna 1031

Disk 1'.1JAntennaGuy adaGuy Stall\'ylon glLocating

Whip antenna conMast Base AIMast Base BI

Mast Sections:MS-1l6-Au.MS-1l7-A__.

MS-llS-A___

SKID MOUNTINGGASKETS

Canvas bag (contaand locating pin

Ball and socket joiTripod (for compa

TM688-70

Cable Assembly S€CG-I097/TRD-through WI04).to signal goniom

Cable Assembly SeCG-I098/TRD-through W204).signal goniomete

Radio FrequencyCG-1078/U (2through W404).ometer to azimut

Radio Frequency ,CG-1079/V (2 ftAzimuth indicatgoniometer.

Radio Frequency ICG-1079/U(8 ftRf amplifier to rf

Radio Frequency (CG-1079/U (2 itnal goniometer to

SEALI NG GASKETS

OUTER SHROUD-HEAVY FLEXIBLECORRUGATED PAPER

BOLT

NOTE:

EXPORT ROOF SHOWN.

FOR DOMESTIC SHIPMENTUSE SINGLE SHEATHING.

CRATE BASE

Figure 4. Packing shelter for export shipment.

8

I'-.: ~.

10. Table of Components

Component

Tripod head adapter __ _ __ __ __ _ __ h

Tube socket adapter ______________Antenna AT-297/TRD-4 (crossed

loop).Antenna Assemhly AS-533/GR

(Adcock) contains:Antenna Sections:

AT-442/GR_ ____________AT-443/GR_ ____________AT-444/GR_ _ _ _ _ _ _ _ __n_

AT-445/GR__h_ _ h

Antenna Base MT-865/GR____Antenna coupler _ _ _ _ _ _ _ _ _ n _ __

Ground strapn _____h n ___hAntenna Loading:

Disk MX-1168/GR__ _____Antenna mast container ___

Guy adapter h h __ _______

Guy Stake GP-2_________Nylon guy n_._n____Locating pinsh _ _ _ __ _ _ ___

Whipantenna contains:Mast Base AB-15/GR_h_____Mast Base Bracket MP-50 ____

Mast Sections:M8-116-A___________________M8-117-A___________________

4 & I spare 1%1

1%4 & I sparenn_ nh 304 & 6 spareS_h_ %20 & 5 sparesn_ n________12 & 3 spares_ n

ln________

5 & 10 spares___ nnn__h22h _ n -- _nnn inh __n_ -

I

nn- -- h _

I

n _ -- _n_ _

1 _ ~~~ _i~~ _ _I~ ~~ ~~ ~~ ~~~2__n nn__ __h__nn n__ h_ _

Reqd No.per unit

Height(in.)

Width(in.)

L__n n__

I

I~3n I~Ln_hn 54~

4~dia.I dia.54~

4 &I sparenn_l_h_h ' 2dia.

4 & I spare 'h_nn___4 & I sparen _n'h ___n h_4 & I sparenh_'_h h_4 & I spare n__h

4 & I spare 7~4 & I spare_n__ 7~4 & 6 spares_ _ h _ h _ nnn

I~ dia.IJ{6 dia.% dia.%dia.24

1% dia.IJ{6

Depth(in.)

Length Volume(cu. ft.)

Weight(lh.) ea.

--- ---1--- 1___ __ I~~oz.10~

___ __ _____1_ __ ___._ ___ ___ ___

nnnn__' 54~ in. ----------

---------- 375 in.

---------- 100 in.100 in.100 in.75 m. ----------

---------- 1776421~~~

---------- ----------

---------- ----------

----------

24 1-_____----

- __ - - - - - --1- __ __ ____ _1___ __ _____

u_ 27 in. ----------

---------- 66 in.120 in.

2% in.16 in.36 ft.10 in.

----------

---------- ----------

t__________

I~ dia.%;dia.%dia.

2 & I spare___ __'n ______n

2 & I spare_n__, n__%dia.IJ-32to ~

dia.~ to VB

dia.10 dia.

M8-U8-A_ _h __nn n n n _ nl 2 & I spare_ nn'n_ __ n h_

Canvas bag (contains guy assemblyand locating pin).

Ball and socket join L _ n n n _ n n _

Tripod (for compass)n___nn___n

ENT~G.

Cable Assembly SetCG-IO!!7/TRD-4 (170 ft.) (WIOIthrough WI04). Adcock antennato signal goniometer. a

Cable Assembly SetCG-I098/TRD-4 (9 ft.) (W201through W204). Rf amplifier tosignal goniometer.a

Radio Frequency Cable AssemblyCG-I078/U (2Yz ft.) (W401through W404). Indicator goni-ometer to azimuth indicator.

Radio Frequency Cable AssemblyCG-I079/U (2 ft. 10 in.) (W405).Azimuth indicator to indicatorgoniometer.

Radio Frequency Cable AssemblyCG-I079/U (8 ft. 6 in.) (W205).Rf amplifier to .rf switch.

Radio Frequency Cable AssemblyCG-1079/U (2 ft.) (W501). Sig-nal goniometer to rf switch. .

M688.70

2______________.__________

L _h _ __ n _nn l__ _ __ __ -n l% ~ia.L h ______n ___ ____n __h 5 dla.

2 & 2 spares__ nl_ h __ __ __-' .420 dia.

2 & I sparen__-'n__hn_-' .420 dia.

4_ n _nnnn _-'_ n _n _n -' .420 dia.

----------

---------- ----------

---------- ----------

---------- ----------

---------- 39~in.38% in. ----------

n ' %%.. ---------

---------- 39% in. n~n_1 VB

---------- 15 in. n__n_h_' %

---------- 3~in.58 in.

(max.)170 ft. __n_n_n' 68

----------

---------- ----------

----------

nhh ' 9 ft. I _n_nn__. 4

n ' 2~ ft. nnn' ~

L _ __ _ __ _ _ __ _ nln h n _ _ _ -' .405 dia. 1__ __ h n _ -' 34 in. ___n %

L___n I_h 1.405dia. Ih ' 8~ ft.

1& 1 spare___nlh__n___J .405 dia.

_n 1 3

__ _ _ _ _ _ n _,2ft. _n' ~-------

.10

Com

Coun terpoiseJ).

Canvas bag Iclamps).

Goniometer DrivEElectrical GonionElectrical Gonion

Whip antenna gu:Hand hammer ___Headset________Headset cord __uAzimuth IndicatoJunction Box J-91Telegraph Key J-Desk lamp______.Rod leveL _h____Steel tape__ _____Layout template (Loudspeaker LS-ICable Payout ReePlumb bob (for trRadio Frequency.

AM-496/TRD-Radio Receiver R

mounted.Radio Receiver R.

Case CY -979 /UIGasolme Engine GE

PU-236/G, cont~Power Unit PITrailer M -105.

Shelter S--44A/G:_.Blackout curtaBlower assembl

Fire extinguishFuel tank unit.Heater assemblHold-down bar:Hold-down barJoining cover __Folding ladder_Loading skids_.Skid rope, 1%-iTechnical manu

Panel door key.Screwdnver ___.Wrench, % incl

Antenna mast strapCounterpoise strap ~Ladder strap and buLamp tie-down straIGround rod strap___Power cable straph'Switch Box SA-345/Radio Frequency Trs

Switch SA-346/GIInstrument table_noTelephone EE-8-B_.Telephone bracket__Radio Transmitter T.A set. consists of t,

Note.-Thls list Isof spare parts. Addlt

Reqd No. Height Width Depth Length Volume WeightComponent per unit (in.) (in.) (in.) (cu. ft.) (b1.)ea.

Radio Frequency Cable Assembly 1___________h_ ---------- .405 dia. ---------- 41 in. ---------- 1%CG-I079/U (3 ft. 5 in.) (W304A).Rf switch to df receiver.

Cord CG-409E/U (2 ft. 3 in.) L__________h_ ---------- .420 dia. ---------- 27 in. ---------- KG(W303A). Df receivcr to azimuthindicator.

Electrical Power Cable Assembly I__hh______h ---------- .310 dia. ----------27 in. ----------CX-2377/U (2 ft. 3 in.) (W302).Df receiver to azimuth indicatorspeaker.

Electrical Power Cable Assembly 1 & 1 spare__ _h ---------- .310 dia. ---------- 3 ft. ---------- %CX-2378/U (3 ft.) (W301).Azimuth indicator to sigltalgoniometer.

Electric",l Power Cable Assemhly L___h__h____---------- .340 dia. ----------30 in. ---------- %CX-2379/U (2 ft. 6 in.) (W701).Azimuth indicator to goniometerdrive.

Electr.ical Power Cahle Assembly 3 & 1 spare_____ ---------- .640 dia. ---------.- 20 ft. ---------- GCX-2380/U (20 ft.) (W801through W803). Three powerunits to switch box.

Electrical Power Cable Assembly L_h__________ ---------- .640 dia. ---------- 125 ft. ---------- 30CX-2380/U (125 ft.) (W804).Switch box to terminal box.

Electrical Power Cable Assemblx 1________.____h ---------- .5-10 ---------- 8ft. ---------- IffCX-2381/U (8 ft.) (W901). Junc-tion box to azimuth indicator.

Iectrical Po" er Cable Assembly Lh___________ ---------- .540 dia. ---------- 10 ft. ---------- 1%CX-2381/U (10 ft.) (W902).Azimuth indicator to rf amplifier.

lectrical Po" er Cable Assembly L__h_________ ----------.540 dia. ---------- 10 ft. ---..------ 1%CX-2382/C (10 ft.) (W903).Junction Lox to convenienceout!et.

lectrical POI' er Cable Assembly 1______________ ---------- .540 dia. ---------- 16 ft. _______h_ 2CX-2383/1. (16 ft.) (WI001).Te"minaJ Lox to junction box.

Jectrjcal Power Cable As!'embly L_____h______ ---------- .540 dia. ---------.. 40 in. ---------- ;!4CX-2383/L (3 ft. 4 in.) (WlO02).Te"minn.11 ox to circuit breaker.

]etJ"('fi.) T',) e:- Cable Assembly 1________h____ ---------- .310 dia. ---------- 9 ft. ---------- %CX-238 ill (\I ft.) (WI003).Commun;('ation rereiver to loud-sfeaJ.e".

'\adio ].Ieqt ency Cable Assembly 2______h______ ---------- .420 dia. ----------14% ft. ---------- 3%CG-1379/L (14 ft. 6 in. each)(WI007A and WI008A). Whipantennas to intercept and com-munication reteivers.

lectrical Equipment Cabinet L_____________ 33 20 21 ---------- 8% 55CY-1426/l;.

'torae cabinet on shelter walL ____ L_____________ 32 12 30 ---------- 6% 88)perator chair _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ 3h____________ 32 18 19% ---------- ---------- 90\1agnetic compass and case_ _______ L_____________ 4 4% ;!4 ---------- ---------- 1%::ontainer for guy stakes_______h__ 2_____ _________ ---------- 29% ---------- 24 in. ----..----- ;!4::ontainer for locating pins_________ Lh__h_______ ---------- 14% ---------- 15 in. ---------- ;!4::ontainer for counterpoise______ ___ L___________h ---------- 65 ---------- 164 in. ---------- 10::ounterpoise MX-1169/GRD

contains: L_____________ 75 ft. 75 ft. ---------- ---------- 268Ground rod_ ___________ ______ 5______________ ---------- % dia. ---------- 72 in. ---------- 3

Weight(bl.)ea. Component

%

Counterpoise clamp (invertedJ).

Canvas bag (counterpoiseclamps).

Goniometer Drive MX-1170/GRD.Electrical Goniometer GO-5/GRD.Electrical Goniometer GO-6/GRD.Whip antenna guy________________Handhanuner____________________Headset_________________________Headset cord_ _n n_ ______________Azimuth Indicator I P-137 /GRD ___Junction Box J-95B/CRD-2___uuTelegraph Key J-47 ______________Desklamp_n__n __n__n _u_ ____Rod leveL ___ u ____n__

Steeltape_______________________Layout template chain (antenna) u_Loudspeaker LS-166/U ________- -_Cable Payout Reel RL-174/Gnn__Plumb bob (for tripod)____________Radio Frequency Amplifier

AM-496/TRD-4.Radio Receiver R-390/URR, rack

mounted.Radio Receiver R-390/URR with

Case CY-979/URR.Gasolme Engine Generator Set

PU-236/G, contains:Power Unit PU-58/G_________Trailer M-105 n _____

Shelter8-44A/G:__nn_n _u_Blackout curtain_ __- - _ - - - - ---

Blowerassembly u___u_Fire extinguisher __ ___ - - - - u u _Fuel tank unit__ __ _ __ _- __ - ---

Heater assembly______________Hold-down bars_ ___ _____ _-- --

Hold-down bar extensionsn____

Joining cover __ __ __ ___Folding ladder __ ____ __ _- _--__

J,oading skids_ _____ ______ __ __Skid rope, 1%-inch_ __ _ __ _ ____

TechnicalmanuaLn __ _ u _ _ _ __

Panel door key _ _ __ __ _ _ _ _ __ _ _ _

ScrewdrIVer_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __

Wrench, % inch u___n___Antenna mast strap assembly ___. __Counterpoise strap assembly _ _ _ _ _ __

Ladder strap and buckle assembly __

Lamp tie-down strap assembly ___ __

Ground rod strap__ _'__n ____u ____Power cable strap_ n _U __ _________

Switch Box SA-345/U ___ _ __ __ ____

Radio Frequency Transmission LineSwitch SA-346/GRD.

Instrument table__ ___ ___ __ __ _____

Telephone EE-8-B_______________

Telephone bracket_ __ ___ __ ___ ___ __Radio Transmitter T-279/UR n

6

30

2

. ~

55

88901%~~10

2683

L 10% 12% 192m_m_u 5% 4% 8%Lmm 5% 4% 8%2 _ n n . __ ____ __ u __ ______ ~{6dia. n ____ ___ _L__nn_u u_C n u_ __ '__u_n___3_n_n 3 6 'nu_____.3_nn uh uu__ uU_n__ __u_un_L u_u_ 10% 17 191uu 147'2 15 14L nn___ 1% 27'2 57:1:2uu__u__n__ 32 37'2 5Lu n__n 4 % L_u____1u n_ _nn '_hnn__

~~~~~~~~~~~~~~~-4mnu~ -2~--unl

-4u ,

Luu 26 24 19

Lummnm 1% 1% dia.

I

-u-----L__mmn___ 33% 6% 6%

Lnm m.l ]0%

2mm_nnml 12~

2____________..

---------- 1.48.]2.12

--------------------120 in. n____16 in. __h______7 in. __________75 in. n_

n 1.90

_ __ n __ _u 1.76

---1----------- -1 _____

620 in.16% ft. _uuu___, %

275%88

404%4%.131%6564%2%

82%

87%

1,5862,3002,12743720151935%2611127

2 41

2 98Lh 74

L u 57

L m 13%Lu 16

Lnm__m___ 15%Ln__m_m__ 35%4 __________4 u u__

L u 22%Ln 962 ]0

1_ _ _ _ _ _ _ _'_ _ __ _ _,_ _ _ _ _ _ _ _ __

1412

2_ _________u_ _ u__ _u ___ 10 dia. U _n _____ 34 in. __________ ~-3 n___ _ n _n 67 in. %2 n_ 32 in. Yg

2_u u_n_ u u 10 in. u-n !16

2 u__n___ _n___ u__ _u 12 in. J162 n___ u_u u _u 30 in. %L m___m 7% 10 8% uu .34 7%L mmm 3Y2 3% 2% n mm___= 1Y2

l n___L__u_________L_____________L_____________

64%108%16

__ __ _1__________

3 I6.80

m._u n_' .81

28%8384%7512%5% dia.17641% dia.1% dia.24916%101% dia.

113%44%77.,-

69%165%139

---------- 47777503

27510%IX8

aA set. consists of two cables matched electrically and tied In pairs.Note.-Thls list Is for general Information only. See appropriate supply publications for information pertaining to requisition

of spare parts. Additional parts are listed In paragraphs 28 and 88.

--------------------

- 1-__ 1__________15 1----------

- - - __ __ - - -1- ________ _1_ __ ___

8% 'n ~~~:~~~~__~~~~93/

I __

2 74 ___ -63% in. ' ~~~~__~~~~~~~_n' 12 in. '_On

- - - __ -1- ____ _.___ _______- __ - - - - - - -1- __ __ _ _ __ _1_ __ ___ - ___

-~~ ' ~~~ ~.'----------

41% 1-----_-------------- 8 in.

10%9y:! in. ----------

----------1.___ ----------

- -'-.- - - - - - -

11

Reqd No. Height Width Depth Length Volume Weightper unit (in.) (in.) (in.) (cu. ft.) (lb.) ea. I'

42_____________ ---..------ 1% ---------- 10%in. ---------- %

Lm__________'-_unn__110 ---------- 15 in. ---------- %

177.'1

I ]9 1----u----\217Ys 21% u____u__ 2.70

11. Description of Adcock Antenna(figs. 5 and 6)

a. The Adcock antenna system consists offour vertical monopole antennas erected in asquare array centered over a square wire-meshcounterpoise. The four monopole antennas cor-respond to the four cardinal compass points:north, east, south, and west.

b. To cover the frequency range of .54 to 10mc, the Adcock antenna system is erected witha monopole height of 29 feet and a spacing of33 feet.between pairs (A, fig. 5). To cover thefrequency range of 8 to 30 mc, a height of 22feet 4 inches and a spacing of 18 feet 10 inchesare used (B, fig. 5).

c. Four coaxial cables, one from each mono-pole, are individually routed to the center ofthe counterpoise. From the counterpoise cen-.ter, the entire group of four cables is routedunder and along a diagonal of the counterpoiseand then to the shelter.

d. Each monopole antenna is a four-sectionmast, called Antenna AS-533/GR (fig. 6). An-tenna AS-533/GR consists of the following:

(1) Antenna Section AT-445/GR (1, fig.6) is a 3J4-inch diameter, steel tubeapproximately 75 inches long. An in-ternally threaded sleeve in the upperend is used to attach the antenna load-ing disk. A locking lever at the lowerend is used to clamp it to the sectionbelow. .

(2) Antenna Section AT-444/GR (2, fig.6) is similar to Antenna Section AT-445/GR except that it is made of a'Va-inch diameter tube approximately100 inches long and has a guy platefastened to the upper end. A lockinglever at the lower end is used to clampit to the section below.

(3) Antenna Section AT-443/GR (3, fig.6) is similar to Antenna Section AT-444/GR except that it is made of1¥6-inch diameter, steel tube approxi-mately 100 inches long and has noguy plate. A locking lever at the lowerend is used to clamp it to the sectionbelow.

(4) Antenna Section AT-442/GR (4, fig.6) is a 1%,-inch diameter, steel tubeapproximately 100 inches long. The

12

mast insulator is built into this mastsection near the bottom. A ball at thelower end attaches the mast socketin the mast base. In the removablecylindrical antenna coupler (13, fig.6), located on the side of the mastinsulator above the ball, are two ter-minating resistors and an antennacable connector. A rubber hood pro-tects the cylindrical housing.

(5) Antenna Loading Disk MX-1168/GR(5, fig. 6) consists of four 5%-footloops which are arranged symmetri-cally about a common axis. The load-ing disk is mounted to the top ofAntenna Section AT-445/GR. Thepurpose of the loading disk is to im-prove sensitivity and to balance in thelow-frequency range. The loading diskmay be collapsed for shipment or stor-age purposes.

(6) The mast container (6, fig. 6) is pro-vided to store the antenna sections.The nylon guys (7, fig. 6) are providedto guy the erected monopole. The guyadapter (8, fig. 6) is used to connectthe nylon guy to the guy stake; onespare is provided. Four Guy StakesGP-2 (9, fig. 6) are used to anchorthe base to the ground, and anotherGuy Stake GP-2 is used to anchor anylon guy to ground. The locatingpins (10, fig. 6) are used to mark thelocation for erecting the monopole.The ground strap (11, fig. 6) is usedto connect the lower end of the an-tenna coupler to the counterpoise.

(7) Antenna Base MT-865/GR (12, fig.6) is a square wooden platform witha socket for the mast ball. A cutawayportion of the socket allows the mastto be lowered to a horizontal position.There are three leveling screws on thesocket for adjusting the mast verti-cally. Two pins are provided, one isused to lock the ball in the socket andthe other is used to keep the mastvertical. Four guy stakes are driventhrough the holes in the corner of thebase to anchor the base to the ground.Two guy plates for attaching the guysare secured to the base.

I

B.

tis mastn at the; socketmovable(13, fig.he masttwo ter-antennaood pro-

1168/GR51f2-foot

vmmetri-rhe load-e top of;R. Theis to im-:lcein the,ding diskIt or stor-

6) is pro-sections.

~provided. The guyto connect!take; oneuy Stakesto anchorld another) anchor aIe locating) mark the

monopole.6) is usedof the an-,erpoise.

R (12, fig.tform withA cutaway

I'Sthe masttal position.rews on themast verti-ided, one is~socket and:p the mast! are drivenorner of thethe ground.

ing the guys

A. LOW-FREQUENCY ANTENNA (.54-IOMC),33 F'T SPACING, FOUR SECTIONS AND LOADING DISK FOREACH MONOpOLE.

B. HIGH-FREQUENCY ANTENNA(S-30MC), 18 FT 10 IN. SPACING, THREE SECTIONS FOREACH MONOPOLE. TM688-56

Figure 5. Adcock a,ntenna, insta,Uations.

13

1 Antenna Section A T-445/GR2 Antenna Section AT-444/GR3 Antenna Section AT-443/GH.4 Antenna Section AT-442/GR

14

:3 5 6

9

10

TM 688:"122

5 Antenna Loading Disk MX-1l68/GR6 Mast, Container

. 7 Nylon guys .\: '; ..'8 Guy adapters9 Guy Stakes GP-2

Figure 6. Antenna AS-533/GR (Adcock monopole).

10 Locating pins11 Ground strap12 Antenna Base MT-865/GR13 Antenna coupler

c.3

'"'"'"c!-'"'-

r

e-.---

0)""I

8 I 1E1IiliI:Ii_&;£¥ii e-.

'"....,

,9 . " -

r I /

"" '"!-;:!....r.",

12. Descriptionof Antenna

AT-297/TRD-4 (Crossed-loop)(fig. 7)

The crossed-loop antenna consists of twoidentical diamond-shaped loop antennasmounted at a fixed angle of 90° with respect toeach other when installed on the roof of theshelter (C, fig. 7). The, loops, when installed,extend 4 feet 10 inches above the roof of theshelter. The loops have hinged joints at theoutermost corners, permitting them to be foldedwhen stowed (B, fig. 7). One loop can be re-moved and the other can be operated alone asa rotatable antenna (A, fig. 7). The 'vertical-

insulated rod at the center of the crossed-loopantenna serves as a mechanical support whenthe fixed crossed-loop antenna is used andserves as a sense antenna when the rotatablesingle-loop antenna is used.

13. Descriptionof CounterpoiseMX-1169/GRD(fig. 8)

Counterpoise MX-1l69/GRD assures uni-form ground conductivity for all four mono-poles of the Adcock antenna system. The coun-terpoise is a square approximately 75 feet oneach side when unfolded. It consists of nine75-foot by 8-foot sections of 18-inch mesh whichis constructed of No. 12 gage stranded, tinned,copper wire. Each section has an 8-foot woodenpiece at each end. The nine sections are joinedto one another by strips of ~-inch tinned, cop-per braid. The counterpoise is anchored to theground by 42 metal clamps that fit over thewooden end pieces. Four ground stakes andone spare are provided for grounding the cor-ners of the counterpoise. When folded, thecounterpoise is protected by a canvas wrap-around container, secured by straps.

16,-.

Figure 8. Unfolding Adcock antenna counterpoise.

14. DescriFAsse(fig.

Two whipone is used wother is usedEach whip alSections MS-A and Mast Iinch long ma~

Figu

~-_._.

es uni-. mono-le coun-feet onof nineh whichtinned,woodene joinedled, cop-d to the)ver thekes andthe cor-led, thes wrap-

)

14. Description of Whip AntennaAssemblies(fig. 9)

Two whip antenna assemblies are supplied,oneis used with the intercept receiver and theother is used with the communication receiver.Each whip antenna assembly consists of MastSectionsMS-1l6-A, MS-1l7-A, and MS-1l8-A and Mast Base AB-15/GR. The three 391/2-inchlong mast sections screw into one another

Figure 9. Whip antennas.J~:688-2~ .' :

and into the mast base to form a vertical an-tenna which is 10 feet 214 inches high. MastSection MS-1l6-A is three-eighths inch indiameter. Mast Section MS-1l7-A tapers fromeleven thirty-seconds inch to one-fourth inchin diameter, and Mast Section MS-118-Atapers from seven thirty-seconds inch to one-eighth inch in diameter. Mast Base AB-15/GRhas a coaxial connector for the antenna cableto the receiver.

15. Description of Radio Frequency Trans-mission Line Switch SA-346/GRD(Rf Switch)(fig. 10)

The radio-frequency (rf) switch is a two-position switch assembly located on top of theelectrical equipment cabinet (fig. 13). Its pur-pose is to select the direction finder (df) re-ceiver input either from the signal goniometeror from the rf amplifier.

a. When the R.F. SWITCH is in the GONIO-METER position, the signal starts in eitherthe Adcock or crossed-loop antenna, dependingon which antenna cables have been connectedto the signal goniometer.

Note. The ANT. SELECT. switch on the rf ampli-fier must be placed in the CROSSED LOOP position tocomplete the circuit when the cables from the crossed-loop antenna are connected to the signal goniometer.

q

~M688-121 !Figure 1.0. Radio Frequency Transmission

.. . Line Switch SA-346/GRD.

lIi

17'

b. When the rf switch is in the R.F. AM-PLIFIER position, the signal may start ateither the sense or single-loop antenna, depend-ing on the setting of the ANT. SELECT. switchlocated on the rf amplifier. In the MONITORposition of the ANT. SELECT. switch, thesignal starts at the sense antenna. In theSINGLE LOOP position of the ANT. SELECT.switch, the signal starts at the single-loopantenna.

16. Description of Switch Box SA-345/U(fig. 11)

u. Switch Box SA-345/U is a portable metalbox 8% inches high, 111,4 inches wide, and 9inches deep, which houses a heavy duty 60-ampere, two-pole, four-position rotary switch.It is used to connect the output of anyone ofthree power sources (115/230 volts, 50 to 60cycles per second (cps» to Direction Finder

Set AN/TRD-4A. Four additional sets of ter-minals are available for connecting four otherequipments if desired. Two convenience outletsfor electrical accessories are also provided.

b. At the bottom of the switch box, openingsfor three input cables and five output cablesare provided and equipped with clamps. Thecable terminals connect to %6-inch screw-typeposts on two terminal boards inside the switchbox. To facilitate attachment of the cables, thebp and side covers of the switch box may bereadily removed by unhooking the four springclamps. The switch knob and convenience re-ceptacles are recessed into the front of theswitch box for protection. Two handles andtwo straps are provided to permit carryingthe switch box and attaching the switch boxto a stake driven into the ground or to the sideof a trailer associated with the power unit(fig. 30).

18

Figure 11. Switch Box SA-9J,.5/U.

17. DescrJ-~(fiJ

Junctiontrol and di:from eithecommercialequipment.

ter-;herlets

.ngsblesThetype'itchthe

'f bering~ re-

theand

yingboxsideunit

17. Descriptionof Junction BoxJ-95BjCRD-2(fig. 12)

Junction Box J-95B/CRD-2 acts as a con-trol and distribution point for the power fedfrom either the mobile power units or acommercialpower source to the electronicequipment.The junction box contains an auto-

transformer with an OUTPUT VOLTAGECONTROL for adjusting the output voltage to115 volts when there is not more than 10-percent variation of input voltage (103 to 127 v.or 207-253 v.). A LINE FREQUENCY meter,an OUTPUT VOLTAGE meter, CIRCUITBREAKERS, LINE INPUT and OUTPUTLOAD switches are located in recessed frontpanels. Dummy load resistors, capable of dis-

rI TM6SS-S6r. 1.

, Figure 12. Junction Box J-95B/CRD-2.

1I

I1

19

"",~,~_TM..~aa-IQ6,.

Figure 13. Electrical Equipment" Cabinet CY-11,26/U. components installed.

19. DesciM;(fi

a. The gjprovides tbthe signal ~meter simu:which is prof the goni(JThe bearinJnull operat:goniometerhorsepowera belt arrar

20

-- _.-

sipating 4box. ThE

making pline voltait is appl115-volt ainput conijunctionprovided I

Warn in

ience outlminal box(fig. 92).

18. DeslC(

Electrica reinforlinches wi<deep.

a. Openthe rack p.on the Va]metal serequate cro~shock mouelectrical fthe uppertional shoe

b. The Iered paneGoniomete:IndicatorR-390/URelectrical e

c. The relectrical e

Ii

,

sipating 400 watts, are provided in the junctionbox. These resistors serve as a load whilemaking preliminary adjustments to allow theline voltage to be adjusted to 115 volts beforeit is applied to the electronic equipment. One115-voltac input connector and one 230-volt acinput connector are provided on one side of thejunction box and five ouput connectors areprovided on the opposite side.

Warning: The heater, blower, and conven-ience outlets must be disconnected at the ter-minal box when a 230-volt power source is used(fig. 92).

18. Description of Electrical EquipmentCabinet CY-1426/U(fig. 13)-

Electrical Equipment Cabinet CY-1426/U isa reinforced steel frame approximately 21inches wide, 343;4 inches high, and 20 inchesdeep.

a. Openings 10 by 23 inches on each side ofthe rack provide access to the cable connectionson the various chassis. Removable perforatedmetal screens inclose the sides and allow ade-quate cross ventilation of the cabinet. Fourshockmounts are secured to the bottom of theelectrical equipment cabinet. Holes located atthe upper rear of each side are used for addi-tional shock mounts.

b. The rear of the rack is inclosed by louv-ered panels and two cable entrance doors.Goniometer Drive MX-1170/GRD, AzimuthIndicator IP-137/GRD, and Radio ReceiverR-390/URR (df receiver) are mounted in theelectrical equipment cabinet.

c. The rf switch is mounted on top of theelectrical equipment cabinet.

19. Descriptionof Goniometer DriveMX-1170/GRD(fig. 14)

a. The goniometer drive is the assembly thatprovides the means for turning the rotors ofthe signal goniometer and the indicator gonio-metersimultaneously. A bearing indicator scalewhichis protected by a door on the front panelof the goniometer drive is calibrated in degrees.The bearing indicator scale is used for aural-null operation and is directly coupled to thegoniometer rotors that are driven by a ¥Is-horsepowerelectric motor through a pulley anda belt arrangement.

b. The assembly mounts on a chassis 121¥I6inches by 17%6 inches with a standard rackmounting panel 19 inches wide by 101;2incheshigh. The goniometer drive is mounted in thetop compartment of Electrical Equipment Cabi-net CY-1426/U (fig. 13). Built-in slides permitthe unit to be pulled forward when changingthe signal goniometer or when making orienta-tion adjustments.

c. The unit houses the goniometer drivemotor, drive assembly, bearing indicator scale,signal goniometer, and indicator goniometer.

(1) Goniometer drive motor B701 is a¥Is-horsepower, induction-type motorthat drives the bearing indicator scale,signal goniometer rotor, and indicatorgoniometer rotor.

(2) The drive assembly couples the me-chanical output of the goniometerdrive motor to the bearing indicatorscale and the goniometer rotors.

(3) The bearing indicator scale is cali-brated in degrees and indicates thebearing of a transmitter when theequipment is being operated in theaural-null mode.

(4) Electrical Goniometer GO-5/GRD orGO-6/GRD may be used as the signalgoniometer, depending on the fre-quency. The signal goniometer re-solves the signals from the antennasinto one component which is coupledto the df receiver.

(5) Electrical Goniometer GO-5/GRD isused as the indicator goniometer. Theindicator goniometer resolves the sig-nal from the df receiver back into twocomponents that are applied to thedeflection plates of the cathode-raytube. The indicator goniometer islocated on the left side of the gonio-meter drive unit.

20. Description of Electrical GoniometersGO-S/GRD and GO-6/GRD(fig. 15)

a. The signal and indicator goniometers arecylindrical units that are end-mounted and haveone flat side that serves as a back plate forconnectors and a switch. Mounted on the endof the rotor shaft is a cylindrical coupling witha spring-loaded plunger used to engage therotor shaft with the goniometer drive.

21

22

l

TM688-77

Figure 14. Goniometer Drive MX-1170/GRD.

b. Internally, each signal and indicator gonio-meter contains two stator windings, a rotatingarmature with a rotor winding, and a rotarytransformer. In addition, there is a sens.ephas-ing network of resistors and capacitors, and inElectrical Goniometer GO-6/GRD, an inductor.A sense relay, signal input and output con-nectors, a relay excitation connector, and aSENSE PHASE switch on the backplate com-plete the unit. Each unit is 5% inches highby 4% inches wide by 8% inches long.

c. Three goniometers are provided, one high-frequency (GO-6/GRD) and two low-frequency(GO-5/GRD) types. A low-frequency gonio-meter is used as the indicator goniometer (orresolver) . Either a high- or low-frequencygoniometer may be used for the signal gonio-meter, depending on the frequency of the re-ceived signal. For signals in the range of .54to 10 me, a low-frequency goniometer is usedand for signals in the range of 8 to 30 me, ahigh-frequency goniometer is used. The signal

INDICATORGONIOMETER

goniometer combines the outputs of the north-south and east-west antennas into one signalthat is fed to the df receiver; the indicatorgoniometer resolves the signal back into twocomponents of proper phase and amplitude,which are applied to the horizontal and verticaldeflection plates of the azimuth indicatorcathode-ray tube. The external appearance ofElectrical Goniometer GO-5/GRD is illustratedin figure 15. Figures 125 and 126 are schematicdiagrams for Electrical Goniometers GO-51GRD and GO-6/GRD.

21. Description of Azimuth IndicatorIP-137/GRD(fig. 16)

a. Azimuth Indicator IP-137/GRD consistsof a chassis 17 by 17 inches with a standardrack mounting control panel 19 inches wide by10% inches high, complete with 10 tubes in-cluding a 5-inch cathode-ray tube. The operat-ing controls, df receiver loudspeaker, power

Figure 15.

control switcmounted on tcator aceom:controls the

CAPTIVESCREW

l

PTIVEREW

A688-77

Ie north-Ie signalindicatorinto two

nplitude,l verticalindicator~rance oflustratedichematics GO-51

Cltor

) consistsstandard

s wide bytubes in-1e operat-ar, power

COUPLING TM688-21

Figure 15. Electrical Goniometer GO-5/GRD.

control switches and alidade scale assembly aremounted on the front panel. The azimuth indi-cator accommodates the connectors for andcontrols the applicatio.n of line power to all

components in the electrical equipment cabin~t.Additional receptacles for interconnecting theazimuth indicator, df receiver, and goniometerdrive assembly are available at the rear of thechassis. The azimuth indicator includes a self-contained regulated 275-volt B+ power supplyand a -2,000-volt high-voltage power supplyfor the cathode-ray tube. The -2,000-volt poten-tial is supplied by one replaceable unit desig-nated as Power Supply PP-988/GRD (fig.105). The input voltage requirements are 115volts, 50 to 60 cps and the power consumptionis 100 watts. The azimuth indicator fits intothe center compartment of the electrical equip-ment cabinet (fig. 13) and is held in place byfour captive screws. Handles are provided tofacilitate removal of the azimuth indicator forservicing.

b. The azimuth indicator is provided with analidade and a lighted azimuth scale around the5-inch cathode-ray tube. The rotatable alidadeembodies cross hairs to facilitate reading the

CAPTIVESCREW

Figure 18. Azimuth Indicator IP-187/GRD.

23

bearings and is equipped with a light shield.The alidade assembly enables accurate bearingand sense determination from the propeller-shaped visual display.

22. Description of Radio ReceiverR-390/URR(fig. 13)

a. Radio Receiver R-390/URR is a 33-tubegeneral purpose radio receiver with a self-contained power supply that operates from a115-volt, 50- to 60-cps, ac power source. Theoperating controls, CARRIER LEVEL andLINE LEVEL meters, PHONES jack, and anaccurate frequency indicating dial, are locatedon the front panel. Power input and outputconnectors, operating and spare fuses, tubepullers, and pin straighteners are located onthe back panel. Radio Receiver R-390/URR iscomposed of a main frame, front panel, backpanel, and seven subchassis.

b. The radio receiver is designed for mount-ing in a 19-inch rack. Two handles are pro-vided at the outer edge of the front panel tofacilitate withdrawal of the radio receiver fromthe rack or case. Three Radio Receivers R-390/URR are provided with Direction FinderSet AN/TRD-4A. One of the receivers, usedas the df receiver, is mounted in the bottomcompartment of the electrical equipment cabi-net (fig. 13). One of the receivers, used as theintercept receiver, is provided installed in acabinet that is mounted on top of the operatingtable, to the left of the electrical equipmentcabinet (23, fig. 19). The other receiver, usedas the communication receiver, is provided in-stalled in a cabinet that is mounted on top ofthe operating table, to the right of the electricalequipment cabinet (18, fig. 19).

c. Instructions for the installation, operation,and maintenance of the receivers are containedin TM 11-856, Radio Receiver R-390/URR.

23. Description of Radio FrequencyAmplifier AM-496/TRD-4(fig. 17)

a. Radio Fr~quency Amplifier AM-:,-496/TRD-4 is a three-tube prearpplifi-er used duringsingle-loop, a;u~I-~!111operation. The case thatcontains the pteamplifier is a housing for the

~shaft, 'bearings, and slip rings for the crossed-loop and sense antennas and is also a mounting,

2~

for the antennas. The rf amplifier is attachedto the ceiling of the shelter and the antennamounting section extends above the roof. AnANT. SELECT. switch built into the unitallows the loop antennas to be used for eitherrotatable single-loop, aural-null operation withthe rf amplifier, or fixed crossed-loop operation.A hand wheel and an azimuth scale are pro-vided for manually rotating the loop duringsingle-loop, aural-null operation. The over-alldimensions of the case are approximately 22%inches high by 6% inches deep.

b. The self-contained power supply is de-signed for operation from a 115-volt, 50- to60-cps ac power source. The power consump-tion is 18 watts. The output impedance of therf amplifier is 100 ohms and the frequencyrange is from .54 me to 30 me in five bands.

c. The antenna base consists of a rotatableportion and a fixed portion. The rotatable por-tion is connected by a shaft to a handwheel inthe shelter. The fixed portion is supported ina fixed position relative to the shelter roof. Therotatable portion contains the sockets for thefour legs of the crossed-loop antenna and forthe single-loop sense antenna.

24. Description of Radio TransmitterT-279/UR(fig. 18)

a. Radio Transmitter T-279/UR is a self-contained, battery-powered portable unit usedas a target transmitter or signal source forcalibrating and checking the operation of thedirection finder equipment in the field. Theradio transmitter emits a low-power, continu-ous-wave (cw) or modulated continuous-wave(mew) signal. For identification of the signal,an audio-frequency (af) tick is superimposedon the rf signal approximately every 2 seconds.The radio transmitter feeds a monopole antennamounted on the top of the radio transmittercase. The radio transmitter normally rests onthe ground during operation.

b. All Component parts incl,uding the bat-terie~ are ho~d in a sheet steel case. A hingedcover on top 6f the case protects the operatingcontrols that are located on the top panel. Thehing~d cover is splashproofed by means of arubber gasket around the edge and is equippedwith a metal carrying handle. A neon lamp,which is part of the ticking circuit, is located

"-"~~", . >.~..~.

r~MP1.1FIER. A.F.' At.1-496/TRD.4

.$f.,Al"O_ O""~"_'_'Q''''''''. stP\, (:QPI'N'l'I"" tr "I,"'~'('A' ":

"I"..~ ,O: <'t'H ..I

tachedntennaIf. Ane uniteither

In with!ration.re pro-during

over-all!ly22%

. is de-. 50- tomsump-:e of the'equencyoands.~otatableablepor-wheel in)Qrted in'oaf. The~ for theI and for

~.

..~," "". . ...,,:.

.~

is a self-unit used;ource forion of thefield. Ther, continu-luaus-wavethe signal,)erimposed, 2 seconds.:>leantenna;ransmitterIly rests on

AZIMUTHSCALE

HANDWHEEL

itter

19the bat-~. A hinged.e operatingpanel. Themeans of ais equippedneon lamp,

t, is located

TM688-115

Figure 17. Radio Frequency Amplifier AM-496/TRD-4.

25

on the top panel and is used as a power onindicator.

c. The antenna consists of five telescopingchromium-plated brass sections, adjustable to a5-foot length. The telescoped sections may bestored within the base by sliding the sectionsthrough the insulated bushing mounted on the

ANTEN N A

KNURLEDHOLD-DOWNSCREW!-----

TM688-31

Figure 18. Radio Transmitter T-279/UR.

26

top panel. Splashproofing of the feedthroughbushing is accomplished by a rubber seal. Aspring clip under the insulator makes contactwith the antenna to hold it in position andalso to connect it to the transmitter circuits.

d. One 135-volt Battery BA-424/U and one1.5-volt Battery BA-404/U supply the powerfor the radio transmitter. The 1.5-volt A bat-tery supplies the required filament power. The135-volt B battery supplies all operating poten-tials for the remaining circuits. The batteriesare not supplied with the radio transmitter andmust be requisitioned. Directions for installingthe batteries are outlined in paragraph 42.

25. Description of Shelter S-44A/G(figs. 19 and 20)

Shelter S-44A/G is a knock down-type fieldand mobile shelter used to house all the equip-ment of Direction Finder Set AN/TRD-4Aexcept the generator sets and to provide roomfor three operators. The outside of the shelteris 139 inches long by 74 inches square; it willfit in the cargo body of a 2¥2-ton 6x6 truck.Four tow rings, one at each lower corner, andfour tie-down fittings at each upper corner areprovided. The upper fittings hinge outward tokeep the hold-down bars away from the sheltersides.

a. Shelter. The shelter consists of a one-piece rigid floor and a one-piece top sectionjoined by wall panels. Two doors and fourwindows are equipped with screens and black-out blinds; a blackout curtain is included forone door.

b. Roof and Corner Sections. The roof sec-tion and four corner sections embody metalscreening that forms a shield which minimizesloop errors caused by reradiation from electro-static and electromagnetic fields generatedwithin the shelter.

c. Ventilating System. The ventilating sys-tem consists of a motordriven blower (13, fig.19) mounted in the roof section of a manuallyoperated blower outlet opening. Two lightproof"riiustable louvers, equipped with removablefilters, filter the intake air.

d. Shelter Electrical System. Two racewayswith 16 receptacles for U5-volt, 60-cps, acservice are provided on the shelter ceiling.These receptacles comprise 12-plug receptaclesand four midget twist-lock receptacles. The

wiring jual reseat 35 anbreaker~ceiling hand theare plug,

e. Sheshelter hpanel ofmaintainwithin tJconsists (fuel tankdrain.

(1)

1 Storage (2 Fire extit3 Lamp4 Electrical

CY-1425 Radio Frl

Switch6 Goniomet,7 Electrical8 Electrical9 Azimuth]

10 Loudsveal

idthroughr seal. A~scontactition andcircuits.

J and onethe powerolt A bat-)wer. Theing poten-~batteriesmitter and. installing3.ph42.

"'/G

a-type field. the equip-~/TRD-4Aovide roomthe shelter

.are; it will6x6 truck.

corner, and, corner areoutward to

1the shelter

s of a one-top section

rs and four.s and black-included for

Irhe roof sec-nbody metal~hminimizesfrom electro-ls generated

ntilating sys-)wer (13, fig.)f a manuallywo lightproofth removable

TworacewaysIt, 60-cps, acaelter ceiling.ug receptacleseptacles. The

wiring for the raceway terminates in two man-ual reset-type overload circuit breakers ratedat 35 amperes, 120 to 240 volts ac. The circuitbreakers (28, fig. 19) are located near theceilingin a junction box. The ventilating blowerand the heater, both operating on 115 volts,are plugged into the nearest ceiling receptacle.

e. Shelte1' Heater Unit (16, fig. 19). Theshelter heater unit is mounted on a modified endpanel of the shelter. The heater is used tomaintain a comfortable working temperaturewithin the shelter in cold weather. The unitconsists of a heater, inlet louver, exhaust pipe,fuel tank, fuel line, fuel drain, and water trapdrain.

(1) The heating unit is a gasoline-burning,electrically operated space heater. Theheater operates from a 115-volt, 50-to 60-cps, ac power source. The

heater is rated to deliver 60,000 Brit-ish thermal units per hour. The over-all dimensions of the heater cabinetare approximately 28 inches high, 11inches deep, and 2414 inches long.Outside air may be drawn in throughthe louver in the shelter wall or insideair may be drawn through the grillin front of the cabinet near the topand warm air discharged at the frontof the cabinet near the floor.

(2) The unit can also be used for ventila-tion in which case only the heaterventilating fan motor is in operation.

(3) The heater is fully described in themanual shipped with the heater.

f. Loading Skids (13, fig. 20). The tW0loading skids are made of high-tensile steel.Each skid has a hook at one end to secure the

TME:8S-IIO

Storage cabinetFire extinguisherLampElectrical Equipment Cabinet 13

CY-1426/U 14Radio Frequency Transmission Line 15

Switch SA-346/GRD 166 Goniometer Drive MX-1170/GRD 177 Electrical Goniometer GO-5/GRD 188 Electrical Goniometer GO-6/GRD 199 Azimuth Indicator IP-137/GRD 20

10 Loudspeaker LS-166/U

11 Desk lamp12 Radio Transmitter T-279/UR

(stowed)BlowerAntenna Base MT-865/GR (stowed)Junction Box J-95B/CRD-2HeaterOperator's chairCommunication receiverDf receiverLadder strap and buckle assembly

21 Ladder22 Operating table23 Intercept receiver24 Cable Payout Reel RL--I74/G

( stowed)25 Cable Assembly Set CG-I097/TRD-4

(2 sets)26 Electrical Power Cable Assembly

CX-2380/U27 Terminal box28 Circuit breaker

Figure 19. Location of equipment in shelter, left side.

27

skid to the tailgate hinge pin of a 21f2-ton 6 x 6cargo truck. .

g. Ladder (21, fig. 19). The 8-foot ladderfolds at the center and has fittings to permit itto be locked in either the open or closed position.

h. Tools. One l/2-inch wrench used to oper-ate the fasteners and one screwdriver areprovided. .

i. Joining Cover (11, fig. 24). The mildew-resistant canvas joining cover provides a meansof joining two shelters end-to-end to form alarger inclosure. The joining cover is not usedfor this purpose in Direction Finder Set AN/TRD-4A but is supplied in the interest of shel-ter standardization.

j. Hold-Down Bars (14, fig. 20). Four ad-

justable hold-down bars are provided to securethe shelter when it is mounted on or while itis being transported in a 21f2-ton 6 x 6 cargotruck. One end of a bar is hooked into a tie-down fitting on the roof section and the otherend is hooked over the side board of the truck.The length of the bar is adj usted by means ofthe turnbuckle. Hold-down bar extensions (15,fig. 20) are provided to lengthen the bar by10 inches.

k. Additional Information. Instructions forthe installation, operation, and maintenance ofthe shelter are contained in TM 11-2599, Shel-ters S-44jG and S-44A/G. The location of theequipment in the shelter is illustrated in figures19 and 20.

2 3,4,5,6,7,8 9

17

16

~5 14

1 Convenience outlets2 Radio Frequency Amplifier

AM-496/TRD-43 Antenna Section AT-445/GR

(5 ea stowed)4 Antenna Section AT-444/GR

(5 ea stowed)5 Antenna Section AT-443/GR

(5 ea stowed)

13 12 10, II 3,4,5,6,7,8

TM688-I09

Antenna Section AT-442/GR 12(5 ea stowed) 13

7 Antenna Loading Disk MX-1168/GR 14(5 ea stowed) 15

8 Antenna mast container (5 ea) 169 Blackout curtain 17

10 Counterpoise MX-1169/GRD(stowed)

11 Counterpoise container (stowed)

Ground rods (5 ea stowed)Loading skids (2 ea)Hold-down bars (4 ea)Hold-down bar extensions (4 ea)Antenna AT-297/TRD-4 (stowed)Antenna Base MT-865/GR

(4 ea stowed)

28

Figure 20. Location of equipment in shelter, right side.

26. Descria. Gener<J

supplied wi'4A are perseveral extePayout Ree]cables are S.operating t:43) lists thcates in theis normallypayout reel.

b. Radio1078/U (2 J

sists of 2 :Cable RG-1UG-21B/Uassembliesare providel

c. Radio1079/U. 'IFrequency I

nector UG/cable assemby differeni

( 1) 01(V

(2 ) 01(V

(3) T,an

( 4) 01(V

d. Cable,It). This I

electricallyof 170 fee113A/U witton each en(consists of .W103 andspares.

e. CableIt). This I

electricallyof 9 feet ofwith Radioend. Threeof W201 arand W204,

I. Radio1379/U (14

.il II", ll\ \

D''* @Ijl\ \ ., . '::L I II

, " , ,111I

litII I

I

!cureHe it:argoa tie-othertruck.ms of.s (15,lar by

ms formce ofI, Shel-l of thefigures

9I

.\,II 3,4,5,6,7,8

TM688-I09

stowed)l)ea)

enslons (4 ea)'RD-4 (stowed)-865/GR

26. Description of Cords and Cablesa. General. Most of the cords and cables

supplied with Direction Finder Set AN/TRD-4A are permanently installed in the shelter,several external cables are contained in CablePayout Reel RL-174/U (fig. 21), and the spa ecablesare stowed in the storage bins under theoperating table. The cable check chart (par.43) lists the function of each cable and indi-cates in the Remarks column whether the cableis normally installed or contained in the cablepayout reel.

b. Radio Frequency Cable Asser.~bly CG-l078/U (2 ft 6 in.). This cable assembly con-sists of 2 feet 6 inches of Radio FrequencyCableRG-13A/U with a Radio Frequency PlugUG-21B/U on each end. Four of these cableassemblies (W401), W402, W403, and W404)are provided.

c. Radio Frequency Cable Assembly CG-l079/U. This cable assembly consists of RadioFrequency Cable RG-22B/U with a Plug C:m-nector UG/421-U on each end. Five of thesecableassemblies are provided and distinguishedby different lengths.

(1) One 8-foot 6-inch cable assembly(W205) is provided.

(2) One 2-foot lO-inch cable assembly(W405) is provided.

(3) Two 2-foot cable assemblies (W501and one spare) are provided.

(4) One 3-foot 5-inch cable assembly(W304A) is provided.

d. CableAssembly Set CG-l 097/T RD-4 (170It). This cable assembly set consists of twoelectricallymatched cables. Each cable consistsof 170 feet of Radio Frequency Cable RG-13AlU with Radio Frequency Plug UG-21B/Uon each end. Four sets are provided, one setconsistsof W101 and W102, one set consists ofW103and W104, and the other two sets arespares.

e. Cable Assembly Set CG-l098/TRD-4 (9ft). This cable assembly set consists of twoelectricallymatched cables. Each cable consistsof 9 feet of Radio Frequency Cable RG-13A/Uwith RadioFrequency Plug UB-21B/U on eachend. Three sets are provided, one set consistsof W201and W202,one set consists of W203andW204,and the other set is a spare.

/. Radio Frequency Cable Assembly CG-l379lU (14 ft 6 in.). This cable assembly con-

sists of 14 feet 6 inches of Radio FrequencyCable RG-13A/U with Plug PL-259/U at oneend and a Plug Connector UG-573/U at theother end. Two of these cable assemblies(W1007A and W1008A) are provided.

g. CQ1'dCG-409E/U (2 ft 3 in.). This cordconsists of 2 feet 3 inches of Radio FrequencyCable RG-58C/U with a Radio Frequency PlugUG-88C/U at each end. One of these cords(W303A) is provided.

h. Electrical Power Cable Assembly CX-2377/ U (2 ft 8 in.). This cable assembly con-sists of 2 feet 3 inches of two-conductor cablewith a female plug #AN-3108A-14S-9S onone end and two soldering lugs on the otherend. One of these cable assemblies (W302) isprovided.

i. Electrical Power Cable Assembly CX-2378/U (3 ft). This cable assembly consistsof 3 feet of 2-conductor cable with a femaleplug #AN-3106A-12S-3S on one end and amale plug #AN-3108A-12S-3P on the otherend. Two of these cable assemblies (W301 andone sp'ilre) are provided.

j. Electrical Powe1' Cable Assembly CX-2379/U (2 ft 6 in.). This cable assembly con-sists of 2 feet 6 inches of four conductor cablewith a female plug #AN-3106A-14S-5S onone end and a male plug #AN-3108A-14S-5Pon the other end. One of these cable assemblies(W701) is provided.-k. Electrical Power Cable Assembly CX-

2380/U (20 ft). This cable assembly consistsof 20 feet of two-conductor cable with two ter-minal lugs on each end. Four of these cableassemblies (W801, W802, W803, and one spare)are provided. _

l. Electrical Power Cable Assembly CX-2381/U (.ft). This cable assembly consistsof two-conductor cable with a Harvey Hubbellconnector No. 7238 at one end and a HarveyHubbell connector No. 7224 at the other end.Two of these cable assemblies are provided, one(W901) is 8 feet and the other (W902) is 10feet long.

m. Electrical Power Cable Assembly CX-2382/U (10 ft). This cable assembly consistsof a two-conductor cable with a Harvey Hubbellconnector No. 7224 on one end and two ter-minallugs on the other end. One of these cableassemblies (W903) is provided.

n. Electrical Power Cable Assembly CX-2383/U ( ft in.). This cable assembly con-

29

sists of two-conductor cable with a HarveyHubbell connector No. 7224 on one end and twoterminal lugs on the other end. Two of thesecable assemblies are provided, one which is 16feet long and is used as W1001 and the otherwhich is 3 feet 4 inches long and is used asW1002.

o. Electrical Power Cable Assembly CX-2384/U (9 It). This cable assembly consistsof 9 feet of two-conductor cable with terminallugs on one end and the other end is unproc-essed. One of these cable assemblies is providedand used as W1003.

Figure 21. Cable Payout Reel RX-174/G.

27. Description of Minor Componentsa. Compass (fig. 27). For orienting the Ad-

cock antenna and the loop antennas duringinstallation, a compass, a ball and socket, andan adapter are furnished.

b. Tripod (7, fig. 24). A tripod is used with

30

the compass to orient the Adcock antenna withtrue or magnetic north during installation.

c. Operator's Chairs (17, fig. 19). Threeoffice-type chairs for the operators are fur-nished with Direction Finder Set AN /TRD-4A.

d. Cable Payout Reel RL-174/G (fig. 21).The cable payout reel supplied with DirectionFinder Set AN /TRD-4A is a cable reel mountedin its own transport case. The cable payoutreel facilitates laying and rewinding of themain power cable and Adcock antenna cables.

e. Storage Cabinet (1, fig. 19). A storagecabinet with three drawers is provided on oneend wall of the shelter. The equipment storedin these drawers is as follows:

(1) The equipment stored in the bottomdrawer is illustrated in figure 22.

(2) The equipment stored in the middledrawer is as follows:

(a) Receiver spares (par. 28e)(b) Radio transmitter spares (par. 28b)(c) Headsets and cords (2 and 3, fig. 25)(d) Telegraph key (11, fig. 25)(e) Special tools kit (4, fig. 25)

(3) The equipment stored in the topdrawer is as follows:

(a) Azimuth indicator spares (par. 28a)(b) Rf amplifier spares (par. 28c)(c) Goniometer drive spares (par. 28d)

I. Operating Table (22, fig. 19). Most ofthe major components of the direction finderset mount on a pipe frame table secured to theshelter floor. The operating table includes stor-age bins underneath and an armrest along thefront, with lift-up doors and storage spacesinside. These storage spaces and their contentsare listed in (1), (2), and (3) below:

(1) Contents of the left side of the storagebin are shown in figure 23.

(2) Contents of the right side of the stor-age bin are shown in figure 24.

(3) Items of equipment stored in the arm-rest and middle drawer of the storagebin are shown in figure 25.

g. Tools. A set of tools for installing andrepairing the direction finder set is includedwith the equipment (par. 88).

h. Gasoline Engine Generator Set PU-236/G.Two generator sets are supplied as part ofDirection Finder Set AN /TRD-4A. Up tothree generator sets may be used alternatelyin 8-hour shifts. Three generators allow one

standby unitthe third is iSet PU-236/'Unit PU-58/power unit60-cps, singlcapacity is 56.25 kilovolt-tor. Refer 158/G, for de

i. Othe1' (parts descritFinder Set 1fuses and larstake adaptecontainer, gl166/U.

28. RunnilNote: The

are also listeda. Azimut

Spare V1 t

I3J

14~

~15 ~/fJ

1 Switch Bo:2 CompaSs c3 Compass4 Ban and s

nna withation.

Threeare fur-

rRD-4A.(fig. 21).Directionmounted

le payoutg of thela cables.

\. storage~d on onemt stored

Ie

~)par. 28b)3, fig. 25)))the

:par.28a)28c)par. 28d)

Most ofion finderred to theudes stor-along thege spacesr contents

f the stor-24.

n the arm-he storage

>U-236/G.

.s part of\.. Up to'tlternatelyallow one

'1

10

1 Electrical Power Cable AssemblyCX-2380/U (20 ft)

2 Guy stakes and container3 Hammer4 Bag for counterpoise clamps5 Grounding straps

9 e 7

6 Counterpoise clamps7 Locating pins and container8 Layout template chain9 Guy stake adapter

10 Nylon guys

11 Bag for locating pins and layouttemplate

Gag for g-uysTelephone mounting bracketTelephone EE-8-BSkid rope 1'4 -inch (100 ft)

1 Cable As!(170 ft

cables'2 Mast Bas:I Mast Bas4 Mast Sec.

12131415

Contents of storage bin, left side.Figure 23.

c. Rf Amplifier Spares.Spare tubes.

1 type 6AU6 pentode.1 type 6X4W rectifier.

Spare dial lamps.2 Lamps LM-52.

Spare fuses.6 Bussman type AGC %-ampere

fuses.

d. Goniometer Drive Spares.Spare lamp.

1 Lamp LM-52.

e. Receiver Spares.Spare tubes.

2 type 3TF7 voltage regulators.6 type 6AJ5 pentodes.2 type 6AK6 pentodes.1 type 6BH6 pentode.

32

3 type 6BJ6 pentodes.6 type 6C4W triodes.1 type 12AT7 dual triode.3 type 12AU7 dual triodes.1 type 26Z5W rectifier.1 type 5651 voltage regulator.4 type 5749 6BA6W pentodes.1 type 6082 dual triode.

Spare fuses.6 type 3AG 3-ampere fuses.6 type 3AG %-ampere fuses.

Spare dial lamps.4 type GE 327 lamps.

f. Heater Spares.1 type AG6-12 volt spare plug.1 type XEJ-14-2 electrode.1 electrode gasket.1 tank gasket.1 hmk fitting.

g. Shelter3 keys.3 cord i

10 panelh. Adcock

1 Anter1 Anter1 Anter1 Anter1 Anter1 anten6 grOUIJ1 Anter1 anten6 guy 25 Guy:

Z

i

15------12

3

14

-4

1113

IZ ... ::i:¥:"8 " -- - - -5

6;a- ........... ILtI'iiiIiIL..L 1Ri8;...aljl......-.;.? --. ,w",._.", :!::. ...........-

II

,..-z ,

1688-139

).out

'.I,

10

Cable Assembly Set CG-1097/TRD-4(170 ft) (a set consists of twocables electrically matched)

2 Mast Base Brackets MP-503 Mast Bases AB-15/GR. Mast Sections MS-118-A

9

I

I,

,,~

I

I

,

TM688'1~~ j8 7

5 Mast Sections MS-117-A6 Mast Sections MS-116-A7 Tripod with adapter and cap8 Electrical Power Cable Assembly

C7-2378/U (3 ft)9 Radio Frequenc). Cable Assembly

CG-1079/U (2 ft)

10 Cable Assembly Set CG-1098/TRD-4(9 ft) (a set consists of twocables electrically matched)

11 Shelter joining cover12 Electrical Power Cable Asse~bly

CX-2380/U (20 ft)

Figure 24. Contents of table storage bin, right side.

g. Shelter Spares (Stowed in Floor Cavity).3 keys.3 cord grip caps.

10 panel fasteners.

h. Adcock Antenna Spares.1 Antenna Section AT-442/GR.1 Antenna Section AT-443/GR.1 Antenna Section AT-444/GR.1 Antenna Section AT-445/GR.1 Antenna Base MT-865/GR.1 antenna coupler.6 ground straps.1 Antenna Loading Disk MX-1168/GR.1 antenna mast container.

6 guy adapters.5 Guy Stakes GP-2.

3 nylon guys.10 locating pins.

i. Whip Antenna Spares.1 Mast Section MS-116-A.1 Mast Section MS-117-A.1 Mast Section MS-118-A.

j. Spare Cables.2 Cable Assembly Sets CG-1097/TRD-4

(170 ft).1 Cable Assembly Set CG-1098/TRD-4

(9 £1).1 Radio Frequency Cable Assembly

CG-1079/U (2 ft).1 Electrical Power Cable Assembly

CX-2378/U (3 ft).1 Electrical Power Cable Assembly

CX-2380/U (20 ft).

33

8

1- . .--6

..-..-- -- - --

1 Literature2 Cords for headset3 Headsets4 Special tool kit ba~

5 Steel tape, 50-foot6 Allen wrenches7 Tube adapters8 Tube extractor

9 AJlnement tools10 Antistatic wax11 Telegraph Key J-4712 Screwdrivers

13 Test cable, rf amplifier

2

29. AdditionNot S

Batteries arRadio Transminished with thEbe requisitione

1 Batteryhigh 1

1 Batteryhigh'

j

I

'j

J

TM668-123

Figure 25. Contents of armrest and storage cabinet, middle drawer.

I,/

2,/

4,/