r TM 11-688 TECHNICAL MANUAL 1 DEP ARTMENT OF THE ARMY No. 11-688 ) WASHINGTON25, D. C., 24 June 1955

DIRECTION FINDER SET AN/TRD-4A

Paragraphs Page CHAPTER 1. INTRODUCTIOK Section I. General______1,2 3 II. I;escription and data_h__nh hhUUn_hh__ 3-30 3 CHAPTER 2. INSTALLATION Section I. f1ervice upon receipt of Direction Finder Set AN /TRD-4A______. ______31-43 36

II. Initial adjustment of equipment Uh__U n_h 44-51 52

CHAPTER 3. OPERATION Section I. Controls and instruments nh_uun_n_h______52-60 57 II. Operationunderusualconditions_huu_u_u___u__u 61-82 66 III. Operation under unusual conditions______83-86 80 CHAPTER 4. ORGANIZATIONAL MAINTENANCE Section I. Organizational tools and equipmenL _ h n _ _ n u u U U__ 87,88 81 II. Preventive maintenance_ __U_ _n_ n ______89-92 81 III. Lubrication and weatherproofing______93-95 85 IV. Troubleshooting at organizationalleveLnu_n_nn__n 96-103 86 CHAPTER 5. THEORY

Section I. Fundamental principlesn _ u _ _ _ _ h _ __ _ u _ u u _ n _ _ _ n 104-110 96 II. Block diagrams______n ______111-114 100 III. Theory of systemsnhh__n__nun__nnn_ 115-124 106 IV. Theory of Goniometer Drive MX-1170/GRDuu_un__ 125-127 116 V. Theory of Electrical Goniometers GO-5/GRD and GO-6/GRDu__m_u nnu_ 128-132 117 VI. Theory of Radio Receiver R-390 /URR_ u ___n _n __n _ 133, 134 120 VII. Theory of Azimuth Indicator IP-137/GRD__u_u__n__ 135-148 123 VIII. Theory of Radio Frequency Amplifier AM-496/TRD-4_ _ 149-156 143 IX. Theory of power and control circuitsn _ h _ u u _ _ _ u u __ 157-162 147 X. Theory of Radio Transmitter T-279/UR_uh__n_nn_ 163-167 150 CHAPTER 6. FIELD MAINTENANCE Section I. Troubleshooting at field maintenance leveL u _ n n _ n _ n 168, 169 156 II. Troubleshooting in Goniometer Drive MX-1170/GRD and Electrical Goniometers GO-5/GRD and GO-6/GRD 170-176 157 III. Troubleshooting in Azimuth Indicator IP-137/GRD_u__ 177-182 159 IV. Troubleshooting in Radio Receiver R-390/URR______183, 184 168

:::=ection V. Troubleshooting in Radio Frequency Amplifier AM-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 CHAPTER 7. SHIPMENT AND LIMITED STORAGE AND DEMOLITION TO PREVENT ENEMY USE Section I. Shipment and limited storageu h _____n ______u ___ 233-236 197 II. Demolition of materiel to prevent enemy use_ n n _n _u _ 237,238 198

J INDEx 208 1 t I CHAPTER 1

INTRODUCTION

Section I. GENERAL

1. Scope b. DA Form 468, Unsatisfactory Equipment a. This manual contains instructions for the Report, will be filled out and forwarded to the Office of the Chief Signal Officer, as prescribed installation, operation, maintenance, and repair in SR 700-45-5. of Direction Finder Set AN /TRD-4A. A typi- c. DD Form 535, Unsatisfactory Report, will calinstallation using Direction Finder Set AN / be filled out and forwarded to Commanding TRD-4A is shown in figure 1. General, Air Materiel Command, Wright-Pat- b. Forward comments on this publication to terson Air Force Base, Dayton, Ohio as pre- CommandingOfficer, The Signal Corps Publi- scribed in SR 700-45-5 and AF TO 00-35D-54. cationsAgency, Fort Monmouth, N. J., Attn: d. DA Form 11-238, Operator First Echelon StandardsDivision. Maintenance Check List for Sig~al Corps 2. Formsand Records Equipment (Radio Communication, , 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, Direction proper Shipment, will be filled out and for- Finding, Carrier, Radar) will be prepared in wardedas prescribed in SR 745-45-5 (Army) ; accordance with instructions on the back of NavyShipping Guide, Article 1850-4 (Navy);, the form (fig. 52). andAFR 71-4 (Air Force). ... f. Use other forms and records as authorized.

Section II. DESCRIPTIONAND DATA

3. Purpose and Use tools, test instruments, and field spares are a. Direction Finder Set AN /TRD-4A is a packed in bins and chests within the shelter. completetransportable radio direction finding In addition, bins, brackets, straps, and racks stationthat covers the frequency range of .54 are provided for transit stowing within the to 30megacycles(mc), with separate facilities shelter of all components of Direction Finder for direction finding, intercept reception, com- Set AN /TRD-4A except the power units. municationreception, field telephone communi- b. Flexibility to meet widely varying field cation, and frequency measurement. These conditions is pr:Jvided by three direction find- facilities are housed in Shelter S-44A/G and ing antenna systems and two basic bearing arearrangedaround three individual operating indication methods. positions,one each for a direction finder, inter- c. The direction finding antenna systems are cept, and communication operator. Special a fixed-position, four-element Adcock antenna 3 )

1. SC4 a. Tl installa of Dim cal instl TRD-4, b. Fo Comma] cations Standar

2. For The 1 porting equipme tenance : l a. DD proper 1 warded ~ Navy Sh and AFI

3. PurF a. Din complete station tl to 30 me!J for direct municati(] TM688-S2' cation, a facilities Figure 1. Direction Finder Set AN/TRD-4A. are arran: positions, cept, and 2 with a wire-mesh counterpoise, a fixed-position, tion Finder Set AN/TRD-4A is passed through crossed-, and a manually rotatable an autotransformer located in Junction Box single-loop antenna with a high-sensitivity pre- J-95B/CRD-2. Provisions for metering line amplifier. frequency and voltage and for adjusting the d. The Adcock antenna is intended for fixed line voltage to the optimum operating level of station or semifixed station direction finding on 115 volts are contained in the junction box. FIX AREI either ground waves or sky waves from nearby j. Two Gasoline Engine Generator Sets PU- SIGNAL SO or distant transmitters. Both of the loop an- 236/G, which consist of a Power Unit PU-58/G NO.1 tenna systems are usable for either mobile, in Trailer M-105, are supplied with each Direc- fixed station, or semifixed station direction find- tion Finder Set AN/TRD-4A. A power unit ing, but only on ground waves received from selector switch (in Switch Box SA-345/U) is relatively nearby transmitters. supplied. This switch has three positions, two e. The rotatable single loop and preamplifier for the power units supplied with the set and combination is intended for weak-signal ground- one for a third power unit or an outside power 1 ..~ wave applications that require high receiving line. sensitivity. RANGEOF f. The types of indication are automatic 4. Systems application BEARING UNCERT visual (using a cathode-ray tube (crt) indica- a. One direction finder set can determine OIRECTION tor) and aural-null. The visual indicator is only the bearing of a distant transmitter. Two FINDING always used with a motor-driven goniometer. or more direction finder sets must be used to Either a manually operated goniometer or the find the position or fix of a transmitter by tri- rotatable single loop is used for aural-null angulation (par. 6). Single direction finder indication. sets are sometimes used for homing of aircraft, g. Automatic visual indication has the gen- but are commonly, direction finder sets, such as DIRECTION FINDER eral advantages of high-operating speed and Direction Finder Sets AN/TRD-4A, are oper- AN/TRD-4A convenience, accuracy on swinging bearings, ated in groups or nets, and bearings from the positive sensing under all conditions and is, in individual direction finder sets are plotted on addition, more suitable for use by unskilled maps to establish the fix of a transmitter. operators. Direction finder nets usually use a minimum h. Aural-null indication is provided prima- of three sets. Figure 2 illustrates the use of Figl rily because of its advantages under conditions three direction finder sets to determine the fix of noisy reception and cochannel interference area of one transmitter and for intercept moni- 5. Basic P from other stations and also for standby use toring of a second transmitter. A line per] if the visual indicator should breakdown. The b. If direction finding could be accomplished front alway! sharpest receiver selectivity may be used with without errors, a fix would always be a definite tenna. A di aural-null indication to minimize noise and point. However, because of small and unavoid- wave front. interference. Separate and accurate bearings able bearing errors and fluctuations caused by is then assum can be obtained on several interfering trans- instrumental and propagation factors, a prac- front. For dE mitters by using aural-null indication in com- tical fix almost always is an area within which graphs 104 n bination with the receiver beat-frequency the signal source (transmitter) exists. The two oscillator (bfo). The disadvantages of aural- bearing lines drawn toward the source from 6. Definitiol null indication are less definite sensing, slowness each direction finder in figure 2 represent the This paragl and reading difficulty when bearings are swing- range of possible error or uncertainty in indi- the technical ing, and the requirement for greater operator vidual bearings. Ambiguity. skill. c. Figures 56, 57, and 58 are simplified func- either of two I i. Direction Finder Set AN/TRD-4A re- tional block diagrams of Direction Finder Set Azimuth. (: quires a single-phase 50 to 69 cycles per second AN/TRD-4A, which show the relationships of Base line. . (cps), alternating-current (ac) power source the various components to each other. Direc- tions of two d. of 2,000-watt minimum capacity and a nominal tion Finder Set AN/TRD-4A is an extremely Bearing. Tl voltage of either 115 or 230 volts. The power versatile direction finding system and the com- mitter measur source must be well-regulated and its output ponents in this set may be interconnected in direction such~ must be free from transient fluctuations. Power any of several different ways to produce opti- Direction. T; supplied to the electronic components of Direc- mum performance in all circumstances. are arriving f 4 !>ugh -- --- ~ --. Box -~ ~-~-_. line .- r the reI of ox. Pu- -58/G Direc- r unit 'U) is s, two at and power

. ermine r. Two INTERCEPTION used to by tri- I finder

Lircraft, - DIRECTION FINDER such as SET ; , TRD-4A re oper- :rom the otted on lsmitter. ninimum ,e use of Figure 2. Tactical use of direction finder sets in a net for position finding and interception. le the fix ~ptmoni- 5. Basic Principles Direct bearing. The bearing from the direc- tion finder set to the transmitter. A line perpendicular to an undistorted wave )mplished front always intersects the transmitter an- Error, instrumental. Errors in the bearing, a definite tenna. A direction finder set first locates a indicated by a direction finder set, which are !unavoid- wave front. The direction of the transmitter caused by equipment inaccuracies. caused by is then assumed to be perpendicular to the wave Error, ., Errors in the bearing s, a prac- front. For detailed information, refer to para- mdicated by a direction finder set, introduced .hin which graphs 104 through 110. by horizontally polarized components of the I. The two electrical field under certain transmission con- 6. Definitions urce from ditions. Originally called night effects because Iresent the This paragraph contains an explanation of errors are generally greatest at night. ty in indi- the technical terms used in this manual. Ambiguity. Capable of being understood in Error, propagation. Errors that arise in propagation because the waves do not travel ,lifiedfunc- either of two possible directions. over a great-circle path. Finder Set Azimuth. (See Bearing.) Error, site. Errors caused by irregularities ,ionships of Base line. A line passing through the posi- her. Direc- tions of two direction finder sets. of, and obstacles or reflectors on, the terrain around a direction finder set. 1 extremely Bearing. The direction to a distant trans- nd the com. mitter measured clockwise from a reference Fix. The position of a distant transmitter. onnected in direction such as true north or magnetic north. May be obtained by triangulation plotting of roduce opti- Direction. The course on which radio waves the bearings from two or more direction finder mces. are arriving from ,a transmitter. sets. 5 Fix area. The area within which the signal Vertical sense antenna.._A vertically polarized monopole Battery powe: originates (fig. 2 and par. 4b). provides sense voltage when transmitter Great-circle path. The shortest distance be- the single-loop antenna is Battery BJ used. tween two points, measured on the surface of 135-volt. a globe. Types of signals on which Amplitude-modulated, contin- bearings are obtained. uous-wave, or code, and fre- Battery BA Ground wave A radio wave propagated over quency-modulated. 1.5-volt. the surface of the earth. Bearing indications: Magnetic declination. The angle between Instantaneous visuaL __Bearing pattern, propeller (A, 8. Nomencll fig. 3); sense pattern, folded true north and the direction indicated by a propeller (B, fig. 3). Throughout magnetic compass. This angle varies for dif- Aural-nulL __..___h ___J'\ull in the loudspeaker output. be referred to ferent locations on the earth. It is necessary, Accuracy: common name Instrumental accuracy _Errors do not exceed 2° for therefore, to use charts or maps that show dec- N omenclatl lination and the annual change in declination. vertically polarized waves. Direction Fin( Magnetic north. The direction toward which Octantal error ______Varies with the frequency, AN /TRD-J direction of signal arrival, Goniometer D a compass needle points. and antenna installation (fig, MX-1170/< Reciprocal bearing. A bearing 1800 removed 50). Electrical Gon X umber of tubes: from the direct bearing. G0-5/GRI: Df receiver ______.. ___33. Electrical Gon Sense indication or pattern. An aural indica- Azimuth indicator _____10. G0--6/GRD Rf amplifier ______3. tion or visual pattern which can be interpreted Azimuth Indi< to distinguish between direct and reciprocal IP-137/GR bearings. b. Communication and Intercept Receivers. Radio Transm Sense signal. A radio signal added to the Frequency range_uu___0.5 to 32 mc. T-279/UR. Antennas ___U h ____Vertically polarized whips. Radio Frequel output of a bidirectional antenna to distinguish fier AM-49( between direct and reciprocal bearings. Types of signals received_Am, cw, and fm. Narrow-band fm can be monitored by de- Counterpoise Sensing. The procedure that uses the sense tuning; wide-band fm can be MX-1169/C finder portion of a direction finder set to dis- monitored, but voices will be Radio FrequeJ tinguish between direct and reciprocal bearings. badly distorted. m~sion L Sensitivity_h__hh Am signals, 3 uv; cw signals, SA-346/GR Sky wave. A radio wave that is propagated 1 uv. by reflection from the ionosphere. Sometimes Number of tubes uh33 in each receiver. called an ionospheric wave. c. Radio Transmitter. Triangulation. Determination of the position or fix of a distant transmitter by plotting bear- Frequency range______0.50 to 30 mc. ings from two or more direction finder sets a Antenna______U h _n ___Telescopic, vertically polarized known distance apart. whip. Transmitter type______Master oscillator power ampli- True north. The direction to the geographic fier (mopa). north pole. Types of signals___u___ _Cw and am (mcw). Effective rangeu u _h u _Le3s than 1 mile. 7. Technical Characteristics Modulation circuitu_ __hNegative resistance oscillator. Weight__n_h_nnnh_19 lb. (with batteries), 8 lb. a. Direction Finding Components. (without batteries). Frequency range__ __ _h _0.54 to 30 mc. Antenna systems: d. Power Input Requirements. FixedAdcockantenna__Four vertically polarized 115/230 volts, 50 to 60 cps: monopoles. Three radio receivers 510 watts. Fixed crossed-loop Two diamond-shaped loops. (170 watts each with antenna. the oven heaters off). Rotatable single-loop Part of crossed-loop (One dia- Rf amplifier__ u u _ _ u18 watts. antenna. mond-shaped loop). Azimuth indicator __u _100 watts. Phantom sense A portion of the voltage from Goniometer drive_n__ _125 watts. antenna. each monopole in the Adcock Heater n 550 watts. or from each leg in the Ventilation blower 300 watts. crossed-loop provide3 sense motor. TY voltage when using either Lighting (four 60-watt 240 watts. the Adcock or crossed-loop lamps). anteI1na. TotaL ______1 ,843 watts. 6 \. :~...

. .' .,:,,'

Nomenclature Common name >pole Battery power for radio Radio Receiver .vhen transmitter: Df receiver, intercept receiver, R-390/URR. or communication receiver. .a is Battery BA-424jU, 67.5 volts, 4 ma max. Adcock antenna. 135-volt. 90.0 volts, 20 ma max. Antenna A8-533jGR ntin- 135.0 volts, 20 ma max. (group of four). AntennaAT-297 jTRD-4 Crossed-loop antenna. I fre- Battery BA-404jU, 1.5 volts, 350 ma max. 1.5-volt. Switch Box SA-345jU ___S\vitch box. Junction Box Junction box. r (A, 8. Nomenclature Assignments J-95B jCRL' -2. >lded Electrical Equipment Electrical equipment cabinet. Throughout this manual a component may Cabinet CY-1426jU. tput. bereferred to either by its nomenclature or its Shelter S-44AjG ______Shelter. commonname as follows: Cable Payout Reel Cable payout reel. , for Nomenclature Common name RL-174jG. es. Direction Finder Set Direction finder set. Gasoline Engine Gener- Generator set. ~ncy, ANjTRD-4A. ator Set I U-236jG. rival, Goniometer Drive Goniometer drive. 9. Packaging Data I (fig, MX-1l70jGRD. Electrical Goniometer Signal goniometer or indicator (fig. 4) GO-5jGRD. goniometer. Direction Finder Set AN/TRD-4A, except Electrical Goniometer Signal goniometer. for the generator sets, is shipped with the com- G0-6jGRD. Azimuth Indicator Azimuth indicator. ponents mounted in Shelter S-44A/G. The IP-137 jGRD. entire shelter is contained in one packing case. Radio Transmitter Radio transmitter. T-279jUR. Weight Dimensions Volume (lb) Contents I. Radio Frequency Ampli- Rf amplifier. (in.) (cu. ft.) (including crate) .band fier AM-496jTRD-4. Counterpoise Counterpoise. 147 x 84 X 87 622 7,000 (3,200 Refer to table 'y de- an be MX-1169jGRD. crate). of compo- ,ill be Radio Frequency Trans- Rf switch. nents (par. mi~ion Line Switch 10). SA-346jGRD. gnals ,

uized

Lmpli-

ator. 8 lb.

TYPICAL BEARING PATTERN TYPICAL SENSE PATTERN

Figure 3. Typical bearing and sense patterns.

--- 10. Table

Com

Tripod head ada, Tube socket adar Antenna AT-297 loop). Antenna Assemhl (Adcock) conta PADDED ANTENNA Antenna Se~1 BRACKETS AT-442, HOLD DOWN BAR AT-4431 INNER SHROUD- AT-4441 HEAVY FLEXIBLE AT-4451 CORRUGATED PAPER Antenna Bas Antenna COU] Ground strap An tenna 1031 Disk 1'.1J Antenna Guy ada Guy Stal l\'ylon gl Locating con Mast Base AI Mast Base BI Mast Sections: MS-1l6-Au. MS-1l7-A__.

MS-llS-A___

Canvas bag (conta and locating pin SKID MOUNTING GASKETS Ball and socket joi .MOISTURE - VAPOR Tripod (for compa PROOF BARRIER Cable Assembly S€ CG-I097/TRD- through WI04). to signal goniom SEALI NG GASKETS Cable Assembly Se CG-I098/TRD- through W204). signal goniomete Radio Frequency CG-1078/U (2 through W404). ometer to azimut OUTER SHROUD- HEAVY FLEXIBLE Radio Frequency , CORRUGATED PAPER CG-1079/V (2 ft Azimuth indicat NOTE: goniometer. CRATE BASE EXPORT ROOF SHOWN. Radio Frequency I FOR DOMESTIC SHIPMENT CG-1079/U(8 ft BOLT USE SINGLE SHEATHING. Rf amplifier to rf Radio Frequency ( TM688-70 CG-1079/U (2 it nal goniometer to Figure 4. Packing shelter for export shipment. 8

I' -.: ~. 10. Table of Components

Reqd No. Height Width Depth Length Volume Weight Component per unit (in.) (in.) (in.) (cu. ft.) (lh.) ea.

Tripod head adapter ______h L__n n__ I~ 4~dia. ------1--- 1___ __ I~ Tube socket adapter ______3n I~ I dia. ______1______.______~oz. Antenna AT-297/TRD-4 (crossed Ln_hn I 54~ 54~ nnnn__' 54~ in. ------10~ loop). Antenna Assemhly AS-533/GR (Adcock) contains: 4 &I sparenn_l_h_h ' 2dia. ------375 in. Antenna Sections: AT-442/GR______4 & I spare 'h_nn___ I~ dia. ------100 in. ------17 AT-443/GR______4 & I sparen _n'h ___n h_ IJ{6 dia. ------100 in. ------7 AT-444/GR______n_ 4 & I sparenh_'_h h_ % dia. ------100 in. ------6

AT-445/GR__h_ _ h 4 & I spare n__h %dia. ------75 m. ------4 Antenna Base MT-865/GR____ 4 & I spare 7~ 24 24 1-_____---- 21~ Antenna coupler ______n _ __ 4 & I spare_n__ 7~ 1% dia. - __ ------1- ______1______~ Ground strapn _____h n ___h 4 & 6 spares_ _ h _ h _ nnn IJ{6 u_ 27 in. ------~ Antenna Loading: Disk MX-1168/GR______4 & I spare 1% 1% ------66 in. ------

Antenna mast container ___ 4 & I sparenn_ nh 1 30 ------120 in. ------Guy adapter h h ______4 & 6 spareS_h_ % t______2% in. ------Guy Stake GP-2______20 & 5 sparesn_ n______I~ dia. ------16 in. ------Nylon guy n_._n____ 12 & 3 spares_ n n______%;dia. ------36 ft. ------Locating pinsh ______5 & 10 spares___ lnnn__h %dia. ------10 in. ------Whipantenna contains: 2

Mast Base AB-15/GR_h_____ 2h _ n -- _nnn nh __n_ - nn- -- h _ n _ -- _n_ _

____ I I Mast Base Bracket MP-50 2__n nn__ i__h__nn n__ h_ 1 _ ~~~_ _i~~ _ _I~ ~~ ~~ ~~ ~~~ Mast Sections:

M8-116-A______------2 & I spare___ __'n ______n %dia. 39~in. n ' % M8-117-A______2 & I spare_n__, n__ IJ-32to ~ .. ------38% in. ------% dia.

_h __nn n n n _ nl __ n h_ ------M8-U8-A_ 2 & I spare_ nn'n_ ~ to VB 39% in. n~n_1 VB dia.

Canvas bag (contains guy assembly 2______.______10 dia. ------15 in. n__n_h_' % and locating pin).

Ball and socket join L _ n n n _ n n _ L _h _ __ n _nn ______-n ------% ~ia. 3~in. Tripod (for compass)n___nn___n L h ______n ___l____n __h l 5 dla. ------58 in. ------(max.) Cable Assembly Set 2 & 2 spares__ nl_ h ______-' .420 dia. ------170 ft. __n_n_n' 68 CG-IO!!7/TRD-4 (170 ft.) (WIOI through WI04). Adcock antenna to signal goniometer. a Cable Assembly Set 4 2 & I sparen__-'n__hn_-' .420 dia. nhh ' 9 ft. I _n_nn__. CG-I098/TRD-4 (9 ft.) (W201 through W204). Rf amplifier to signal goniometer.a 4_ n _nnnn _-'_ n _n _n -' .420 dia. n Radio Frequency Cable Assembly ' 2~ ft. nnn' ~ CG-I078/U (2Yz ft.) (W401 through W404). Indicator goni- ometer to azimuth indicator. Radio Frequency Cable Assembly L ______nln h n _ _ _ -' .405 dia. 1__ __ h n _ -' 34 in. ___n % CG-I079/U (2 ft. 10 in.) (W405). Azimuth indicator to indicator goniometer.

Radio Frequency Cable Assembly L___n I_h 1.405dia. Ih ' 8~ ft. _n 1 3 CG-I079/U (8 ft. 6 in.) (W205). ENT Rf amplifier to .rf switch. ~G. Radio Frequency Cable Assembly 1& 1 spare___nlh__n___J .405 dia. ______n _,2ft. ------_n' ~ CG-1079/U (2 ft.) (W501). Sig- M688.70 nal goniometer to rf switch. . Reqd No. Height Width Depth Length Volume Weight Component per unit (in.) (in.) (in.) (cu. ft.) (b1.)ea. Com

Radio Frequency Cable Assembly 1______h_ ------.405 dia. ------41 in. ------1% Coun terpoise CG-I079/U (3 ft. 5 in.) (W304A). Rf switch to df receiver. J). Canvas bag I Cord CG-409E/U (2 ft. 3 in.) L______h_ ------.420 dia. ------27 in. ------KG (W303A). Df receivcr to azimuth clamps). indicator. Goniometer DrivE Electrical Gonion Electrical Power Cable Assembly I__hh______h ------.310 dia. ------27 in. ------Electrical Gonion CX-2377/U (2 ft. 3 in.) (W302). Df receiver to azimuth indicator Whip antenna gu: speaker. Hand hammer ___ Headset______Electrical Power Cable Assembly 1 & 1 spare__ _h ------.310 dia. ------3 ft. ------% Headset cord __u CX-2378/U (3 ft.) (W301). Azimuth Indicato Azimuth indicator to sigltal goniometer. Junction Box J-91 Telegraph Key J- Electric",l Power Cable Assemhly L___h__h____------.340 dia. ------30 in. ------% CX-2379/U (2 ft. 6 in.) (W701). Desk lamp______. Rod leveL _h____ Azimuth indicator to goniometer drive. Steel tape______Layout template ( Electr.ical Power Cahle Assembly 3 & 1 spare_____ ------.640 dia. ------.- 20 ft. ------G CX-2380/U (20 ft.) (W801 Loudspeaker LS-I through W803). Three power Cable Payout Ree units to switch box. Plumb bob (for tr Electrical Power Cable Assembly L_h______------.640 dia. ------125 ft. ------30 Radio Frequency. CX-2380/U (125 ft.) (W804). AM-496/TRD- Switch box to terminal box. Radio Receiver R mounted. Electrical Power Cable Assemblx 1______.____h ------.5-10 ------8ft. ------Iff CX-2381/U (8 ft.) (W901). Junc- Radio Receiver R. tion box to azimuth indicator. Case CY -979 /UI Gasolme Engine GE Iectrical Po" er Cable Assembly Lh______------.540 dia. ------10 ft. ------1% CX-2381/U (10 ft.) (W902). PU-236/G, cont~ Power Unit PI Azimuth indicator to rf amplifier. Trailer M -105. lectrical Po" er Cable Assembly L__h______------.540 dia. ------10 ft. ---..------1% CX-2382/C (10 ft.) (W903). Shelter S--44A/G:_. Junction Lox to convenience Blackout curta out!et. Blower assembl lectrical POI'er Cable Assembly 1______------.540 dia. ------16 ft. ______h_ 2 Fire extinguish Fuel tank unit. CX-2383/1. (16 ft.) (WI001). Heater assembl Te"minaJ Lox to junction box. Hold-down bar: Jectrjcal Power Cable As!'embly L_____h______------.540 dia. ------.. 40 in. ------;!4 Hold-down bar CX-2383/L (3 ft. 4 in.) (WlO02). Te"minn.11 ox to circuit breaker. Joining cover __ Folding ladder_ ]etJ"('fi.) T',) e:- Cable Assembly 1______h____ ------.310 dia. ------9 ft. ------% CX-238 ill (\I ft.) (WI003). Loading skids_. Commun;('ation rereiver to loud- Skid rope, 1%-i Technical manu sfeaJ.e". Panel door key. '\adio ].Ieqt ency Cable Assembly 2______h______------.420 dia. ------14% ft. ------3% CG-1379/L (14 ft. 6 in. each) Screwdnver ___. (WI007A and WI008A). Whip Wrench, % incl antennas to intercept and com- Antenna mast strap munication reteivers. Counterpoise strap ~ Ladder strap and bu lectrical Equipment Cabinet L______33 20 21 ------8% 55 CY-1426/l;. Lamp tie-down straI Ground rod strap___ 'torae cabinet on shelter walL ____ L______32 12 30 ------6% 88 Power cable straph' )perator chair ______3h______32 18 19% ------90 Switch Box SA-345/ \1agnetic compass and case______L______4 4% ;!4 ------1% Radio Frequency Trs ::ontainer for guy stakes______h__ 2______------29% ------24 in. ----..----- ;!4 ::ontainer for locating pins______Lh__h______------14% ------15 in. ------Switch SA-346/GI ;!4 Instrument table_no ::ontainer for counterpoise______L______h ------65 ------164 in. ------10 ::ounterpoise MX-1169/GRD Telephone EE-8-B_. contains: L______75 ft. 75 ft. ------268 Telephone bracket__ Ground rod______5______------% dia. ------72 in. ------3 Radio Transmitter T .A set. consists of t, Note.-Thls list Is .10 of spare parts. Addlt Weight Reqd No. Height Width Depth Length Volume Weight (bl.)ea. Component per unit (in.) (in.) (in.) (cu. ft.) (lb.) ea. I'

Counterpoise clamp (inverted 42______---..------1% ------10%in. ------% J). Canvas bag (counterpoise Lm______'-_unn__110 ------15 in. ------% clamps). Goniometer Drive MX-1170/GRD. L 10% 12% 19 ------1.48 40 Electrical Goniometer GO-5/GRD. 2m_m_u 5% 4% 8% ------.]2 4% Electrical Goniometer GO-6/GRD. Lmm 5% 4% 8% ------.12 4% Whip antenna guy______2 _ n n . ______u ______~{6dia. n ______120 in. n____ .1 Handhanuner______L__nn_u u_C n u_ __ '__u_n___ 16 in. __h______3 Headset______3_n_n 3 6 'nu_____. 7 in. ______1 % Headset cord_ _n n______3_nn uh uu__ uU_n__ __u_un_ 75 in. n_ % Azimuth Indicator I P-137 /GRD ___ L u_u_ 10% 17 19 n 1.90 65 Junction Box J-95B/CRD-2___uu 1uu 147'2 15 14 _ __ n __ _u 1.76 64 Telegraph Key J-47 ______L nn___ 1% 27'2 57:1: ---1------% Desklamp_n__n __n__n _u_ ____ 2uu__u__n__ 32 37'2 5 - -1 _____ 2% Rod leveL ___ u ____n__ Lu n__n 4 % L_u____ Steeltape______1u n_ _nn '_hnn__ 620 in. Layout template chain (antenna) u_ 16% ft. _uuu___, % 6 -4u , __ __ _1______2 Loudspeaker LS-166/U ______- -_ ~~~~~~~~~~~~~~~-4mnu~ -2~--un Cable Payout Reel RL-174/Gnn__ Luu 26 24 l 19 6.80 75 Plumb bob (for tripod)______Lummnm 1% 1% dia. -u----- 3 m. I % _u n_' .81 Radio Frequency Amplifier L__mmn___ 33% 6% I 6% 88 30 AM-496/TRD-4. Radio Receiver R-390/URR, rack Lnm m.l ]0% 177.'1 82% mounted.

Radio Receiver R-390/URR with 2mm_nnml 12~ 17Ys I 21%]9 1----u----\2u____u__ 2.70 87% Case CY-979/URR. Gasolme Engine Generator Set 2______.. PU-236/G, contains: Power Unit PU-58/G______2 41 28% 69% ------47 1,586 Trailer M-105 n _____ 2 98 83 165% ------777 2,300 Shelter8-44A/G:__nn_n _u_ Lh 74 84% 139 ------503 2,127 Blackout curtain_ __- - _------L u 57 75 - 1-__ 1______4 Blowerassembly u___u_ L m 13% 12% 15 1------37 Fire extinguisher __ ___ - - - - u u _ Lu 16 5% dia. - - - __ __ - - -1- ______1______20 2 Fuel tank unit______- __ - --- Lnm__m___ 15% 17 15 3/ Heater assembly______Ln__m_m__ 35% 64 8%9 'n ~~~:~~~~__~~~~ 193 Hold-down bars______-- -- 4 ______1% dia. I __ 5% Hold-down bar extensionsn____ 4 u u__ 1% dia. ~~~~~~~_n'2 74 ___ -63%12 in. in. '_On' ~~~~__ 2 Joining cover ______L u 22% 249 - - - __ -1- ____ _.______6 Folding ladder ______- _--__ Ln 96 16% - __ ------1- ______1______- ___ 11 J,oading skids______2 ]0 10 ------127 . ~ Skid rope, 1%-inch______1______'______,______1% dia. -~~ ' ~~~ ~.' TechnicalmanuaLn __ _ u _ _ _ __ 1 Panel door key ______4 ScrewdrIVer______1 Wrench, % inch u___n___ 2 Antenna mast strap assembly ___. __ 2______u_ _ u__ _u ___ 10 dia. U _n _____ 34 in. ______~- Counterpoise strap assembly ______3 n___ _ n _n 67 in. % Ladder strap and buckle assembly __ 2 n_ 32 in. Yg 55 Lamp tie-down strap assembly ___ __ 2_u u_n_ u u 10 in. u-n !16 Ground rod strap__ _'__n ____u ____ 2 u__n___ _n___ u__ _u 12 in. J16 88 Power cable strap_ n _U ______2 n___ u_u u _u 30 in. % 90 Switch Box SA-345/U ______L m___m 7% 10 8% uu .34 7% 1% Radio Frequency Transmission Line L mmm 3Y2 3% 2% n mm___= 1Y2 ~ Switch SA-346/GRD. ~ Instrument table______l n___ 64% 113% 41% 1-----_---- 275 10 Telephone EE-8-B______L__u______10 4 ------8 in. ------10% Telephone bracket______L______8% 4% 1.___ 10% ------IX 268 Radio Transmitter T-279/UR n L______16 77.,- - -'-.------9y:!in. ------8 3 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. 11 mast insulator is built into this mast 11. Description of Adcock Antenna (figs. 5 and 6) section near the bottom. A ball at the lower end attaches the mast socket a. The Adcock antenna system consists of in the mast base. In the removable four vertical monopole antennas erected in a cylindrical antenna coupler (13, fig. square array centered over a square wire-mesh 6), located on the side of the mast counterpoise. The four monopole antennas cor- insulator above the ball, are two ter- respond to the four cardinal compass points: minating resistors and an antenna north, east, south, and west. cable connector. A rubber hood pro- b. To cover the frequency range of .54 to 10 tects the cylindrical housing. mc, the Adcock antenna system is erected with (5) Antenna Loading Disk MX-1168/GR a monopole height of 29 feet and a spacing of (5, fig. 6) consists of four 5%-foot 33 feet.between pairs (A, fig. 5). To cover the loops which are arranged symmetri- frequency range of 8 to 30 mc, a height of 22 cally about a common axis. The load- feet 4 inches and a spacing of 18 feet 10 inches ing disk is mounted to the top of are used (B, fig. 5). Antenna Section AT-445/GR. The c. Four coaxial cables, one from each mono- purpose of the loading disk is to im- pole, are individually routed to the center of prove sensitivity and to balance in the the counterpoise. From the counterpoise cen-. low-frequency range. The loading disk ter, the entire group of four cables is routed may be collapsed for shipment or stor- under and along a diagonal of the counterpoise age purposes. and then to the shelter. (6) The mast container (6, fig. 6) is pro- d. Each is a four-section vided to store the antenna sections. mast, called Antenna AS-533/GR (fig. 6). An- The nylon guys (7, fig. 6) are provided tenna AS-533/GR consists of the following: to guy the erected monopole. The guy (1) Antenna Section AT-445/GR (1, fig. adapter (8, fig. 6) is used to connect 6) is a 3J4-inch diameter, steel tube the nylon guy to the guy stake; one approximately 75 inches long. An in- spare is provided. Four Guy Stakes ternally threaded sleeve in the upper GP-2 (9, fig. 6) are used to anchor end is used to attach the antenna load- the base to the ground, and another ing disk. A locking lever at the lower Guy Stake GP-2 is used to anchor a end is used to clamp it to the section nylon guy to ground. The locating below. . pins (10, fig. 6) are used to mark the (2) Antenna Section AT-444/GR (2, fig. location for erecting the monopole. 6) is similar to Antenna Section AT- The ground strap (11, fig. 6) is used 445/GR except that it is made of a to connect the lower end of the an- 'Va-inch diameter tube approximately tenna coupler to the counterpoise. 100 inches long and has a guy plate (7) Antenna Base MT-865/GR (12, fig. fastened to the upper end. A locking 6) is a square wooden platform with lever at the lower end is used to clamp it to the section below. a socket for the mast ball. A cutaway portion of the socket allows the mast (3) Antenna Section AT-443/GR (3, fig. to be lowered to a horizontal position. 6) is similar to Antenna Section AT- There are three leveling screws on the I 444/GR except that it is made of socket for adjusting the mast verti- 1¥6-inch diameter, steel tube approxi- cally. Two pins are provided, one is mately 100 inches long and has no used to lock the ball in the socket and guy plate. A locking lever at the lower the other is used to keep the mast end is used to clamp it to the section vertical. Four guy stakes are driven below. through the holes in the corner of the B. (4) Antenna Section AT-442/GR (4, fig. base to anchor the base to the ground. 6) is a 1%,-inch diameter, steel tube Two guy plates for attaching the guys approximately 100 inches long. The are secured to the base. 12 tis mast n at the ; socket movable (13, fig. he mast two ter- antenna ood pro-

1168/GR 51f2-foot vmmetri- rhe load- e top of ;R. The is to im- :lcein the ,ding disk It or stor-

6) is pro- sections. ~provided . The guy A. LOW-FREQUENCY ANTENNA (.54-IOMC),33 F'T SPACING, FOUR SECTIONS AND LOADING DISK FOR to connect EACH MONOpOLE. !take; one uy Stakes to anchor ld another ) anchor a Ie locating ) mark the monopole. 6) is used of the an- ,erpoise. R (12, fig. tform with A cutaway I'Sthe mast tal position. rews on the mast verti- ided, one is ~socket and :p the mast ! are driven

orner of the B. HIGH-FREQUENCY ANTENNA(S-30MC), 18 FT 10 IN. SPACING, THREE SECTIONS FOR the ground. EACH MONOPOLE. TM688-56 ing the guys Figure 5. Adcock a,ntenna, insta,Uations. 13 :3 5 6

9

10

TM 688:"122 1 Antenna Section A T-445/GR 2 Antenna Section AT-444/GR 5 Antenna Loading Disk MX-1l68/GR 10 Locating pins 3 Antenna Section AT-443/GH. 6 Mast, Container . 7 Nylon guys .\: '; ..' 11 Ground strap 4 Antenna Section AT-442/GR 8 Guy adapters 12 Antenna Base MT-865/GR 9 Guy Stakes GP-2 13 Antenna coupler

14 Figure 6. Antenna AS-533/GR (Adcock monopole). c .3

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

e-. --- 0) "" I e-. 8 I 1E1IiliI:Ii_&;£¥ii

'" ...., - ,9 . " "" '" ;:!!- r I / r.",.... 12. Descriptionof Antenna 13. Descriptionof Counterpoise 14. DescriF AT-297/TRD-4 (Crossed-loop) MX-1169/GRD Asse (fig. 7) (fig. 8) (fig. The crossed-loop antenna consists of two Counterpoise MX-1l69/GRD assures uni- Two whip identical diamond-shaped loop antennas form ground conductivity for all four mono- one is used w mounted at a fixed angle of 90° with respect to poles of the Adcock antenna system. The coun- other is used each other when installed on the roof of the terpoise is a square approximately 75 feet on Each whip al shelter (C, fig. 7). The, loops, when installed, each side when unfolded. It consists of nine Sections MS- extend 4 feet 10 inches above the roof of the 75-foot by 8-foot sections of 18-inch mesh which A and Mast I shelter. The loops have hinged joints at the is constructed of No. 12 gage stranded, tinned, inch long ma~ outermost corners, permitting them to be folded copper wire. Each section has an 8-foot wooden when stowed (B, fig. 7). One loop can be re- piece at each end. The nine sections are joined moved and the other can be operated alone as to one another by strips of ~-inch tinned, cop- a rotatable antenna (A, fig. 7). The 'vertical- per braid. The counterpoise is anchored to the ground by 42 metal clamps that fit over the insulated rod at the center of the crossed-loop wooden end pieces. Four ground stakes and antenna serves as a mechanical support when the fixed crossed-loop antenna is used and one spare are provided for grounding the cor- ners of the counterpoise. When folded, the serves as a sense antenna when the rotatable single-loop antenna is used. counterpoise is protected by a canvas wrap- around container, secured by straps.

Figure 8. Unfolding Adcock antenna counterpoise. Figu ,-.16

~-_._. 14. Description of Whip Antenna and into the mast base to form a vertical an- Assemblies tenna which is 10 feet 214 inches high. Mast (fig. 9) Section MS-1l6-A is three-eighths inch in diameter. Mast Section MS-1l7-A tapers from es uni- Two whip antenna assemblies are supplied, eleven thirty-seconds inch to one-fourth inch . mono- oneis used with the intercept receiver and the in diameter, and Mast Section MS-118-A other is used with the communication receiver. le coun- tapers from seven thirty-seconds inch to one- feet on Each whip antenna assembly consists of Mast eighth inch in diameter. Mast Base AB-15/GR of nine SectionsMS-1l6-A, MS-1l7-A, and MS-1l8- has a coaxial connector for the antenna cable h which A and Mast Base AB-15/GR. The three 391/2- to the receiver. tinned, inchlong mast sections screw into one another wooden 15. Description of Radio Frequency Trans- e joined mission Line Switch SA-346/GRD led, cop- (Rf Switch) d to the (fig. 10) )ver the The radio-frequency (rf) switch is a two- kes and position switch assembly located on top of the the cor- electrical equipment cabinet (fig. 13). Its pur- led, the pose is to select the direction finder (df) re- s wrap- ceiver input either from the signal goniometer or from the rf amplifier. a. When the R.F. SWITCH is in the GONIO- METER position, the signal starts in either the Adcock or crossed-loop antenna, depending on which antenna cables have been connected to the signal goniometer. Note. The ANT. SELECT. switch on the rf ampli- fier must be placed in the CROSSED LOOP position to complete the circuit when the cables from the crossed- ) loop antenna are connected to the signal goniometer.

l I i

q

~M688-121 ! Figure 1.0. Radio Frequency Transmission J~:688-2~ .' : Figure 9. Whip antennas. .. . Line Switch SA-346/GRD. 17' b. When the rf switch is in the R.F. AM- Set AN/TRD-4A. Four additional sets of ter- 17. Descr minals are available for connecting four other PLIFIER position, the signal may start at J-~ equipments if desired. Two convenience outlets either the sense or single-loop antenna, depend- (fiJ ing on the setting of the ANT. SELECT. switch for electrical accessories are also provided. located on the rf amplifier. In the MONITOR b. At the bottom of the switch box, openings Junction position of the ANT. SELECT. switch, the for three input cables and five output cables trol and di: signal starts at the sense antenna. In the are provided and equipped with clamps. The from eithe SINGLE LOOP position of the ANT. SELECT. cable terminals connect to %6-inch screw-type commercial switch, the signal starts at the single-loop posts on two terminal boards inside the switch equipment. antenna. box. To facilitate attachment of the cables, the bp and side covers of the switch box may be 16. Description of Switch Box SA-345/U readily removed by unhooking the four spring (fig. 11) clamps. The switch knob and convenience re- u. Switch Box SA-345/U is a portable metal ceptacles are recessed into the front of the box 8% inches high, 111,4 inches wide, and 9 switch box for protection. Two handles and inches deep, which houses a heavy duty 60- two straps are provided to permit carrying ampere, two-pole, four-position rotary switch. the switch box and attaching the switch box It is used to connect the output of anyone of to a stake driven into the ground or to the side three power sources (115/230 volts, 50 to 60 of a trailer associated with the power unit cycles per second (cps» to Direction Finder (fig. 30).

Figure 11. Switch Box SA-9J,.5/U. 18 ter- transformer with an OUTPUT VOLTAGE 17. Descriptionof Junction Box ;her CONTROL for adjusting the output voltage to lets J-95BjCRD-2 115 volts when there is not more than 10-per (fig. 12) cent variation of input voltage (103 to 127 v. .ngs Junction Box J-95B/CRD-2 acts as a con- or 207-253 v.). A LINE FREQUENCY meter, bles trol and distribution point for the power fed an OUTPUT VOLTAGE meter, CIRCUIT The from either the mobile power units or a BREAKERS, LINE INPUT and OUTPUT type commercialpower source to the electronic LOAD switches are located in recessed front 'itch equipment.The junction box contains an auto- panels. Dummy load resistors, capable of dis- the 1 'f be I ring ~ re- the and ying box side unit I 1

r I TM6SS-S6 r. 1. , Figure 12. Junction Box J-95B/CRD-2.

19 sipating 4 box. ThE making p line volta it is appl 115-volt a input coni junction provided I Warn in ience outl minal box (fig. 92). 18. Desl C ( Electric a reinforl inches wi< deep. a. Open the rack p. on the Va] metal sere quate cro~ shock mou electrical f the upper tional shoe b. The I ered pane Goniomete: Indicator R-390/UR electrical e c. The r electrical e 19. Desci M; (fi a. The gj provides tb the signal ~ meter simu: which is pr of the goni(J The bearinJ null operat: goniometer "",~,~_TM..~aa-IQ6,. horsepower Figure 13. Electrical Equipment" Cabinet CY-11,26/U. components installed. a belt arrar 20

-- _.- sipating 400 watts, are provided in the junction b. The assembly mounts on a chassis 121¥I6 box. These resistors serve as a load while inches by 17%6 inches with a standard rack making preliminary adjustments to allow the mounting panel 19 inches wide by 101;2inches line voltage to be adjusted to 115 volts before high. The goniometer drive is mounted in the it is applied to the electronic equipment. One top compartment of Electrical Equipment Cabi- 115-voltac input connector and one 230-volt ac net CY-1426/U (fig. 13). Built-in slides permit input connector are provided on one side of the the unit to be pulled forward when changing junction box and five ouput connectors are the signal goniometer or when making orienta- provided on the opposite side. tion adjustments. Warning: The heater, blower, and conven- c. The unit houses the goniometer drive ience outlets must be disconnected at the ter- motor, drive assembly, bearing indicator scale, minal box when a 230-volt power source is used signal goniometer, and indicator goniometer. (fig. 92). (1) Goniometer drive motor B701 is a ¥Is-horsepower, induction-type motor 18. Description of Electrical Equipment that drives the bearing indicator scale, Cabinet CY-1426/U signal goniometer rotor, and indicator (fig. 13)- goniometer rotor. Electrical Equipment Cabinet CY-1426/U is (2) The drive assembly couples the me- a reinforced steel frame approximately 21 chanical output of the goniometer inches wide, 343;4 inches high, and 20 inches drive motor to the bearing indicator deep. scale and the goniometer rotors. a. Openings 10 by 23 inches on each side of (3) The bearing indicator scale is cali- the rack provide access to the cable connections brated in degrees and indicates the on the various chassis. Removable perforated bearing of a transmitter when the metal screens inclose the sides and allow ade- equipment is being operated in the quate cross ventilation of the cabinet. Four aural-null mode. shockmounts are secured to the bottom of the (4) Electrical Goniometer GO-5/GRD or electrical equipment cabinet. Holes located at GO-6/GRD may be used as the signal the upper rear of each side are used for addi- goniometer, depending on the fre- tional shock mounts. quency. The signal goniometer re- b. The rear of the rack is inclosed by louv- solves the signals from the antennas ered panels and two cable entrance doors. into one component which is coupled Goniometer Drive MX-1170/GRD, Azimuth to the df receiver. Indicator IP-137/GRD, and Radio Receiver (5) Electrical Goniometer GO-5/GRD is I R-390/URR (df receiver) are mounted in the used as the indicator goniometer. The i electrical equipment cabinet. indicator goniometer resolves the sig- , c. The rf switch is mounted on top of the nal from the df receiver back into two electrical equipment cabinet. components that are applied to the deflection plates of the cathode-ray 19. Descriptionof Goniometer Drive tube. The indicator goniometer is MX-1170/GRD located on the left side of the gonio- (fig. 14) meter drive unit. a. The goniometer drive is the assembly that provides the means for turning the rotors of 20. Description of Electrical Goniometers the signal goniometer and the indicator gonio- GO-S/GRD and GO-6/GRD metersimultaneously. A bearing indicator scale (fig. 15) whichis protected by a door on the front panel a. The signal and indicator goniometers are ofthe goniometer drive is calibrated in degrees. cylindrical units that are end-mounted and have The bearing indicator scale is used for aural- one flat side that serves as a back plate for null operation and is directly coupled to the connectors and a switch. Mounted on the end goniometer rotors that are driven by a ¥Is- of the rotor shaft is a cylindrical coupling with horsepowerelectric motor through a pulley and a spring-loaded plunger used to engage the a belt arrangement. rotor shaft with the goniometer drive. 21 INDICATOR GONIOMETER l

Figure 15.

control switc mounted on t cator aceom: controls the

TM688-77

Figure 14. Goniometer Drive MX-1170/GRD.

b. Internally, each signal and indicator gonio- goniometer combines the outputs of the north- meter contains two stator windings, a rotating south and east-west antennas into one signal armature with a rotor winding, and a rotary that is fed to the df receiver; the indicator transformer. In addition, there is a sens.ephas- goniometer resolves the signal back into two ing network of resistors and capacitors, and in components of proper phase and amplitude, Electrical Goniometer GO-6/GRD, an inductor. which are applied to the horizontal and vertical A sense relay, signal input and output con- deflection plates of the azimuth indicator nectors, a relay excitation connector, and a cathode-ray tube. The external appearance of SENSE PHASE switch on the backplate com- Electrical Goniometer GO-5/GRD is illustrated plete the unit. Each unit is 5% inches high in figure 15. Figures 125 and 126 are schematic by 4% inches wide by 8% inches long. diagrams for Electrical Goniometers GO-51 c. Three goniometers are provided, one high- GRD and GO-6/GRD. frequency (GO-6/GRD) and two low-frequency (GO-5/GRD) types. A low-frequency gonio- 21. Description of Azimuth Indicator meter is used as the indicator goniometer (or IP-137/GRD resolver) . Either a high- or low-frequency (fig. 16) goniometer may be used for the signal gonio- a. Azimuth Indicator IP-137/GRD consists CAPTIVE meter, depending on the frequency of the re- of a chassis 17 by 17 inches with a standard SCREW ceived signal. For signals in the range of .54 rack mounting control panel 19 inches wide by to 10 me, a low-frequency goniometer is used 10% inches high, complete with 10 tubes in- and for signals in the range of 8 to 30 me, a cluding a 5-inch cathode-ray tube. The operat- high-frequency goniometer is used. The signal ing controls, df receiver loudspeaker, power 22 components in the electrical equipment cabin~t. Additional receptacles for interconnecting the azimuth indicator, df receiver, and goniometer l drive assembly are available at the rear of the chassis. The azimuth indicator includes a self- contained regulated 275-volt B+ power supply and a -2,000-volt high-voltage power supply for 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. PTIVE REW 105). The input voltage requirements are 115 volts, 50 to 60 cps and the power consumption is 100 watts. The azimuth indicator fits into the center compartment of the electrical equip-

COUPLING TM688-21 ment cabinet (fig. 13) and is held in place by four captive screws. Handles are provided to Figure 15. Electrical Goniometer GO-5/GRD. facilitate removal of the azimuth indicator for servicing. control switches and alidade scale assembly are b. The azimuth indicator is provided with an mounted on the front panel. The azimuth indi- alidade and a lighted azimuth scale around the cator accommodates the connectors for and 5-inch cathode-ray tube. The rotatable alidade controls the applicatio.n of line power to all embodies cross hairs to facilitate reading the

A688-77

Ie north- Ie signal indicator into two nplitude, l vertical indicator ~rance of lustrated ichematic s GO-51

Cltor

) consists CAPTIVE standard SCREW s wide by tubes in- 1e operat- ar, power Figure 18. Azimuth Indicator IP-187/GRD. 23 bearings and is equipped with a light shield. for the antennas. The rf amplifier is attached The alidade assembly enables accurate bearing to the ceiling of the shelter and the antenna and sense determination from the propeller- mounting section extends above the roof. An shaped visual display. ANT. SELECT. switch built into the unit allows the loop antennas to be used for either 22. Description of Radio Receiver rotatable single-loop, aural-null operation with R-390/URR the rf amplifier, or fixed crossed-loop operation. (fig. 13) A hand wheel and an azimuth scale are pro- a. Radio Receiver R-390/URR is a 33-tube vided for manually rotating the loop during general purpose radio receiver with a self- single-loop, aural-null operation. The over-all contained power supply that operates from a dimensions of the case are approximately 22% 115-volt, 50- to 60-cps, ac power source. The inches high by 6% inches deep. operating controls, CARRIER LEVEL and b. The self-contained power supply is de- LINE LEVEL meters, PHONES jack, and an signed for operation from a 115-volt, 50- to accurate frequency indicating dial, are located 60-cps ac power source. The power consump- on the front panel. Power input and output tion is 18 watts. The output impedance of the connectors, operating and spare fuses, tube rf amplifier is 100 ohms and the frequency pullers, and pin straighteners are located on range is from .54 me to 30 me in five bands. the back panel. Radio Receiver R-390/URR is c. The antenna base consists of a rotatable composed of a main frame, front panel, back portion and a fixed portion. The rotatable por- panel, and seven subchassis. tion is connected by a shaft to a handwheel in b. The radio receiver is designed for mount- the shelter. The fixed portion is supported in ing in a 19-inch rack. Two handles are pro- a fixed position relative to the shelter roof. The vided at the outer edge of the front panel to rotatable portion contains the sockets for the facilitate withdrawal of the radio receiver from four legs of the crossed-loop antenna and for the rack or case. Three Radio Receivers R- the single-loop sense antenna. 390/URR are provided with Direction Finder Set AN/TRD-4A. One of the receivers, used 24. Description of Radio Transmitter as the df receiver, is mounted in the bottom T-279/UR compartment of the electrical equipment cabi- (fig. 18) net (fig. 13). One of the receivers, used as the intercept receiver, is provided installed in a a. Radio Transmitter T-279/UR is a self- cabinet that is mounted on top of the operating contained, battery-powered portable unit used table, to the left of the electrical equipment as a target transmitter or signal source for cabinet (23, fig. 19). The other receiver, used calibrating and checking the operation of the as the communication receiver, is provided in- direction finder equipment in the field. The stalled in a cabinet that is mounted on top of radio transmitter emits a low-power, continu- the operating table, to the right of the electrical ous-wave (cw) or modulated continuous-wave equipment cabinet (18, fig. 19). (mew) signal. For identification of the signal, c. Instructions for the installation, operation, an audio-frequency (af) tick is superimposed and maintenance of the receivers are contained on the rf signal approximately every 2 seconds. in TM 11-856, Radio Receiver R-390/URR. The radio transmitter feeds a monopole antenna mounted on the top of the radio transmitter 23. Description of Radio Frequency case. The radio transmitter normally rests on Amplifier AM-496/TRD-4 the ground during operation. (fig. 17) b. All Component parts incl,uding the bat- terie~ are ho~d in a sheet steel case. A hinged a. Radio Fr~quency Amplifier AM-:,-496/ cover on top 6f the case protects the operating TRD-4 is a three-tube prearpplifi-er used during controls that are located on the top panel. The single-loop, a;u~I-~!111operation. The case that hing~d cover is splashproofed by means of a contains the pteamplifier is a housing for the ~shaft, 'bearings, and slip rings for the crossed- rubber gasket around the edge and is equipped with a metal carrying handle. A neon lamp, loop and sense antennas and is also a mounting, which is part of the ticking circuit, is located 2~ tached ntenna If. An e unit either Inwith !ration. re pro- during over-all "-"~~", . >.~..~. !ly22% ~MP1.1FIER. A.F.' At.1-496/TRD.4 .$f.,Al"O_ O""~"_'_'Q'''''''' . stP\, (:QPI'N'l'I"" tr "I,"'~'('A' ": r "I"..~ ,O: <'t'H ..I . is de- . 50- to msump- :e of the 'equency oands. ..~ ~otatable ," ""...... ,,:. ablepor- ~.~ wheel in )Qrted in 'oaf. The ~ for the I and for

itter

is a self- unit used ;ource for ion of the field. The r, continu- luaus-wave the signal, )erimposed , 2 seconds. :>leantenna ;ransmitter Ily rests on AZIMUTH HAND SCALE WHEEL 19the bat- ~. A hinged .e operating panel. The means of a TM688-115 is equipped neon lamp, Figure 17. Radio Frequency Amplifier AM-496/TRD-4. t, is located 25 on the top panel and is used as a power on top panel. Splashproofing of the feedthrough wiring j indicator. bushing is accomplished by a rubber seal. A ual rese c. The antenna consists of five telescoping spring clip under the insulator makes contact at 35 an chromium-plated brass sections, adjustable to a with the antenna to hold it in position and breaker~ 5-foot length. The telescoped sections may be also to connect it to the transmitter circuits. ceiling h stored within the base by sliding the sections d. One 135-volt Battery BA-424/U and one and the through the insulated bushing mounted on the 1.5-volt Battery BA-404/U supply the power are plug, for the radio transmitter. The 1.5-volt A bat- e. She tery supplies the required filament power. The shelter h 135-volt B battery supplies all operating poten- panel of tials for the remaining circuits. The batteries maintain are not supplied with the radio transmitter and within tJ must be requisitioned. Directions for installing consists ( ANTEN N A the batteries are outlined in paragraph 42. fuel tank drain. 25. Description of Shelter S-44A/G (1) (figs. 19 and 20) Shelter S-44A/G is a knock down-type field and mobile shelter used to house all the equip- ment of Direction Finder Set AN/TRD-4A except the generator sets and to provide room for three operators. The outside of the shelter is 139 inches long by 74 inches square; it will fit in the cargo body of a 2¥2-ton 6x6 truck. Four tow rings, one at each lower corner, and four tie-down fittings at each upper corner are provided. The upper fittings hinge outward to keep the hold-down bars away from the shelter sides. a. Shelter. The shelter consists of a one- piece rigid floor and a one-piece top section joined by wall panels. Two doors and four windows are equipped with screens and black- out blinds; a blackout curtain is included for one door. b. Roof and Corner Sections. The roof sec- tion and four corner sections embody metal screening that forms a shield which minimizes loop errors caused by reradiation from electro- static and electromagnetic fields generated within the shelter. c. Ventilating System. The ventilating sys- tem consists of a motordriven blower (13, fig. 19) mounted in the roof section of a manually

operated blower outlet opening. Two lightproof 1 Storage ( KNURLED "riiustable louvers, equipped with removable 2 Fire extit 3 Lamp HOLD-DOWN filters, filter the intake air. 4 Electrical CY-142 SCREW 5 Radio Frl d. Shelter Electrical System. Two raceways Switch 6 Goniomet, !----- with 16 receptacles for U5-volt, 60-cps, ac 7 Electrical service are provided on the shelter ceiling. 8 Electrical TM688-31 9 Azimuth] These receptacles comprise 12-plug receptacles 10 Loudsveal Figure 18. Radio Transmitter T-279/UR. and four midget twist-lock receptacles. The

26 idthrough wiring for the raceway terminates in two man- heater is rated to deliver 60,000 Brit- r seal. A ual reset-type overload circuit breakers rated ish thermal units per hour. The over- ~scontact at 35 amperes, 120 to 240 volts ac. The circuit all dimensions of the heater cabinet ition and breakers (28, fig. 19) are located near the are approximately 28 inches high, 11 circuits. ceilingin a junction box. The ventilating blower inches deep, and 2414 inches long. J and one and the heater, both operating on 115 volts, Outside air may be drawn in through the power are plugged into the nearest ceiling receptacle. the louver in the shelter wall or inside olt A bat- e. Shelte1' Heater Unit (16, fig. 19). The air may be drawn through the grill )wer. The shelter heater unit is mounted on a modified end in front of the cabinet near the top ing poten- panel of the shelter. The heater is used to and warm air discharged at the front ~batteries maintain a comfortable working temperature of the cabinet near the floor. mitter and within the shelter in cold weather. The unit (2) The unit can also be used for ventila- . installing consists of a heater, inlet louver, exhaust pipe, tion in which case only the heater 3.ph42. fuel tank, fuel line, fuel drain, and water trap ventilating fan motor is in operation. drain. (3) The heater is fully described in the (1) The heating unit is a gasoline-burning, manual shipped with the heater. "'/G electrically operated space heater. The f. Loading Skids (13, fig. 20). The tW0 heater operates from a 115-volt, 50- loading skids are made of high-tensile steel. a-type field to 60-cps, ac power source. The Each skid has a hook at one end to secure the . the equip- ~/TRD-4A ovide room the shelter .are; it will 6x6 truck. corner, and , corner are outward to 1the shelter

s of a one- top section rs and four .s and black- included for

rhe roof sec- I nbody metal ~hminimizes from electro- ls generated

ntilating sys- )wer (13, fig. )f a manually TME:8S-IIO wo lightproof Storage cabinet 11 Desk lamp 21 Ladder Fire extinguisher 12 Radio Transmitter T-279/UR 22 Operating table th removable Lamp (stowed) 23 Intercept receiver Electrical Equipment Cabinet 13 Blower 24 Cable Payout Reel RL--I74/G CY-1426/U 14 Antenna Base MT-865/GR (stowed) ( stowed) Radio Frequency Transmission Line 15 Junction Box J-95B/CRD-2 25 Cable Assembly Set CG-I097/TRD-4 Tworaceways Switch SA-346/GRD 16 Heater (2 sets) 6 Goniometer Drive MX-1170/GRD 17 Operator's chair 26 Electrical Power Cable Assembly It, 60-cps, ac 7 Electrical Goniometer GO-5/GRD 18 Communication receiver CX-2380/U 8 Electrical Goniometer GO-6/GRD 19 Df receiver 27 Terminal box aelter ceiling. 9 Azimuth Indicator IP-137/GRD 20 Ladder strap and buckle assembly 28 Circuit breaker ug receptacles 10 Loudspeaker LS-166/U eptacles. The Figure 19. Location of equipment in shelter, left side. 27 skid to the tailgate hinge pin of a 21f2-ton 6 x 6 justable hold-down bars are provided to secure 26. Descri the shelter when it is mounted on or while it cargo truck. . a. Gener

It). This I IIlitI electrically 16 of 170 fee1 I 13A/U witt on each en( consists of . W103 and spares. e. Cable It). This I ~5 14 13 12 10, II 3,4,5,6,7,8 electrically TM688-I09 of 9 feet of 1 Convenience outlets Antenna Section AT-442/GR 12 Ground rods (5 ea stowed) 2 Radio Frequency Amplifier (5 ea stowed) 13 Loading skids (2 ea) with Radio AM-496/TRD-4 7 Antenna Loading Disk MX-1168/GR 14 Hold-down bars (4 ea) end. Three 3 Antenna Section AT-445/GR (5 ea stowed) 15 Hold-down bar extensions (4 ea) (5 ea stowed) 8 Antenna mast container (5 ea) 16 Antenna AT-297/TRD-4 (stowed) of W201 ar 4 Antenna Section AT-444/GR 9 Blackout curtain 17 Antenna Base MT-865/GR (5 ea stowed) 10 Counterpoise MX-1169/GRD (4 ea stowed) 5 Antenna Section AT-443/GR (stowed) and W204, (5 ea stowed) 11 Counterpoise container (stowed) I. Radio Figure 20. Location of equipment in shelter, right side. 1379/U (14 28 sists of 14 feet 6 inches of Radio Frequency !cure 26. Description of Cords and Cables He it a. General. Most of the cords and cables Cable RG-13A/U with Plug PL-259/U at one end and a Plug Connector UG-573/U at the :argo supplied with Direction Finder Set AN/TRD- a tie- other end. Two of these cable assemblies 4A are permanently installed in the shelter, other several external cables are contained in Cable (W1007A and W1008A) are provided. truck. g. CQ1'dCG-409E/U (2 ft 3 in.). This cord Payout Reel RL-174/U (fig. 21), and the spa e consists of 2 feet 3 inches of Radio Frequency ms of cablesare stowed in the storage bins under the .s (15, Cable RG-58C/U with a Radio Frequency Plug operating table. The cable check chart (par. UG-88C/U at each end. One of these cords lar by 43) lists the function of each cable and indi- cates in the Remarks column whether the cable (W303A) is provided. h. Electrical Power Cable Assembly CX- ms for is normally installed or contained in the cable mce of 2377/ U (2 ft 8 in.). This cable assembly con- payout reel. sists of 2 feet 3 inches of two-conductor cable I, Shel- b. Radio Frequency Cable Asser.~bly CG- with a female plug #AN-3108A-14S-9S on l of the l078/U (2 ft 6 in.). This cable assembly con- one end and two soldering lugs on the other figures sists of 2 feet 6 inches of Radio Frequency end. One of these cable assemblies (W302) is CableRG-13A/U with a Radio Frequency Plug UG-21B/U on each end. Four of these cable provided. i. Electrical Power Cable Assembly CX- 9 assemblies (W401), W402, W403, and W404) I 2378/U (3 ft). This cable assembly consists are provided. of 3 feet of 2-conductor cable with a female c. Radio Frequency Cable Assembly CG- l079/U. This cable assembly consists of Radio plug #AN-3106A-12S-3S on one end and a male plug #AN-3108A-12S-3P on the other Frequency Cable RG-22B/U with a Plug C:m- end. Two of these cable assemblies (W301 and nector UG/421-U on each end. Five of these one sp'ilre) are provided. cableassemblies are provided and distinguished j. Electrical Powe1' Cable Assembly CX- by different lengths. 2379/U (2 ft 6 in.). This cable assembly con- (1) One 8-foot 6-inch cable assembly sists of 2 feet 6 inches of four conductor cable (W205) is provided. with a female plug #AN-3106A-14S-5S on (2) One 2-foot lO-inch cable assembly one end and a male plug #AN-3108A-14S-5P (W405) is provided. on the other end. One of these cable assemblies (3) Two 2-foot cable assemblies (W501 (W701) is provided. and one spare) are provided. -k. Electrical Power Cable Assembly CX- (4) One 3-foot 5-inch cable assembly 2380/U (20 ft). This cable assembly consists (W304A) is provided. of 20 feet of two-conductor cable with two ter- d. CableAssembly Set CG-l 097/T RD-4 (170 minal lugs on each end. Four of these cable It). This cable assembly set consists of two assemblies (W801, W802, W803, and one spare) electricallymatched cables. Each cable consists are provided. _ of 170 feet of Radio Frequency Cable RG- l. Electrical Power Cable Assembly CX- 13AlU with Radio Frequency Plug UG-21B/U 2381/U (.ft). This cable assembly consists on each end. Four sets are provided, one set of two-conductor cable with a Harvey Hubbell consistsof W101 and W102, one set consists of connector No. 7238 at one end and a Harvey W103and W104, and the other two sets are Hubbell connector No. 7224 at the other end. spares. Two of these cable assemblies are provided, one e. Cable Assembly Set CG-l098/TRD-4 (9 (W901) is 8 feet and the other (W902) is 10 ft). This cable assembly set consists of two feet long. .\,II 3,4,5,6,7,8 electricallymatched cables. Each cable consists m. Electrical Power Cable Assembly CX- TM688-I09 of 9 feet of Radio Frequency Cable RG-13A/U 2382/U (10 ft). This cable assembly consists stowed) with RadioFrequency Plug UB-21B/U on each l) of a two-conductor cable with a Harvey Hubbell ea) connector No. 7224 on one end and two ter- enslons (4 ea) end. Three sets are provided, one set consists 'RD-4 (stowed) of W201and W202,one set consists of W203 -865/GR minallugs on the other end. One of these cable andW204,and the other set is a spare. assemblies (W903) is provided. /. Radio Frequency Cable Assembly CG- n. Electrical Power Cable Assembly CX- l379lU (14 ft 6 in.). This cable assembly con- 2383/U ( ft in.). This cable assembly con- 29 sists of two-conductor cable with a Harvey the compass to orient the Adcock antenna with standby unit Hubbell connector No. 7224 on one end and two true or magnetic north during installation. the third is i terminal lugs on the other end. Two of these c. Operator's Chairs (17, fig. 19). Three Set PU-236/' cable assemblies are provided, one which is 16 office-type chairs for the operators are fur- Unit PU-58/ feet long and is used as W1001 and the other nished with Direction Finder Set AN/TRD-4A. power unit which is 3 feet 4 inches long and is used as d. Cable Payout Reel RL-174/G (fig. 21). 60-cps, singl W1002. The cable payout reel supplied with Direction capacity is 5 o. Electrical Power Cable Assembly CX- Finder Set AN/TRD-4A is a cable reel mounted 6.25 kilovolt- 2384/U (9 It). This cable assembly consists in its own transport case. The cable payout tor. Refer 1 of 9 feet of two-conductor cable with terminal reel facilitates laying and rewinding of the 58/G, for de lugs on one end and the other end is unproc- main power cable and Adcock antenna cables. i. Othe1' ( essed. One of these cable assemblies is provided e. Storage Cabinet (1, fig. 19). A storage parts descrit and used as W1003. cabinet with three drawers is provided on one Finder Set 1 end wall of the shelter. The equipment stored fuses and lar in these drawers is as follows: stake adapte (1) The equipment stored in the bottom container, gl drawer is illustrated in figure 22. 166/U. (2) The equipment stored in the middle 28. Runnil drawer is as follows: Note: The (a) Receiver spares (par. 28e) are also listed (b) Radio transmitter spares (par. 28b) a. Azimut (c) Headsets and cords (2 and 3, fig. 25) Spare V (d) Telegraph key (11, fig. 25) 1 t (e) Special tools kit (4, fig. 25) (3) The equipment stored in the top drawer 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 of the major components of the direction finder set mount on a pipe frame table secured to the shelter floor. The operating table includes stor- age bins underneath and an armrest along the front, with lift-up doors and storage spaces inside. These storage spaces and their contents I3J are listed in (1), (2), and (3) below: (1) Contents of the left side of the storage bin are shown in figure 23. (2) Contents of the right side of the stor- age bin are shown in figure 24. 14~ (3) Items of equipment stored in the arm- rest and middle drawer of the storage ~ bin are shown in figure 25. 15 ~/fJ Figure 21. Cable Payout Reel RX-174/G. g. Tools. A set of tools for installing and repairing the direction finder set is included 27. Description of Minor Components with the equipment (par. 88). a. Compass (fig. 27). For orienting the Ad- h. Gasoline Engine Generator Set PU-236/G. cock antenna and the loop antennas during Two generator sets are supplied as part of 1 Switch Bo: installation, a compass, a ball and socket, and Direction Finder Set AN/TRD-4A. Up to 2 CompaSs c 3 Compass an adapter are furnished. three generator sets may be used alternately 4 Ban and s b. Tripod (7, fig. 24). A tripod is used with in 8-hour shifts. Three generators allow one 30 nna with ation. Three are fur- rRD-4A. (fig. 21). Direction mounted le payout g of the la cables. \. storage ~d on one mt stored

Ie

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

:par.28a) 28c) par. 28d) Most of ion finder red to the udes stor- along the ge spaces r contents

f the stor- 24. n the arm- he storage

>U-236/G. .s part of \.. Up to 'tlternately allow one '1

Z i 15------

3 12

14 - 4 11 13

IZ ... ::i:¥:"8 " -- - - - 5

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

10 9 e 7

1 Electrical Power Cable Assembly 6 Counterpoise clamps 1 Cable As! 11 Bag for locating pins and layout (170 ft CX-2380/U (20 ft) 7 Locating pins and container template 2 Guy stakes and container 12 cables' 3 Hammer 8 Layout template chain Gag for g-uys 2 Mast Bas 9 Guy stake adapter 13 Telephone mounting bracket 4 Bag for counterpoise clamps 10 Nylon guys 14 :I Mast Bas Telephone EE-8-B 4 Mast Sec. 5 Grounding straps 15 Skid rope 1'4 -inch (100 ft) Figure 23. Contents of storage bin, left side.

c. Rf Amplifier Spares. 3 type 6BJ6 pentodes. Spare tubes. 6 type 6C4W triodes. 1 type 6AU6 pentode. 1 type 12AT7 dual triode. g. Shelter 1 type 6X4W rectifier. 3 type 12AU7 dual triodes. 3 keys. Spare dial lamps. 1 type 26Z5W rectifier. 3 cord i 2 Lamps LM-52. 1 type 5651 voltage regulator. 10 panel Spare fuses. 4 type 5749 6BA6W pentodes. h. Adcock 6 Bussman type AGC %-ampere 1 type 6082 dual triode. 1 Anter fuses. Spare fuses. 1 Anter d. Goniometer Drive Spares. 6 type 3AG 3-ampere fuses. 1 Anter Spare lamp. 6 type 3AG %-ampere fuses. 1 Anter Spare dial lamps. 1 Lamp LM-52. 1 Anter 4 type GE 327 lamps. e. Receiver Spares. f. Heater Spares. 1 anten Spare tubes. 1 type AG6-12 volt spare plug. 6 grOUIJ 2 type 3TF7 voltage regulators. 1 type XEJ-14-2 electrode. 1 Anter 6 type 6AJ5 pentodes. 1 electrode gasket. 1 anten 2 type 6AK6 pentodes. 1 tank gasket. 6 guy 2 1 type 6BH6 pentode. 1 hmk fitting. 5 Guy: 32 ,..-z ,

I

I , , , ~

I

I

,

10 9 8 7 1688-139 TM688'1~~ j Cable Assembly Set CG-1097/TRD-4 5 Mast Sections MS-117-A 10 Cable Assembly Set CG-1098/TRD-4 ).out (170 ft) (a set consists of two 6 Mast Sections MS-116-A (9 ft) (a set consists of two cables electrically matched) 7 Tripod with adapter and cap cables electrically matched) 2 Mast Base Brackets MP-50 8 Electrical Power Cable Assembly 11 Shelter joining cover 3 Mast Bases AB-15/GR C7-2378/U (3 ft) 12 Electrical Power Cable Asse~bly . Mast Sections MS-118-A 9 Radio Frequenc). Cable Assembly CX-2380/U (20 ft) CG-1079/U (2 ft)

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

g. Shelter Spares (Stowed in Floor Cavity). 3 nylon guys. 3 keys. 10 locating pins. 3 cord grip caps. i. Whip Antenna Spares. '. 10 panel fasteners. 1 Mast Section MS-116-A. I, 1 Mast Section MS-117-A. h. Adcock Antenna Spares. 1 Antenna Section AT-442/GR. 1 Mast Section MS-118-A. 1 Antenna Section AT-443/GR. j. Spare Cables. 2 Cable Assembly Sets CG-1097/TRD-4 1 Antenna Section AT-444/GR. (170 ft). 1 Antenna Section AT-445/GR. 1 Cable Assembly Set CG-1098/TRD-4 1 Antenna Base MT-865/GR. (9 £1). 1 antenna coupler. 1 Radio Frequency Cable Assembly 6 ground straps. CG-1079/U (2 ft). 1 Antenna Loading Disk MX-1168/GR. 1 Electrical Power Cable Assembly 1 antenna mast container. CX-2378/U (3 ft). 6 guy adapters. 1 Electrical Power Cable Assembly 5 Guy Stakes GP-2. CX-2380/U (20 ft). 33 29. Addition Not S Batteries ar Radio Transmi nished with thE be requisitione 1 Battery 2 high 1 1 Battery high'

8 j 1- I 6 --. . . 'j J .-..------TM668-123 1 Literature 5 Steel tape, 50-foot 9 AJlnement tools 13 Test cable, rf amplifier 2 Cords for headset 6 Allen wrenches 10 Antistatic wax 3 Headsets 7 Tube adapters 11 Telegraph Key J-47 4 Special tool kit ba~ 8 Tube extractor 12 Screwdrivers Figure 25. Contents of armrest and storage cabinet, middle drawer. I ,/

2 ,/

4 ,/