AN/ARC-34 Made in 1952 by RCA and Magnavox

Transcription

1 /- ade in by and agnavox everse engineered drawings may contain errors. heck my internet site for updates:

2 - ystem wiring + dc volume -0 / control eadset or intercom lamps O G. ush-to talk ransmit igit igit igit igit tone Guard-on ain-on + econd plug on -0 or -0 n k f h j p m s r ike bias emote requency Indicator I- or I Wideband out - / - transceiver + ain G ain G quelched quelched e Z r W X Y d utomatic irection inder - (option) etransfer option W a e k r Y c h n X b f m s Z d j p += ot connected udio signal upply voltage outputs

3 Y-0 olts x x 0 0m m Ω +00 0u k 0 e Z / tone s m r 0 0 guard tone p u odulator 0 0 bias 0 ike 0Ω OO 0 k f h j + k Gain + Oscillators & mechanical ixers rystal eference Guard eceiver 0 Gain k oax ain connector X odule stab d.err 0 side tone elector otor control 0 motor 0 + wr mpl I and udio mplifiers + main guard ux out W Y d quelch mute 0 spare ransmit hassis Wiring --0 kb n ush to talk 0Ω

4 - requency control requency control of the - is done in steps. here is a motor which tunes a voltage controlled oscillator and all and resonant circuits by variable capacitors via a gearbox. econd, the O frequency is locked to a crystal reference, set up using edex stepper motors and a relay, all controlled by the digits on the remote frequency control panel. requency is controlled in digits, in 0. z steps. he crystal reference system has oscillators. he st and nd digit select a harmonic of an. kz crystal oscillator (osc.) he d and th digit control a bank of + + = crystals, for x x = frequencies, using oscillators : osc, osc and osc. he crystals are in ovens. he crystal frequencies are. stepsize / osc. controlled by d digit stepsize /. W. osc. controlled by. X.00 combined d and th digit..000 Y. with 0kz channels has also Xtalls WXY that are 0kz/ higher.0 stepsize /0. osc. controlled by th digit..0. he lowest frequency is + + =.0 at dial xx0.0 he highest frequency is + + =. at dial xx.. kz Osc. rystal eference d digit Osc. st digit x0 x X X nd digit st mixer nd mixer - z O x + x O to receiver. z x transmit d & th digit Osc. th digit Osc. X discr d mixer derr elector he lowest xmit frequency is (.0 + x 0. ) x +. = 00.0 z he highest xmit frequency is (. + x 0. ) x +. =. z he first 0 channels are below the military band of.0. z and result in continuous running of the tuning motor.

5 ixers he first mixer compares the O frequency with the oscillator frequency his gives a first intermediate frequency of.0 -. z. ( first digit=) or when the first digit = he second mixer compares this with the osc. frequency plus. z when the first digit = his gives a second intermediate frequency of. -. z he third mixer compares this with the oscillator frequency his gives a third intermediate frequency of. -. z inally, this signal is compared with the signal from oscillator in a phase detector, resulting in zero z when locked. his is the d err signal. ote derr= 0 occurs also without O signal or large mistuning. herefore, derr= was chosen as the normal value. With kz difference, the output of the phase comparator is a kz sinewave of approx. 0 pp he first (fixed) I in the main receiver is at. z. (.0 for the guard receiver) Guard,- and main I have a common.0 z oscillator to step down to the second I frequency at. z for the main receiver, or.0 z for the guard receiver. he frequency of the O (black), and that of osc. (red) are shown in this plot, with the control panel dial setting on the X-axis. ll values are in z O djustments. he intermediate frequency filters are factory tuned inside a hermetic seal. se of derr he output of the rystal eference ystem, derror, is fed to ) the motor controller (elector), which does the coarse tuning of the master oscillator and all doubler and tripler circuits,. he motor stops when derr = ) and to a reactance tube, which phase-locks the master oscillator to the.

6 uning control ee drawing of the elector ( - / - ) ormally, when tuned, relay is O, (via its holding contact and the positive derr voltage) and the motor does not run. fter a change in selected frequency, derr drops to zero, drops O, and the motor starts running. he variable capacitors are tuned at a speed of z/sec (!) until they are in the right segment, and a negative peak occurs in derr, indicating that the correct frequency was passed. his triggers the thyratrons, and a coil selects low (0.%) reverse gear, so the variable capacitors move backward slowly. he motor itself runs still in forward direction, so the phase detector remains active. he current in the low gear coil sets O, and when the phase lock loop closes, derr becomes positive to compensate for the still slowly moving tuning capacitors. When derr reaches +, turns on and the motor stops. fter 0. sec, drops O, so the thyratrons stop conduction, but remains O to keep the motor off. In this plot, the anode voltage of thyratrons is recorded together with the derr signal. very time the tuning passes the right (0 wide) segment, the anode voltage is +00. ed is the tuned frequency, cycling between 0 and 00 z. he timebase is sec/div. otal tuning takes approx. sec. he phase lock detector is only operative with decreasing frequency, he variable capacitors shafts run at 0 rpm in coarse mode and -0. rpm in fine mode.

7 -/- ube layout --0 kb. odulator - / - estconnector = brown (,, ) 0 00 (,, ) 0 00 (,, ) 0 preamp limiter 0 splitter 0 drivers 00 = QW = 0 rame Y-/- incl dynamotor and main plug ynamotor Y0 input 0 max Output 0 m 0 0 m or at x 0 m or at x 00-0 m. ual I strip - /- estconnector = red dual diode,, 0 0 lang lus subunit with is tubes filament, otherwise identical to Oscillators X- / - estconnector = orange Z0 first osc Z0 mix Z0 mix 0 Z0 discr Z0 mix 0 lus subunits 0 is tubes in this module module - / - ocal osc. train river estconn = yellow estconn = green 0 bal. mixer 0 osc. bal.mixer 0 doubler driver 0 doubler driver 0 osc. pwr dual triode as series stab neon ref and agnavox final ampl - / - estcon = pink estconn=blue ower mpl eceiver 0 pencil 0 pencil 0 mixer 0 tripler first I Guard eceiver - / - estconn = grey mixer 0 first I 0 butler osc. 0 butler osc. 0 elector - / - estconnector = white - ( ) ontrol panel -0 / - o tubes emote indicator I- transistors. odulator. ual I strip Oscillator a ocal osc train b driver + -stab. a final b ain receiver Guard receiver 0 elector otal tubes

8 O -0 (-pin) to I-/ 0 -pin to - z 0 z z 0. z O I or O 0 O ll resistor arrays x 0 Ω I O O 0k log G Ω + G ck X X Wht X X 0 X X X X X X X X X X X X X X X X X X X X 0 z z z 0 0. z G O IIO I /? G ot used ) --G, -poition switch, has sections ontrol head -0/ - (agnavox) 0 nov 0 kb (also -/)?

9 0 delay p ike in 0 Ω + one on 0.u 0 k 0.u 0.u 0 k 0 0 k k k 0k 0 0 k 0.u ? z oscillator k 0 0 n n k n n 0 k k 0k 0k k n 0k k 0k n 0 0.u k 0.u 0p k 0 0 n k 0 0 k 0k k k 0k 0 n +0 0 Gain +00 k imiter 0k level + 00k n n 0k 0. eaters o wideband input not original, but helps to start oscillator icrophone input bandwidth z exagonal testconnector odule connector ain chassis connector estconnector olor = brown not connected ground 0. - / -. odulator - / - /0/0 kb 0u n ike ias

10 rom ain head. z rom Guard head.0 z 0k k k k.0 z.0 z 0p p p k Z0 Z 0.u 0 Z Z0 0 k k k + k ain I. z 0p 0 Guard I z k k 0 0 W ront-end G ain connector contact his module connector contact ex estconnector contacts -- testpoints k estconnector olor = red not connected ground 0 ront-end G 0k 0k 0 X 0.u 0 k k k k k 0.u 0.u +b 0.u +b k k 0.u 0.u 0k 0 0k 0k 0k n 0n 0k 0n 0n 0k 0k 0n 0k 0n 0k p 0k n Y k 0n k - / - k 00k GI 0n 0n 0n k d 0 k k 0p n k squelch k u 0k n n ilaments. I strip - / - /0/0 kb 0k k k u k ute at tuning ide tone +

11 antenna k 0k + O sample derr + x k 0 eactance tube -00 z Oscillator encil tubes 0 k 0 0 stab k k 0 doubler p k. z 0 0 to receiver local oscillator k 0 0 doubler k 0n - z - z - z 0k 0k k 0k k 0n k k 0 idestep oscillator k p. z 0n 0n k Z + x 0 0 k alanced mixer 0- z 0k 0k 0k 0k tripler O signal -z k Z 0 - z - z connector connector 0 k 0k k k to I ampl. 0k gain 0 k 0 0 0k 0 k z steps code k k k 0k x +00 k eversed low gear + 0. uto-reverse at endstops 0 0 k k k k 0 k k 0 0 k. odule --0 kb + stab 0 k 0k k k

12 O sample Ω 0 Ω Ω Ω Ω k 0 heaters + n 0 0 osc. + 0k ovens kz Ω 0 max Ω st mixer 0 0k Z stab. 0 k irst digit Grounded= Open =, +0 stab + Ω + nd mixer d mixer k Z0. z. z Z0 ink to mixer part estpoint connector in on 0 in on 0 ain connector k. z k 0 k 0k. z Z0 elay 0 + raw 0k not used X- / - discriminator 0 0 0n k 0 0 0n 0k 0 0 pp Inhibit during return cycle pp 0 0 st digit + 00k n 0k 0k pp n 00k d error + Ω Ω Ω 0 edex stepper motor 0 Ω econd digit 0 z steps x 0Ω Osc. 0k p k p k hird digit z steps Ω Ω 0 Ω edex stepper motor 0 x 0Ω 0 Osc. 0k p k p k.0000 z Ω Ω ourth digit 0. z steps 0 Ω edex stepper motor 0 0 x 0Ω Osc. 0k p k p k.0 z g osc. osc. osc. osc. h ll relay coils 0Ω j. X- / - rystal eference ystem / /0 kb

13 ntenna + rom transmitte / switch 0 Ω o main receiver p z 0 k 0 0 0p 0 k Z0 0p 0 0p k x =. z 0 z k 0.0 z estconnector olor = gray not connected ground Z0 to I ampl z k 0k k k 0 0 Ω ulova oven 0 utler.o. k k 0 mixer Z0 0 0 k GI - / -. Guard eceiver

14 +00 irst digit ixer odule 0 econd digit 0 0 k k sectors of 0 z each k 0k u n 0 k k 0k odule ariable capacitors shafts 0 uning motor low gearbox k uto reverse at endstops 0 brake - 0 Inhibit during reverse cycle 0 udio mute estconnector olor = white not connected ground + + stab d err -0 0k 0k 0n 0k 0. 0k eaters - / - + On testconnector 0. uning control ( elector ) - / - //0 kb

15 ckt x 0 odulator 0 I & udio 0 Guard 0 ixers mechanical 0 Oscillators +00 bias tone igit + + gain gain sidetone ike Guard squelch main squelch G guard wr_up x Y d X W +00 G main d err igit wr_up guard x elector 0 f h j k igit igit derr + stab. p + audio / Gnd ain plug ohm + (spare) x mute +

16 ulova oven Ω oscillators Ω mixers Ω Ω Ω Ω Ω rystal eference odulator 0. 0m I and udio Ω 0 ulova oven encil tubes encil tubes Guard x encil tubes module. uning control 0. otal filaments. x = W verage ovens. x = W

17 - input current nov 0 Input current from.dc source ilaments. Ovens ( peak ), on average :. Internal fan. ynamotor loss ). ynamotor load x/ x ). /. elays 0. / 0. uning voltage dividers (incl control) 0. otal. /. W / W ( for 0W output ) he tuning motor adds 0. during sec after any frequency change ) ynamotor input current without load. Is about at any input voltage uring run-up the input current is ) ynamotor input current portion due to load, transformed to primary current ynamotor Y0 input 0 max Output 0 m or at x 0 m 0 0 m or at x 00-0 m + =. W + = W output o load dynamotor input current in I in. easured total input current and dynamotor voltages ower supply used: dc with 0 current limit. an disconnected, otherwise complete. - ynamotor run-up with supply in current limit takes seconds. - hen current decreases to. - t 0 sec from turn-on, relay 0 turns on the 00 distribution and the tuning motor. - Input current rises to., with still running tuning motor. and fluctuations up to. due to crystal oven heaters. - With ovens hot, the current decrease to., with every sec a surge when the tuning motor reverses. t lock, the current fluctuates between 0 and. (without fan) upply voltages +0, + and + (stabilized) ll O.

18 - estpoints ach module of the /- has a special -pole test connector to check the + voltages, filament voltage, and oscillator negative grid voltages. hese are measured with the - voltmeter for a quick go/no-go test on each module. he test connectors are color coded. he voltmeter has a -position switch to measure the voltage on a pin of the test connector versus the centre pin of the test connector which is grounded in each module. I measured the following voltages on a healthy set with dc input using a with 0 input impedance. odule odulator modulated 00 x I mplifier rystal eference aster oscillator river ain eceiver ower mp Guard x elector guard x (+0 stab) + Input stab + + (+0 stab) x/ modulated + 0 gear/clutch ee plot + x + x +. + guard + (+0 stab) O- -. osc -0. idestep mixer -. osc butler -.0 osc. -0. doubler -. river -0. mixer -.0 driver he grey positions are not connected in that module. he blue positions shall be checked in ransmit mode ( key down) he guard positions shall be checked with the mode switch on the control panel in the position oth -. osc -0. doubler -0. river -0.0 tripler -. tripler odulator test points and have a series resistor, so measure 0 on a voltmeter with 0 Ω input impedance. elector test point has also series resistor, add 0% when measuring with a x0 probe any test points in the driver or ower mp have series resistor. dd 0%. he readings for the oscillators in the crystal reference module are quite independent of the frequency selected.

19 /- / - adio estset testplug for any connector in - O meter shorted meter shorted -. -, O 0 0 pos, 0 ll 00 ranges k 00k k probe ± 0. pos,, 0 u 00 Ω - 00 ll 0 ranges + 00 Ω k x 0u = 0. - /