TM 11-5820-670-30 TECHNICAL MANUAL AVIATION INTERMEDIATE MAINTENANCE MANUAL RADIO SET AN/ARC-131 (NSN 5821-00-937-4686) HEADQUARTERS, DEPARTMENT OF THE ARMY 13 SEPTEMBER 1985
TM 11-5820-670-30 SAFETY STEPS TO FOLLOW IF SOMEONE IS THE VICTIM OF ELECTRICAL SHOCK DO NOT TRY TO PULL OR GRAB THE INDIVIDUAL IF POSSIBLE, TURN OFF THE ELECTRICAL POWER IF YOU CANNOT TURN OFF THE ELECTRICAL POWER, PULL, PUSH, OR LIFT THE PERSON TO SAFETY USING A WOODEN POLE OR A ROPE OR SOME OTHER INSULATING MATERIAL SEND FOR HELP AS SOON AS POSSIBLE AFTER THE INJURED PERSON IS FREE OF CONTACT WITH THE SOURCE OF ELECTRICAL SHOCK, MOVE THE PERSON A SHORT DISTANCE AWAY AND IMMEDIATELY START ARTIFICIAL
TM 11-5820-670-30 HIGH VOLTAGE is used in the operation of this equipment. DEATH ON CONTACT may result if personnel fail to observe safety precautions. Never work on electronic equipment unless there is another person nearby competent in administering first aid. When aided by operators, the technician must warn them about dangerous areas. Whenever possible, the power supply to the equipment must be shut off before beginning work on the equipment.
TM 11-5820-670-30 Adequate ventilation should be provided while using TRICHLOROTRIFLUOROETHANE. Prolonged breathing of vapor should be avoided. The solvent should not be used near heat or open flame; the products of decomposition are toxic and irritating. Since TRICHLOROTRIFLUOROETHANE dissolves natural oils, prolonged contact with skin should be avoided. When necessary, use gloves which the solvent cannot penetrate. If the solvent is taken internally, consult a physician immediately.
*TM 11-5820-670-30 HEADQUARTERS DEPARTMENT OF THE ARMY Technical Manual Washington, DC, 13 September 1985 No. 11-5820-670-30 AVIATION INTERMEDIATE MAINTENANCE MANUAL RADIO SET AN/ARC-131 (NSN 5821-00-937-4686) REPORTING ERRORS AND RECOMMENDING IMPROVEMENTS You can help improve this manual. If you find any mistakes or if you know of a way to improve the procedures, please let us know.
TM 11-5820-670-30 HOW TO USE THIS MANUAL This manual is designed to help you maintain Receiver-Transmitter, Radio RT-823/ARC-131 and Control, Radio Set C-7088/ARC-131 which are components of Radio Set AN/ARC-131. A front cover index is provided for quick reference to important information contained in this manual. Each item appearing on the front cover is boxed and identified by topic, with the page number where the information is located.
TM 11-5820-670-30 EL1AT231 Radio Set AN/ARC-131 (iii blank)/1-0
TM 11-5820-670-30 CHAPTER 1 INTRODUCTION Section Subject General Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Equipment Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Principles of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 1-2. MAINTENANCE FORMS, RECORDS, AND REPORTS. (CONT) DISCREPANCY IN SHIPMENT REPORT (DISREP) (SF 361) Fill out forward Discrepancy in Shipment Report (DISREP) (SF 361) as prescribed in AR 55-38/ NAVSUPINST 4610.33C/AFR 75-18/MCO P4610.19D/DLAR 4500.15. 1-3. REPORTING EQUIPMENT IMPROVEMENT RECOMMENDATIONS (EIR). If your Radio Set AN/ARC-131 needs improvement, let us know. Send us an EIR. You, the user, are the only one who can tell us what you don’t like about your equipment.
TM 11-5820-670-30 1-8. SAFETY, CARE, AND HANDLING. Observe all warnings, cautions and notes in this manual. This equipment can be extremely dangerous if these instructions are not followed. Ensure the following caution is observed as well. CAUTION Receiver-transmitter of radio set is compact and heavy. Use caution when handling it. Serious damage could result if mishandled and dropped. Section II EQUIPMENT DESCRIPTION Subject General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 1-11. DIFFERENCES BETWEEN MODELS/SILICON VERSIONS. (CONT) INTERCHANGEABILITY OF MODULES Germanium and silicon modules may be used together in the same radio with the following exceptions. Only germanium versions of the following modules should be used: First and Second IF. Amps A4100) IF.
TM 11-5820-670-30 Para Page 1-33 1-34 1-35 1-36 1-37 1-38 1-39 1-40 1-41 1-42 1-43 1-44 1-45 1-46 1-47 1-48 1-49 1-31 1-33 1-36 1-36 1-37 1-38 1-39 1-40 1-41 1-42 1-43 1-44 1-45 1-45 1-45 1-46 1-48 HOMING MODE Homing Signal Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-50 RF Control Assembly P/O Module A4500 (Homing Mode) . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51 IF.
TM 11-5820-670-30 1-12. GENERAL. This section contains information covering principles of operation of major electronic assemblies of the receiver-transmitter, beginning with the receiver. Material is presented in functional block diagram format, with supporting text which explains the operation of each electronic module in the radio. Details pertaining to operation of most individual components in each module are not discussed in this section.
TM 11-5820-670-30 1-13. RECEIVER SIGNAL FLOW. A system block diagram showing receiver signal flow can be found on FO-1 in the back of this manual. Refer to the foldout while reading the text in this paragraph. In the receive mode of operation, frequency modulated rf signals from the communications antenna are applied to reflectometer (1) and sidetone gate detector (2), in module A4500.
TM 11-5820-670-30 1-13. RECEIVER SIGNAL FLOW. (CONT) The 11.5 MHz if. output from the fifth if. amplifier is applied to limiter module A4200 (13). The limiter clips the positive and negative peaks of the input signal to ensure an output of constant amplitude. If the limiter output is not of constant amplitude, a distorted audio output occurs from the discriminator in module A4200 (14). The clipped if. modulated signal is applied to the discriminator from the limiter.
TM 11-5820-670-30 LOCAL OSCILLATOR AFC/CRYSTAL REFERENCE SYSTEM. (CONT) The heterodyning process in crs second mixer A3300 (6) produces sum and difference frequencies. Two of the difference frequencies are very close to 5.625 MHz. The frequency closest to 5.625 MHz is coupled across a 5.625 MHz tuned tank within the second mixer, to first and second if. amplifiers A3400 (8). Other frequencies are greatly attenuated by the resonant tank circuit. After amplification, the if.
TM 11-5820-670-30 1-15. CRS BALANACED MIXER A3200. The balanced mixer accepts inputs from the following two sources: EL1AT090 Local oscillator through high-pass filter FL3002 Harmonic generator Local oscillator signals are applied to the mixer through a buffer amplifier to prevent loading down the local oscillator. Twelve frequencies, 1 to 12 MHz, are applied to the mixer with the local oscillator’s output. The signals are heterodyned to produce four strong mixed output frequencies.
TM 11-5820-670-30 1-15. CRS BALANCED MIXER A3200. (CONT) Since the output of the balanced mixer is applied to a 53 MHz filter (FL3003), only two frequencies listed are close enough to the filter’s band pass to reach the next crs module without substantial attenuation. These two frequencies are 52.50 and 53.50 MHz, which are applied to the second mixer. 1-16. CRS SECOND MIXER A3300 AND CRYSTAL SWITCH A2000.
TM 11-5820-670-30 1-16. CRS SECOND MIXER A3300 AND CRYSTAL SWITCH A2000. (CONT) SECOND MIXER A3300 The second mixer performs a signal heterodyning function, mixing the output of the 53 MHz filter with a frequency from the interpolation oscillator. Within the mixer module is a tuned tank circuit which couples the mixer’s output to first and second if. amplifiers A3400. The tank circuit is tuned to resonate at 5.625 MHz so that frequencies near 5.
TM 11-5820-670-30 1-16. CRS SECOND MIXER A3300 AND CRYSTAL SWITCH A2000. (CONT) SECOND MIXER AND CRYSTAL SWITCH OPERATING EXAMPLE – Radio Frequency Selector Switches Set to 30.00 MHz EL1AT092 Two strong frequencies enter the second mixer from the 53 MHz filter, 53.50 and 52.50 MHz. These signals are heterodyned with the output from the interpolation oscillator. With the radio tuned to 30 MHz, crystal Y2006 is selected. This crystal sets the interpolation oscillator’s output at 46.850 MHz. When 46.
TM 11-5820-670-30 1-17. CRS FIRST AND SECOND IF. AMPLIFIER A3400/CRS THIRD IF. AMPLIFIER AND LIMITER A3500. EL1AT093 An intermediate frequency from the second mixer is applied to the first if. amplifier. The intermediate frequency is approximately 5.65 MHz for all front panel decimal control settings which are even, such as 30.00, 30.10, 30.20, etc. An if. of approximately 5.60 MHz is applied to the first if. amplifier for all odd decimal control settings, such as 30.05, 30.15, 30.25, etc. if.
TM 11-5820-670-30 1-17. CRS FIRST AND SECOND IF. AMPLIFIER A3400/CRS THIRD IF. AMPLIFIER AND LIMITER A3500. (CONT) The third if. amplifier increases the signal strength sufficiently to drive the limiter. The limiter clips the upper and lower peaks of the if. to maintain a constant amplitude required by the travis-type discriminator in hunt discriminator A3600. Filter FL3005 provides additional attenuation of all signals other than the if. input. 1-18.
TM 11-5820-670-30 1-18. CRS HUNT DISCRIMINATOR A3600, CRS PHASE DISCRIMINATOR A3700, AND REFERENCE OSCILLATOR A2000. (CONT) The hunt discriminator is tuned to a 5.625 MHz center frequency. It will therefore generate output signals when its if. input is substantially under or over 5.625 MHz, which condition corresponds to a large local oscillator error.
TM 11-5820-670-30 1-18. CRS HUNT DISCRIMINATOR A3600, CRS PHASE DISCRIMINATOR A3700, AND REFERENCE OSCILLATOR A2000. (CONT) HUNT DISCRIMINATOR, PHASE DISCRIMINATOR; REFERENCE OSCILLATOR – WORKING EXAMPLE – LOCAL OSCILLATOR AT CORRECT FREQUENCY EL1AT095 If the radio is set to 30.00 MHz, the local oscillator runs at 41.50 MHz, assuming that it is properly alined. In this case, the limiter output is 5.65 MHz. When 5.
TM 11-5820-670-30 1-18. CRS HUNT DISCRIMINATOR A3600, CRS PHASE DISCRIMINATOR A3700, AND REFERENCE OSCILLATOR A2000. (CONT) With the radio set to 30.00 MHz, the 5.65 MHz crystal is selected, causing the reference oscillator to output a 5.65 MHz fixed frequency. Since the reference oscillator and limiter output frequencies are the same, the phase discriminator does not output a dc voltage to the damping network. Therefore, no dc voltage will be present at TP3001 due to the phase discriminator action.
TM 11-5820-670-30 1-18. CRS HUNT DISCRIMINATOR A3600, CRS PHASE DISCRIMINATOR A3700, AND REFERENCE OSCILLATOR A2000. (CONT) The two signals entering the phase discriminator are 5.65 MHz from the reference oscillator and 5.70 MHz from limiter A3500. Because of the difference in frequencies, the phase discriminator outputs a dc voltage. This positive dc voltage is measurable at TP3001. 1-19. TIME DELAY CIRCUIT P/O MODULE A2100.
TM 11-5820-670-30 1-20. GEARBOX ASSEMBLY A9700. Refer to FO-3 in the back of this manual while reading the text in this paragraph. The electrical portion of gearbox assembly A9700 contains a standard Iedex stepping solenoid having 20 positions of 18 degrees rotation per step, a 24-position switch driven by a dc motor, and a dc motor to control band switching.
TM 11-5820-670-30 1-21. RF CONTROL ASSEMBLY P/O MODULE A4500 (RECEIVE MODE). EL1AT097 Frequency modulated rf from the communications antenna is applied through the primary of transformer T4501 to the sidetone gate detector. Very low levels of rf are coupled-to the secondary of transformer T4501 and then applied to the diode circuits. The diode circuits will not produce-an output unless the rf level is 0.6 watt or greater. In receive mode, the rf level entering the diode circuits is well below 0.
TM 11-5820-670-30 1-22. ANTENNA TUNING AND PROTECTION MODULE A1100. Frequency modulated rf signals from transmit/receive relay K4501 are fed through homer relay K4502 to the A1100 tuning circuits which consist of tuned tank circuits. The tuning circuits consist of an band, 30 MHz through 52.95 MHz, and a band, 53 MHz through 75.95 MHz. The gear train selects band or , depending on the setting of tuning dials at the control unit.
TM 11-5820-670-30 1-23. FIRST RF AMPLIFIER MODULE A1200. (CONT) The A1200 tuning circuits provide additional attenuation of unwanted frequencies by the action of their narrow band pass resonant tanks. 1-24. SECOND RF AMPLIFIER MODULE A1300. EL1AT100 Signals from the first rf amplifier are further amplified by the second rf amplifier which contains vacuum tube V1301. The tuning circuits function similarly to those in module A1200. 1-25. MIXER AND BUFFER AMPLIFIER A1400 (RECEIVE MODE).
TM 11-5820-670-30 1-15. MIXER AND BUFFER AMPLIFIER A1400 (RECEIVE MODE). (CONT) Mixer V1401 is the last of three vacuum tubes in the receiver section. During the receive operation it accepts the following inputs: Amplified frequency-modulated rf from module A1300 A frequency from the local oscillator which is, in the 11.5 MHz below the frequency of module A1300. band, 11.5 MHz above or in band The two signals applied to the mixer are heterodyned (mixed) to produce an if. which carries audio intelligence.
TM 11-5820-670-30 1-26. LOCAL OSCILLATOR MODULE A1500. (CONT) TUNING CIRCUITS The tuning circuits control the frequency of the oscillator. They contain resonant tank circuits with a mechanical linkage from a variable inductor to the gear train which enables the radio set to tune to the frequency set by the control unit automatically.
TM 11-5820-670-30 1-27. IF. ATTENUATOR MODULE A4900 (RECEIVE MODE). EL1AT103 In receive mode, if. attenuator module A4900 allows if. signals from the mixer to pass through the diode circuitry with minimum attenuation. Constant 16 vdc from homer relay K4502 is applied to a zener diode in the if. attenuator module. This causes the zener diode to apply an increased level of voltage to the diode circuitry, fully biasing the diodes.
TM 11-5820-670-30 1-29. THIRD, FOURTH, AND FIFTH IF. AMPLIFIER, LIMITER AND DISCRIMINATOR A4200. THIRD, FOURTH, AND FIFTH IF. AMPLIFIERS EL1AT105 The third, fourth, and fifth if. amplifiers provide additional gain necessary to drive the limiter. LIMITER AND DISCRIMINATOR The limiter receives if. from the fifth if. amplifier. The positive and negative peaks of the if. waveform are clipped by the limiter to provide a constant amplitude signal to the discriminator.
TM 11-5820-670-30 1-30. AUDIO AND SQUELCH PREAMPLIFIER MODULE A4300. The discriminator in module A4200 demodulates both the audio intelligence and the 150 Hz squelch tone signal. The 150 Hz squelch tone signal will be present in the receiver circuits only if the operator of a nearby transmitter is transmitting rf. Audio and squelch preamplifier A4300 subjects both these frequencies to preliminary stages of amplification, then applies the signal(s) to audio amp A5400. 1-31.
TM 11-5820-670-30 1-31. AUDIO AMPLIFIER MODULE A5400 (RECEIVE MODE). (CONT) The 150 Hz signal from output of amplifier Q5401 (1) operates relay K5501, which in turn, operates A2 and A1 of relay K5502, sending + 16 vdc to amplifier Q5403 (4). The 16 vdc from relay K5502 biases amplifiers Q5403 (4), Q5404 (5), and Q5405 (6), which will allow amplified audio intelligence to flow to transformer T5401 (7).
TM 11-5820-670-30 1-32. RECEIVER SQUELCH AMPLIFIER MODULE A5200 AND SQUELCH FILTER MODULE A5300 (RECEIVE MODE). (CONT) TONE (SQUELCH MODE) The received 150 Hz signal at the output of amplifier Q5401 (1) in the audio amplifier is applied through B3 and B2 of relay K5501 to amplifier Q5201 (11) in the squelch amplifier. The signal is amplified and applied to amplifiers Q5203 (12) and Q5204 (13) for further amplification.
TM 11-5820-670-30 1-32. RECEIVER SQUELCH AMPLIFIER MODULE A5200 AND SQUELCH FILTER MODULE A5300 (RECEIVE MODE). (CONT) DIS (SQUELCH MODE) When the squelch switch is set to DIS position, receiver squelch amplifier A5200 is bypassed since a squelch disable ground signal is applied through A3 and A2 of relay K5501 to relay K5502. A ground signal at K5502 causes + 16 vdc to flow through A1 and A2 to audio amplifier A5400 causing unsquelching.
TM 11-5820-670-30 1-33. TRANSMllTER SIGNAL FLOW. (CONT) Buffer amplifier A6400 also applies audio modulated signals to isolation amplifier A6600 (18) and then to mixer A1400 (19). The isolation amplifier assures that buffer amplifier (10) output signals are injected into the mixer, but local oscillator signals are not injected back into the buffer amplifier to cause spurious outputs.
TM 11-5820-670-30 1-34. MASTER OSCILLATOR FREQUENCY CONTROL LOOP. For proper radio transmitter operation, the fm output of the master oscillator must be within ± 3.5 kHz of the selected channel frequency. To prevent master oscillator frequency drift beyond these limits, a frequency control loop is built into the radio. The electronic modules that comprise the frequency control loop (automatic frequency control) are shown in FO-6. Correction of master oscillator frequency drift is accomplished in two ways.
TM 11-5820-670-30 1-34. MASTER OSCILLATOR FREQUENCY CONTROL LOOP. (CONT) Phase Discriminator The phase discriminator performs the following four functions: Phase comparison Correction voltage generation Demodulation Filtering Two rf signals are applied to phase discriminator (8) for comparison. One is the 11.5 MHz signal from first and second if. amplifiers (6). This frequency may not be exactly 11.5 MHz. The other input is an 11.5 MHz signal from 11.5 MHz modulator (7).
TM 11-5820-670-30 1-34. MASTER OSCILLATOR FREQUENCY CONTROL LOOP. (CONT) The hunt cutoff detector is basically a diode clipper and a filter, which clips off the negative half of the rf sine wave, filters it, and outputs a constant positive dc level. This dc level is applied to the hunt generator where it biases off the sawtooth generator. Consequently, no sawtooth voltage is applied to the master oscillator.
TM 11-5820-670-30 1-35. AUDIO MIXER MODULE A8600. EL1AT108 Audio signals from the interphone amplifier are applied through low-pass filter FL8701 whose main function is to attenuate signals above 3000 Hz. The 150 Hz signal generated in squelch amplifier A5200 is applied to the resistor network and combined with the filtered audio. The 150 Hz tone signal from squelch amplifier A5200 is always generated in transmit mode. The combined signals are applied to module A8100. 1-36. 11.
TM 11-5820-670-30 1-36. 11.5 MHz MODULATOR MODULE A8100. (CONT) The combined signal from the audio mixer is applied to the capacitance diodes which causes the frequency of oscillator Q8101 to deviate. Fm 11.5 MHz output from Q8101 is applied to buffer amps Q8102 and Q8103 for amplification, and then applied to phase discriminator A8200. The 11.5 MHz fm signal from buffer amplifier Q8103 is also applied to the crystal discriminator. The crystal discriminator compares 11.5 MHz fm with 11.
TM 11-5820-670-30 1-38. PHASE DISCRIMINATOR MODULE A8200. EL1AT111 Ring modulator in A8200 accepts two different signals. 11.5 MHz audio modulated signal from 11.5 MHz modulator A8100. 11.5 MHz unmodulated if. signal from mixer A1400 through A8300. Two 11.5 MHz signals are amplified by the drivers and applied to the ring modulator. The ring modulator produces both an audio output, determined by the modulation, and a dc voltage, determined by the difference between the two radio frequencies.
TM 11-5820-670-30 1-39. HUNT GENERATOR MODULE A8400. EL1AT112 The manner in which the hunt generator controls master oscillator frequency drift is discussed in paragraph 1-34. The following information covers operation of its subassemblies. When the master oscillator frequency shifts beyond the correcting range of the phase discriminator, the bias voltage from the hunt cutoff detector in module A4200 is removed, causing the sawtooth gate to stop conducting.
TM 11-5820-670-30 1-40. MASTER OSCILLATOR MODULE A6300. EL1AT113 The capacitance diodes in the A6300 module accept four signals. 1. 100 Hz sawtooth voltage from hunt generator A8400 2. ± dc correction voltage from the phase discriminator A8200 3. Voice signals riding on the ± dc correction voltage 4. 150 Hz tone signal generated in the squelch amplifier A5200 BUFFER CONTROL VOLTAGE The buffer control voltage consists of 100 Hz sawtooth voltage and ± dc correction voltage.
TM 11-5820-670-30 1-40. MASTER OSCILLATOR A6300. (CONT) CAPACITANCE DIODES The capacitance diodes are reverse-biased at 6.3 vdc. Any change in bias causes the effective capacitance of the diodes to change. The correcting voltages applied to the diodes alter the capacitance which changes the effective capacitance in the tuning circuits. This change in the tuning circuits changes the master oscillator operating frequency. The diodes also accept voice signals and 150 Hz tone signals.
TM 11-5820-670-30 1-41. BUFFER AMPLIFIER MODULE A6400 AND REGULATOR ASSEMBLY. (CONT) BUFFER AMPLIFIER The output of master oscillator A6300 is applied to isolation amplifier Q6401 which isolates the master oscillator to maintain frequency stability. Amplified signals from Q6401 are developed in the two secondary windings of transformer T6401. One secondary winding couples the signal to isolation amplifier module A6600 and the other winding applies the same signal to buffer amplifier Q6402 in module A6400.
TM 11-5820-670-30 1-43. MIXER AND BUFFER AMPLIFIER A1400 (TRANSMIT MODE). In transmit mode, mixer V1401 receives two signals: Frequency modulated signals from isolation amplifier A6600. The signal from local oscillator module A1500. The mixer heterodynes the two signals and applies a modulated 11.5 MHz if. signal to if. attenuator A4900 and first and second if. amplifier A8300 through buffer amp Q1401. Buffer amp Q1401 operates only in the transmit mode.
TM 11-5820-670-30 1-44. HUNT CUTOFF DETECTOR P/O MODULE A4200. EL1AT117 Frequency modulated 11.5 MHz if. from module A4100 enters the hunt cutoff detector from the fourth if. amp. The hunt cutoff detector rectifies the signal and applies a dc bias voltage to hunt generator A8400. 11.5 MHz if. is also coupled to the fifth if. amp and then proceeds through the receiver circuitry. The dc bias voltage is applied to the hunt generator only if 11.5 MHz if. is present at the fourth if. amp output.
TM 11-5820-670-30 1-45. AUDIO AMPLIFIER MODULE A5400 (TRANSMIT MODE). Refer to FO-4 while reading the text in this paragraph. Amplified audio signals from squelch preamplifier A4300 are applied to amplifier Q5401 (1) in the audio amplifier for amplification. In transmit mode, a transmit ground signal is applied to X2 of relay K5501, causing B2 and B1, and A2 and A1, to make contact. When B1 and B2 make contact, the amplified output of Q5401 is applied to low-pass audio filter FL5501 (2) only.
TM 11-5820-670-30 1-48. RF AMPLIFIER ASSEMBLY MODULE A6500. RF AMPLIFIERS EL1AT118 Frequency modulated signals from the master oscillator are applied through buffer amp A6400 to module A6500. Signals entering A6500 are applied to Q6501 and Q6502 for amplification. The tuning circuits, adjusted mechanically by the gear train, tune rf driver Q6502 for maximum gain which provides driving power for the final rf amp stages.
TM 11-5820-670-30 1-48. RF AMPLIFIER ASSEMBLY MODULE A6500. (CONT) The rf detector is a directional coupler circuit that samples the forward and reflected power components of the rf output signal. The voltages from the final rf amp stage are rectified by diodes CR6501 and CR6502 and applied to the agc amplifiers. AGC AMPLIFIERS EL1AT120 The rf and agc amplifiers form a feedback loop which ensure a constant level of rf output to module A4500.
TM 11-5820-670-30 1-49. RF CONTROL ASSEMBLY P/O MODULE A4500 (TRANSMIT MODE). Band-pass filter FL4501A filters out harmonics of all transmitted signals in the frequency range of 30.00 MHz to 52.95 MHz. Band-pass filter FL4501 B attenuates harmonics of all transmitted signals in the frequency range of 53.00 MHz – 75.95 MHz. The overall function of the filter is to attenuate all harmonics of the passband frequencies (30 MHz – 75.95 MHz) while offering minimum loss to the passband frequencies.
TM 11-5820-670-30 1-49. RF CONTROL ASSEMBLY P/O MODULE A4500 (TRANSMIT MODE). (CONT) When the push-to-talk button is pressed, transmit/receive relay K4501 is energized, allowing transmitted rf to flow to the sidetone gate detector and reflectometer from band-pass filter FL4501. Rf signals entering the detector are rectified by diode CR4514 and applied to amplifier Q4501. Amplifiers Q4501 and Q4502 will not conduct until 0.6 watt biases diode CR4514. When transmitted power reaches 0.
TM 11-5820-670-30 1-50. HOMING SIGNAL FLOW. Homing operation is available on any of 920 channels in the frequency range of 30.00 to 75.95 MHz. The homing circuit provides information to the aircraft homing indicator concerning the aircraft heading with respect to a transmitting station. To follow the homing circuits signal path, see FO-7 while reading the text in this paragraph. When the control unit mode selector switch is set to HOME, + 27.
TM 11-5820-670-30 1-50. HOMING SIGNAL FLOW. (CONT) The application of the dc signal to the vertical needle of the homing indicator provides the pilot with information to fly left or right. The if. signal in the if. agc amplifier (15) is applied to the homer signal strength amplifier (18) which supplies a dc signal to the homing indicator horizontal needle.
TM 11-5820-670-30 1-51. RF CONTROL ASSEMBLY P/O MODULE A4500 (HOMING MODE). DIODE SWITCH EL1AT125 Rf signals entering the left and right homing antennas are alternately switched through the diode switch to the rf attenuator circuit at a 100 Hz rate. The 100 Hz square wave from the 100 Hz oscillator is used to bias the diodes in the diode switch. When the square-wave bias voltage is positive(+), rf signals from the left homing antenna are coupled through the diode switch to the rf attenuator circuit.
TM 11-5820-670-30 1-51. RF CONTROL ASSEMBLY P/O MODULE A4500 (HOMING MODE). (CONT) The rf attenuator circuit operates only in homing mode and is controlled by agc voltage from the homer rf agc amplifier. When low level homing signals are applied from the diode switch to the rf attenuator, agc voltage from the agc amplifier increases, allowing signals to pass with no attenuation. As the homing signal level increases, agc voltage decreases causing the attenuator output level to decrease.
TM 11-5820-670-30 1-53. HOMER-DETECTOR AMPLIFIER ASSEMBLY A4800. 100 Hz OSCILLATOR EL1AT128 Transistors Q4801 and Q4802 form a common base square-wave oscillator having an output frequency of 100 Hz. Transformer T4801 couples the 100 Hz square wave to the synchronous detector and homer diode switch.
TM 11-5820-670-30 1-53. HOMER-DETECTOR AMPLIFIER ASSEMBLY A4800. (CONT) The homer if. signal from the hunt cutoff detector in the fourth if. amplifier is applied to rf agc amplifier Q4807. With weak received signals, conduction of transistor Q4807 is slight which causes Q4808 to conduct heavily and supply approximately 10 volts agc voltage to the rf attenuator (P/O module A4500). As the homer if. signal level increases, Q4807 starts to conduct harder and causes the conduction of Q4808 to decrease.
TM 11-5820-670-30 1-53. HOMER-DETECTOR AMPLIFIER ASSEMBLY A4600. (CONT) OFF COURSE SIGNAL AMPLIFIER EL1AT131 The homer if.-am signal, isolated by transistor Q4809, is applied to sensitivity amp Q4810. The bias level of Q4810 is established by if. agc voltage from the if. agc amp. When the received homing signal is of a low level, if. agc voltage causes transistor Q4810 to conduct harder allowing more of the homing signal to be applied to the synchronous detector.
TM 11-5820-670-30 1-53. HOMER-DETECTOR AMPLIFIER ASSEMBLY A4800. (CONT) The output if.-am signal from amplifier Q4810 is applied to transistors Q4803 and Q4804 which form the synchronous detector. The synchronous detector circuit is also driven by the 100 Hz oscillator used to alternately switch the homing signals from the left and right antennas into the circuit. When the positive and negative half cycles of the homer if.
TM 11-5820-670-30 1-54. RETRANSMIT OPERATION. NOTE This paragraph contains a discussion of retransmit operation. Not to duplicate other areas of the manual, the received and transmitted signals are not traced through the receiver-transmitter circuitry. Detailed interconnection of the radio sets and associated equipment operating in the retransmit mode is shown on FO-8. To follow the simplified interconnection of two radio sets operating in retransmit mode, see FO-9 while reading this paragraph.
TM 11-5820-670-30 1-54. RETRANSMIT OPERATION. (CONT) With K5502 energized, the retransmit control ground, which originates in the receiver-transmitter during the receive condition, is applied through contacts 5 and 6 of K5502 and then through the control units to transmitter key relay K9602 in radio set no. 2. Simultaneously, the received audio signal is coupled from radio set no. 1 through the control units to the transmitter circuits of radio set no. 2 for transmission.
TM 11-5820-670-30 1-56. VOLTAGE REGULATOR ASSEMBLY A2100. Voltage regulator assembly A2100 provides a regulated output of +16 vdc for circuits in the receivertransmitter. The regulator maintains + 16 vdc output over a wide range of current demands. Potentiometer R2106 adjusts biasing levels and the regulated output of +16 vdc, while +24 vdc biases voltage regulators Q2102 and Q2101. Voltage regulator assembly A2100 includes a time delay circuit which is discussed in paragraph 1-19. 1-57.
TM 11-5820-670-30 1-57. POWER SUPPLY ASSEMBLY A9500. (CONT) REGULATOR OPERATION The series regulators, connected in parallel, increase the current capabilities of the power supply and maintain +24 vdc at a constant level. If the required 24 vdc level increases above 24 volts, conduction of the voltage sensors decreases, causing conduction of the regulator driver to decrease.
TM 11-5820-670-30 1-58. RECEIVER-TRANSMITTER INTRAUNIT CIRCUIT FUNCTIONING. (CONT) In transmit operation, relay K9601 couples regulated +24 vdc through contacts 2 and 6 and contacts 1 and 5 to the rf control modules and rf amplifier. Application of +24 vdc to the rf control through connector P4501 pin 4, causes the communications antenna to be removed from the receiver input and connected to the output of band and band harmonic filters.
TM 11-5820-670-30 1-58. RECEIVER-TRANSMITTER INTRAUNIT CIRCUIT FUNCTIONING (CONT) METERING CIRCUIT See FO-12, receiver-transmitter, Radio RT-823/ARC-131, while reading this section. Test Switch S9601 on the receiver-transmitter front panel selects various operating voltages and outputs and applies them through series resistances when necessary to TEST METER M9601. The test meter displays these voltages to provide a quick check of radio set performance.
TM 11-5820-670-30 1-59. CONTROL, RADIO SET C-7088/ARC-131 FUNCTIONING. (CONT) When mode control switch S9105 is set to T/R position, + 27.5 vdc from the aircraft electrical system is applied to connector J9101 pins C, D, E, through the front and rear wafers of switch S9105D, and is distributed to the receiver-transmitter through connector J9101 pins e, f, and F. The front wafer of S9105C provides a path for the audio input in receive mode.
TM 11-5820-670-30 1-59. CONTROL, RADIO SET C-7088/ARC-131 FUNCTIONING. (CONT) Resistor R9102 serves as a dropping resistor to establish the proper signal level for the transmit audio input. The audio common in retransmit mode is connected through the front and rear wafers of switch S9105C to the aircraft interphone amplifier. In HOME position, the radio set provides an fm or cw homing facility which allows the pilot to home on a signal transmitted within a frequency range of 30.00 MHz to 75.95 MHz.
TM 11-5820-670-30 1-59. CONTROL, RADIO SET C-7088/ARC-131 FUNCTIONING. (CONT) When SQUELCH switch S9106 is set to TONE, the ground at contact 7 is connected through contact 8 to contact 9 on the rear wafer of S9105A. This ground is applied to pin X of connector J9101 only when the mode control switch is set to T/R or RETRAN position. From pin X, the squelch tone ground is connected through the interconnecting wiring and is used to operate the tone mode relays in the audiofrequency amplifier assembly.
TM 11-5820-670-30 1-59. CONTROL, RADIO SET C-7088/ARC-131 FUNCTIONING. (CONT) The homing indicator vertical (course) needle is controlled by the homer course voltage from the homer assembly. The homer course voltage is coupled from the receiver-transmitter to pin t of connector J9101. From pin t, the course voltage is connected through contacts 1 and 2 on the rear wafer of S9105B.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. Interunit functioning is presented to provide an understanding of the interrelations of several units in various operations of the radio set. Such an understanding will help maintenance personnel, when troubleshooting, to sectionalize to a defective module or unit.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) The + 27.5 vdc primary power is supplied to the radio set from the aircraft electrical system. Primary power is applied at pins C, D, and E of control unit electrical connector J9101. From pins C, D, and E, power is applied to contacts 1,2,3, and 5 of wafer D of mode control S9105. Control S9105 is shown in OFF position. In this position, no power is applied through the switch.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) In transmit operation, the control unit control switch is placed in T/R position as shown in FO-14. Input voltage, +27.5 vdc, is supplied by the aircraft electrical system and is applied to the radio set through connectors J9101 pin D, S9105 C, J9101 pin F, main connector P9801 pin 36, and connector P9501 pin 9 to the power supply. Application of +27.5 vdc activates the power supply.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) AUDIO CIRCUITS See FO-15 while reading this section. Audio signals from the microphone are coupled through the interphone amplifier to pins y (high) and kk (low) of control unit connector J9101. The 110 ohm and 43 ohm resistors form an impedance matching pad. The audio signal is then coupled through mode control switch S9105.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) In T/R mode, primary + 27.5 vdc power is applied from pins C, D, and E of control unit connector J9101 to contacts 1,2,3, and 5 of S9105D front. Primary power is connected through the switch to contacts 9, 10, 11, and 12 to pins F, e, and f of control unit connector J9101.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) Retransmit Mode (RETRAN) In RETRAN mode, + 27.5 vdc primary power is applied through S9105D front to the receivertransmitter as indicated in the T/R position except that contact 3 is used instead of contact 5. Received audio signals are coupled from the receiver-transmitter into control unit connector J9101 at pins JJ (high) and B (low).
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) Homing Mode (HOME) In homing mode, +27.5 vdc primary power is applied as indicated in T/R mode, except that + 27.5 vdc is also supplied to the rf control to operate the homing circuits. The homer operate voltage is coupled from contacts 9, 10, 11, and 12 of S9105D front to contact 8 of S9105A front. In HOME mode, contact 8 is connected to contact 7.
TM 11-5820-670-30 1-60. RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) SQUELCH CONTROL CIRCUITS See FO-17 while reading this section. Squelch Disable Mode (DIS) When SQUELCH control S9106 is set to DIS, the ground at contact 7 is connected through S9106 from contact 5 and then to pin V of control unit connector J9101. The ground is then connected through interconnecting wiring to pin 12 of receiver-transmitter connector P9601.
TM 11-5820-670-30 RADIO SET AN/ARC-131 INTERUNIT CIRCUIT DETAILS. (CONT) SQ ADJ potentiometer R9602 allows front panel adjustment of the carrier squelch signal. Normal setting of the SQ ADJ potentiometer is at a point just above the level where noise breaks squelch. The squelch circuits can be disabled by pressing the SQ DIS switch S9602 on the receiver-transmitter. This has the same effect as switching the SQUELCH control on the control unit to DIS position.
TM 11-5820-670-30 1-61. TUNING SYSTEM RADIO SET AN/ARC-131. Receiver-Transmitter Radio RT-823/ARC-131 operates on any of 920 channels within range from 30 to 75.95 MHz, in 0.05 MHz increments. The operating frequency is selected at Control, Radio Set C-7088/ARC-131 and the actual tuning takes place in receiver-transmitter, Radio RT-823/ARC-131 and the antenna coupler. The control unit provides whole and decimal MHz control information to the gearbox in the receiver-transmitter.
TM 11-5820-670-30 1-61. TUNING SYSTEM RADIO SET AN/ARC-131. (CONT) Correct ground combinations are applied to pins j, K, M, Z, and AA of control unit connector J9101. The selection code for determining proper band selection in the antenna coupler is developed by the front wafer of S9101D. The band selection code is connected through pins g and H of connector J9101.
TM 11-5820-670-30 1-61. TUNING SYSTEM RADIO SET AN/ARC-131. (CONT) These lines are grounded in various combinations at the control unit to provide required tuning for the particular frequency. When the manual frequency selector switches are positioned to 30.00 MHz, as shown in FO-19, grounds are applied to tuning control lines MHz select A, MHz select E, 0.05 MHz select A, 0.05 MHz select E, and band lines for the receiver-transmitter and antenna coupler.
TM 11-5820-670-30 1-61. TUNING SYSTEM RADIO SET AN/ARC-131. (CONT) Conduction of Q9702 simultaneously applies a ground signal to the control coil of K9701 and through diode CR9711. Contacts 4 and 6 of relay K9701 connects + 27.5 vdc to motor 69702 when K9701 energizes. Motor 69702 momentarily operates switch S9704 causing relay K9701 to momentarily energize and reenergize. This action causes +27.5 vdc to be applied and removed from motor 69702 in synchronism with switch S9704.
TM 11-5820-670-30 1-61. TUNING SYSTEM RADIO SET AN/ARC-131. (CONT) The geneva assembly also drives open-seeking switch S9705 through a 6 to 1 speed-reducing gear train. Each time the slotted wheel on the geneva assembly is engaged and rotated 90 degrees, switch S9705 is rotated through 15 degrees which corresponds to a 1 MHz change in frequency. Operation of the differential is based on the principle that both 1 and 0.05 MHz tuning inputs produce an output, but neither input affects the other.
TM 11-5820-670-30 1-61. TUNING SYSTEM RADIO SET AN/ARC-131. (CONT) RF OSCILLATOR ASSEMBLY MECHANICAL TUNING The shaft of the 0.05 MHz cam is mechanically coupled to the rotor of crystal selector switch S2001. The camshaft rotates the switch through 360 degrees in 20 18-degree steps. At each switch position, the rotor of switch S2001A connects 1 of 10 crystals into the collector circuit of interpolation oscillator Q2001 within the rf oscillator assembly.
TM 11-5820-670-30 CHAPTER 2 MAINTENANCE Subject Section Page I II Ill IV V 2-1 2-2 2-50 2-126 2-150 Repair Parts, Special Tools, and TMDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Performance Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 Section II PERFORMANCE TESTS Subject Para Page General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3 2-3 VOLTAGE DISTRIBUTION Test Meter Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 2-3. GENERAL. This section contains performance test procedures for use with Maintenance Kit MK-1035/ARC-131 and discrete test equipment (TMDE). They will enable you to determine whether or not an rt is operating acceptably. Each test procedure checks specific functions of the receiver-transmitter to help you find and isolate faults. Each test is complete and maybe performed individually.
TM 11-5820-670-30 2-4. TEST METER TESTS. PURPOSE The test meter tests provide an overall performance check of the radio set. Test switch S9801 selects various operating voltages in the receiver-transmitter and applies them to test meter M9601. TEST EQUIPMENT AND MATERIALS Power Supply PP-2953/U Maintenance Kit MK-1035/ARC-131 All cables ore part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-4. TEST METER TESTS. (CONT) EQUIPMENT CONTROL OR SWITCH POSITION/SETTING TS-25751ARC-131 FREQ sel SQUELCH MODE SWITCH TRANSMIT SWITCH WIDEBAND-NAR BAND ON-AGC HI-LO +28 VDC 30 MHz DIS TIR ON NAR BAND ON HI ON TEST PROCEDURE 1. On the RT-823/ARC-131, successively set TEST SWITCH for each position (1 through 6) and observe indication on TEST METER. See the following table.
TM 11-5820-670-30 2-5. AUDIO POWER OUTPUT AND DISTORTION TEST. PURPOSE This test checks the receiver section of the radio set. Two signal generators simulate a frequency modulated signal. The rt demodulates the signal and outputs audio power containing a percentage of distortion, which is measured by a spectrum analyzer.
TM 11-5820-670-30 2-5. AUDIO POWER OUTPUT AND DISTORTION TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING TS-25751ARC-131 MODE SWITCH VOL SQUELCH FREQ sel T/R Maximum (clockwise) DIS 60.05 MHz AN/URM-127 Freq dial FREQ RANGE MULTIPLIER OUTPUT CONTROL 10 X 100 As required in test procedures.
TM 11-5820-670-30 2-5. AUDIO POWER OUTPUT AND DISTORTION TEST. (CONT) 4. Tune signal generator AN/URM-103 to 60.05 MHz as indicated by maximum indication on TS-723/U meter. STANDARD. 2.17 to 3.45 vrms (5 mw ± 2 db) 5. If TS-723A/U meter does not indicate between specified limits, see troubleshooting chart 2-6. 6. Disconnect jumper between AF INPUT and METER terminals on TS-723A/U. Read audio distortion in percentage. NOTE Tune the AN/URM-103 slightly for minimum distortion as indicated on the TS-723A/U.
TM 11-5820-670-30 2-6. AUDIOFREQUENCY RESPONSE AND FRONT PANEL METER TEST. (CONT) EL1AT141 INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SEITING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel T/R Maximum (clockwise) DIS 60.05 MHz AN/URM-103 BAND SWITCH and RF TUNING CONTROL FUNCTION switch RF OUTPUT switch Adjust to 60.05 MHz.
TM 11-5820-670-30 2-6. AUDIOFREQUENCY RESPONSE AND FRONT PANEL METER TEST. (CONT) CONTROL AND SWITCH SETTINGS (CONT) EQUIPMENT CONTROL OR SWITCH LO-HI RF SET to LINE CONTROL and LO RF UV DEVIATION RANGE KHZ switch DEVIATION control AN/URM-127 TS-723A/U Freq dial FREQ RANGE MULTIPLIER OUTPUT CONTROL POSITION/SETTING Adjust for 10 microvolt. 10 Midrange position 10 X 1K Adjust as indicated in test procedure. Adjust as indicated in test procedure. TEST PROCEDURE 1. 2. 3. 4.
TM 11-5820-670-30 2-6. AUDIOFREQUENCY RESPONSE AND FRONT PANEL METER TEST. (CONT) 10. Observe audio output change in db from the 1000 Hz reference (step 2). STANDARD. + 2 db -3 db 11. If audio output change is not within + 2 db to -3 db, see troubleshooting chart 2-8. 12. Disconnect cable CG-3371/U (W7) from WIDEBAND J108 and reconnect to NORMAL J107 on test set. 13. Repeat steps 1 and 2. 14. Rotate TEST switch on front panel of RT-823/ARC-131 and verify the following TEST METER indications.
TM 11-5820-670-30 2-7. RECEIVER SENSITIVITY, QUIETING, AND LIMITING TEST. (CONT) TEST SETUP Connect equipment as shown in test setup diagram. Turn on all test equipment and allow at least 5 minutes for warmup. EL1AT141 INITIAL EQUIPMENT CONTROL SETTINGS. Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT TS-2575/ARC-131 2-12 CONTROL OR SWITCH POSITION/SETTING MODE SWITCH VOL SQUELCH FREQ sel T/R Maximum (clockwise) DIS 30.
TM 11-5820-670-30 2-7. RECEIVER SENSITIVITY, QUIETING, AND LIMITING TEST. (CONT) CONTROL OR SWITCH POSlTION/SETTING BAND SWITCH and RF TUNING CONTROL Adjust as required in test procedures. EXT MOD LO 0-10 KUV EQUIPMENT AN/URM-103 FUNCTION switch RF OUTPUT switch LO-HI RF SET to LINE control and LO RF UV DEVIATION RANGE KHZ switch DEVIATION control Adjust for 10 microvolt.
TM 11-5820-670-30 2-8. MAXIMUM SIGNAL PLUS NOISE-TO-NOISE RATlO TEST. PURPOSE This test checks the ratio of received audio signal power and noise power when rt is in receive mode. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Signal Generator AN/URM-127 Spectrum Analyzer TS-723A/U Fuseholder MX-1730/U Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram.
TM 11-5820-670-30 2-8. MAXIMUM SIGNAL PLUS NOISE-TO-NOISE RATlO TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTlNGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ set T/R Maximum (clockwise) DIS 30.
TM 11-5820-670-30 2-9. RECEIVER CARRIER SQUELCH SENSITIVITY TEST. PURPOSE This test checks the squelch capability when carrier squelch is selected on the control unit. Squelching and unsquelching in the CARR mode occur at specified voltage levels. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Signal Generator AN/URM-127 Spectrum Analyzer TS-723A/U Power Supply PP-2953/U All cables are part of MK-1035/ARC Connect equipment as shown in test setup diagram.
TM 11-5820-670-30 2.9. RECEIVER CARRIER SQUELCH SENSITIVITY TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTlNGS CONTROL OR SWITCH EQUIPMENT POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel T/R Maximum (clockwise) CARR 30.
TM 11-5820-670-30 2-9. RECEIVER CARRIER SQUELCH SENSITIVITY TEST. (CONT) STANDARD. Audio is present. 7. If audio is not present, see troubleshooting chart 2-11. 8. Observe AN/URM-103 output level (squelch pull-in). STANDARD. 0.7 microvolt maximum 9. If AN/URM-103 output level is more than 0.7 microvolt, see troubleshooting chart 2-11. 10. Reduce AN/URM-103 output level until audio output indication disappears. Observe AN/URM103 output level (squelch dropout). STANDARD. 0.55 microvolt maximum 11.
TM 11-5820-670-30 2-10. RECEIVER TONE SQUELCH SENSITIVITY TEST. PURPOSE This test checks the squelch capability when tone squelch is selected on the control unit. Squelching and unsquelching in the TONE mode occur at various voltage levels.
TM 11-5820-670-30 2-10. RECEIVER TONE SQUELCH SENSITIVITY TEST. (CONT) TEST SETUP Connect equipment as shown in test setup diagram. Turn on both AN/URM-127 units and set their amplitude controls for a zero output. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT146 INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table.
TM 11-5820-670-30 2-10. RECEIVER TONE SQUELCH SENSITIVITY TEST. (CONT) CONTROL AND SWITCH SETTINGS CONTROL OR SWITCH EQUIPMENT POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ set T/R Maximum (clockwise) CARR 30.00 MHz TS-723A/U FUNCTION switch RANGE AF-RF switch DISTORTION X 10 AF AN/URM-103 BAND SWITCH and RF TUNING CONTROL FUNCTION switch RF OUTPUT switch LO-HI RF SET to LINE CONTROL and LO RF UV Adjust to 30.00 MHz.
TM 11-5820-670-30 2-10. RECEIVER TONE SQUELCH SENSITIVITY TEST. (CONT) 12. Reduce AN/URM-103 output level until audio output indication disappears, and observe AN/URM-103 output level (squelch dropout). STANDARD. 0.4 microvolt 13. If AN/URM-103 output level does not indicate 0.4 microvolt, see troubleshooting chart 2-12. 14. Repeat steps 1 through 14, adjusting the TS-2575/ARC-131 for each of the following frequencies: 41.00 MHz, 52.00 MHz, 53.00 MHz, 65.00 MHz, and 75.00 MHz. 2-11.
TM 11-5820-670-30 2-11. TRANSMITTER POWER OUTPUT TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS CONTROL OR SWITCH EQUIPMENT POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel HI-LO switch TRANSMIT switch T/R Maximum (clockwise) DIS 30.
TM 11-5820-670-30 2-12. TRANSMITTER TONE MODULATION TEST. PURPOSE This test checks the frequency and deviation of the 150 Hz tone signal generated in the rt when the mode switch is set at T/R. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Electronic Counter Digital Readout AN/USM-207 Modulation Meter ME-57/U Power Supply PP-2953/U All cables are port of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-12. TRANSMITTER TONE MODULATION TEST. (CONT) CONTROL AND SWITCH SETTlNGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel TRANSMIT switch T/R Maximum (clockwise) DIS 75.95 MHz OFF ME-57/U TUNING DEVIATION RANGE – KC FREQUENCY RANGE – MC Selector switch 75.95 MHz 20 55-120 TUNE C-1611 D/AlC Transmit-lnterphone selector RECEIVER 1 switch 1 ON TEST PROCEDURE 1.
TM 11-5820-670-30 2-13. TRANSMlllER DEVIATION NARROW BAND TEST. PURPOSE This test checks the transmitter deviation when the rt is transmitting rf signals. Deviation occurs as a result of transmitting harmonic and beat frequencies. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-127 Electronic Voltmeter ME-30(E)/U Modulation Meter ME-57/U Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram.
TM 11-5820-670-30 2-13. TRANSMITTER DEVIATION NARROW BAND TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel TRANSMIT switch HI-LO switch T/R Maximum (clockwise) DIS 30.00 MHz OFF LO AN/URM-127 Freq dial FREQ RANGE MULTIPLIER OUTPUT CONTROL 10 X 100 As specified in procedure.
TM 11-5820-670-30 2-14. TRANSMITTER DISTORTION NARROW BAND TEST. PURPOSE Distortion will ruin the quality of an audio signal and must, therefore, be kept at the lowest possible level. This test measures the percentage of distortion in the signal transmitted by the rt.
TM 11-5820-670-30 2-14. TRANSMllTER DISTORTION NARROW BAND TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTlNGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS CONTROL OR SWITCH EQUIPMENT POSITION/SETTING TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel TRANSMIT switch HI-LO switch T/R Maximum (clockwise) DIS 30.00 MHz OFF LO AN/URM-127 Freq dial FREQ RANGE MULTIPLIER OUTPUT CONTROL 10 X 100 As specified in test procedure.
TM 11-5820-670-30 2-15. TRANSMITTER SIGNAL PLUS NOISE-TO-NOISE RATIO TEST. PURPOSE This test checks the transmitted power to noise ratio. Transmitted noise must be 35 db below transmitted power. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Modulation Meter ME-57/U Spectrum Analyzer TS-723A/U Signal Generator AN/URM-127 Electronic Voltmeter ME-30(E)/U Power Supply PP-2953/U All cobles are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram.
TM 11-5820-670-30 2-15. TRANSMITTER SIGNAL PLUS NOISE-TO-NOISE RATlO TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING RT-823/ARC-131 XMTR HI-LO LO TS-2575/ARC-131 MODE SWITCH VOL SQUELCH FREQ sel HI-LO switch TRANSMIT switch T/R Maximum (clockwise) DIS 30.00 MHz LO OFF AN/URM-127 Freq dial FREQ RANGE MULTIPLIER OUTPUT CONTROL 10 X 1000 As specified in procedure.
TM 11-5820-670-30 2-16. TRANSMITTER FREQUENCY STABILITY TEST. PURPOSE This test checks the frequency of the transmitter power at several points on the rt’s bandwidth. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Electronic Counter Digital Readout AN/USM-207 Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-16. TRANSMITTER FREQUENCY STABILITY TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTlNG RT-823/ARC-131 XMTR HI-LO LO TS-2575/ARC-131 MODE SWITCH SQUELCH FREQ sel TRANSMIT switch HI-LO switch T/R CARR 75.
TM 11-5820-670-30 2-17. TRANSMlTTER AUTOMATIC FREQUENCY SELECTION AND CHANNEL CHANGING TONE TEST. PURPOSE This test checks the rt’s ability to tune to a selected frequency automatically in a specified period of time. This test also checks the 800 Hz tone generated when the rt is transmitting. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Power Supply PP-2953/U Stopwatch All cables are part of MK-1035/ARC Connect equipment as shown in test setup diagram.
TM 11-5820-670-30 2-17. TRANSMITTER AUTOMATIC FREQUENCY SELECTION AND CHANNEL CHANGING TONE TEST. (CONT) TEST PROCEDURE 1. Set frequency selectors to 30.00 MHz and allow radio set to tune; then set MODE SWITCH to OFF. 2. Change frequency selectors to 75.00 MHz and set MODE SWITCH to T/R. 3. Using a stopwatch, measure time required for tuning. STANDARD. 7 seconds maximum 4. If radio set takes longer than 7 seconds to tune, see troubleshooting chart 2-20. 5.
TM 11-5820-670-30 2-18. TRANSMlTTER SIDETONE TEST. (CONT) TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT153 INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table.
TM 11-5820-670-30 2-18. TRANSMITTER SIDETONE TEST. (CONT) CONTROL AND SWITCH SETTINGS EQUIPMENT POSITION/SETTING CONTROL OR SWITCH TS-2575/ARC-131 MODE SWITCH SQUELCH VOL FREQ sel T/R DIS Maximum (clockwise) 31.00 MHz C-1611 D/AIC Transmit-lnterphone selector 1 AN/URM-127 Freq dial FREQ RANGE MULTIPLIER OUTPUT CONTROL 100 X 10 As specified in procedure.
TM 11-5820-670-30 2-19. HOMING SENSITIVITY TEST. PURPOSE This test checks homing signals that operate vertical and horizontal needles of homing indicator. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Fuseholder MX-1730/U Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-19. HOMING SENSITIVITY TEST. (CONT) CONTROL AND SWITCH SETTINGS POSITION/SETTING EQUIPMENT CONTROL OR SWITCH TS-2575/ARC-131 MODE SWITCH SQUELCH FREQ sel LEFT and RIGHT HOMER ATTEN HOME CARR 31.00 MHz 0 AN/URM-103 BAND SWITCH and RF TUNING control FUNCTION switch RF OUTPUT switch LO-HI RF SET to LINE control and LO RF UV Adjust to 31.00 MHz. MOD OFF LO 0-10 KUV Adjust as required in procedure. TEST PROCEDURE 1.
TM 11-5820-670-30 2-19. HOMING SENSITIVITY TEST. (CONT) TEST PROCEDURE (CONT) 12. Adjust AN/URM-103 for zero input to the radio set. STANDARD. Horizontal needle should be near bottom of homing indicator lD-48/ARN. 13. If horizontal needle is not near bottom of indicator, see troubleshooting chart 2-23. 14. Set test set FREQ sel for 31.00 MHz and LEFT and RIGHT HOMER ATTEN controls to 0. 15. Set AN/URM-103 DEVIATION RANGE KHZ switch to 10 and adjust DEVIATION control for 8 kHz deviation. 16.
TM 11-5820-670-30 2-20. C-7088/ARC-131 MODE SWITCH SELECTION AND FRONT PANEL ILLUMINATION TEST. (CONT) TEST SETUP Connect equipment as shown in test setup diagram. Remove receiver-transmitter case (para 2-39). Replace control unit in test set with control unit under test. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT155 INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table.
TM 11-5820-670-30 2-20. C-7088/ARC-131 MODE SWITCH SELECTION AND FRONT PANEL ILLUMINATION TEST. (CONT) TEST PROCEDURE Set C-7088/ARC-131 MODE SWITCH to OFF and SQUELCH switch to DIS. Set frequency selectors on C-7088/ARC-131 for 30.95 MHz. Swing open amplifier modulator assembly on receiver-transmitter to permit viewing of MHz indicator on gearbox assembly. Swing open if. amplifier assembly on receiver-transmitter to permit viewing kHz indicator on gearbox assembly.
TM 11-5820-670-30 2-21. SQUELCH SWITCH AND FREQUENCY SELECTION TEST. PURPOSE This test checks for proper operation of the control unit’s squelch functions. The test also includes a check of the calibration between the control unit frequency selectors and gearbox assembly indicators.
TM 11-5820-670-30 2-21. SQUELCH SWITCH AND FREQUENCY SELECTION TEST. (CONT) TEST PROCEDURE 1. Set control unit SQUELCH switch under test to CARR. 2. Rotate receiver-transmitter SQ ADJ control fully counterclockwise. STANDARD. Presence of noise in speaker. 3. If no noise is present, see troubleshooting chart 2-24, item 5. 4. Rotate SQ ADJ fully clockwise. STANDARD. Absence of noise in speaker. 5. If noise is present in speaker, see troubleshooting chart 2-24, item 5. 6.
TM 11-5820-670-30 2-21. SQUELCH SWITCH AND FREQUENCY SELECTION TEST. (CONT) 14. If kHz indicator on gearbox assembly does not correspond to last two digits of selected frequency, see troubleshooting chart 2-24, item 7. 15. Increase frequency setting of control unit from 30.00 MHz to 52.00 MHz in 1 MHz steps. STANDARD. The MHz indicator on gearbox assembly should correspond to frequency selected at control unit. Antenna coupler simulator should also indicate the tens and units digits selected. 16.
TM 11-5820-670-30 2-22. RETRANSMIT RECEIVE TEST. PURPOSE This test checks the rt and control unit when the radio set is receiving rf in the retransmit mode. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Receiver-Transmitter, Radio RT-823/ARC-131 Headset/Microphone H-78/AIC Electronic Voltmeter ME-30E/U All cables are part of MK-1035/ARC TEST SETUP Fuseholder MX-1730/U Power Supply PP-2953/U Connect equipment as shown in test setup diagram.
TM 11-5820-670-30 2-22. RETRANSMIT RECEIVE TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS CONTROL OR SWITCH EQUIPMENT POSITION/SETTING TS-2575/ARC-131 +28 VDC ON-OFF WIDEBAND-NAR BAND TRANSMIT switch ON NAR BAND OFF C-1611 D/AIC VOL Midrange position ME-30E/U Selector switch RANGE AC 3V C-7088/ARC-131 MODE SWITCH FREQ sel SQUELCH VOL RETRAN 40.
TM 11-5820-670-30 2-23. RETRANSMIT TRANSMIT TEST. PURPOSE This test checks the rt and control unit when the radio set is transmitting rf in the retransmit mode. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Modulation Meter ME-57/U Electronic Voltmeter ME-30E/U Signal Generator AN/URM-127 Headset/Microphone H-78/AIC All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-23. RETRANSMIT TRANSMIT TEST. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS POSITION/SETTING EQUIPMENT CONTROL OR SWITCH TS-2575/ARC-131 +28 VDC ON-OFF WIDEBAND-NAR BAND TRANSMIT switch HI-LO switch ON NAR BAND OFF LO C-1611 D/AIC VOL Midrange position ME-30E/U Selector switch RANGE AC 3V ME-57/U TUNING DEVIATION RANGE - KC FREQUENCY RANGE – MC Selector switch 60.
TM 11-5820-670-30 Section Ill TROUBLESHOOTING Subject Para Page General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24 How to Use the Troubleshooting Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-25 Troubleshooting Charts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 2-24. GENERAL. (CONT) OVERALL TROUBLESHOOTING APPROACH When a radio set fails to meet a designated standard during a performance test, a reference is made in the test procedure to a specific troubleshooting chart which can then be used to locate the cause of the nonperformance.
TM 11-5820-670-30 2-24. GENERAL. (CONT) Troubleshooting procedures in this section make use of TMDE and Maintenance Kit, Electronic Equipment MK-1035/ARC-131. Specific test arrangements are given for each procedure. A preliminary status condition for the maintenance kit is set up and then changed as required to perform troubleshooting procedures. Complete descriptive data and instructions for operating the maintenance kit are given in TM 11-66251610-12.
TM 11-5820-670-30 2-25. HOW TO USE THE TROUBLESHOOTING CHARTS. NOTE 1. The following measurement checks distortion at 1020 Hz. The preceding illustration is an example of a logic flow chart. Refer to the illustration while reading the following information. START Each chart has a start segment, indicating the start of the troubleshooting procedure. TEST PROCEDURE INSTRUCTIONS Test procedure instructions appear in a rectangular box. These instructions usually contain specific test points to be probed.
TM 11-5820-670-30 2-25. HOW TO USE THE TROUBLESHOOTING CHARTS. (CONT) CORRECTIVE ACTION OR ADDITIONAL INSTRUCTION A corrective action box or additional instruction box always follows a decision diamond. If a radio set response does not meet the standard set in the decision diamond, the appropriately marked flow line from the decision diamond will usually be followed to a corrective action box.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) PRELIMINARY PROCEDURE. Set up equipment as shown in diagram. NOTE: INDICATES EQUIPMENT MARKING EL1AT159 NOTE Red covered battery clip on test set power cable connects to + 27.5 vdc power supply outlet. Black covered battery clip connects to ground. 1. Adjust power supply for an output of + 27.5 vdc. 2. Set test set controls as indicated in the following table.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-1 Voltage Distribution Troubleshooting (Sheet 1 of 5) NOTES 1. See FO-11 for primary power distribution. 2. If open circuits are found, refer rt to a higher level of maintenance. CHECK DISTRIBUTION OF +24 VDC TO RT ASSEMBLIES FOR POSSIBLE OPEN CIRCUITS. SEE CHART 2-3. CHECK FOR POSSIBLE SHORT CIRCUIT. PERFORM TROUBLESHOOTING CHART . . 2-2. PERFORM RT TEST METER TEST (PARA 2-4). PERFORM TROUBLESHOOTING CHART 2-3.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-1 Voltage Distribution Troubleshooting (Sheet 2 of 5) PERFORMTROUBLESHOOTING CHART 2-4. MEASURE VDC TO GROUND AT TP9501 ON A9500 ASSEMBLY. SEE ILLUSTRATION, SH 5. MEASURE BDC TO GROUND AT P9502 ON A9500 ASSEMBLY. SEE ILLUSTRATION, SH 5. PER FORM RT TEST METER TEST (PARA 2-4). PERFORM RT TEST METER TEST (PARA 2-4).
TM 11-5820-670-30 2-26 TROUBLESHOOTING CHARTS. (CONT) CHART 2-1 Voltage Distribution Troubleshooting (Sheet 3 of 5) NOTES 3. R9511 is located on underside of circuit card on A9500. MEASURE VDC TO GROUND AT TP9504 ON A9500 ASSEMBLY. SEE ILLUSTRATION, SH 5. EL1AT175 CAUTION Be careful not to short out the cord to nearby components while power is applied to A9500. PERFORM RT TEST METER TEST (PARA 2-4). REPLACE A9500 ASSEMBLY (PARA 2-42). PERFORM RT TEST METER TEST (PARA 2-4).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-1 Voltage Distribution Troubleshooting (Sheet 4 of 5) NOTES 4. A2100 Terminal board. CHECK DISTRIBUTION OF +16 VDC. SEE CHART 2-4. Connect positive (+) lead of meter to pin 6 and negative (–) lead to pin 9. PERFORM RT TEST METER TEST (PARA 2-4). REPLACE VOLTAGE REGULATOR ASSEMBLY A2100 (PARA 2-50). PER FORM RT TEST METER TEST (PARA 2-4).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-2 + 27.5 vdc Circuit Troubleshooting (Sheet 1 of 3) NOTES 1. P9501 pin locations. EL1AT161 REPLACE POWER SUPPLY ASSEMBLY A9500 (PARA 2-42). UNPLUG P5501 FROM J5501. SEE ILLUSTRATION, SH 2. 1 CH 2-1 UNPLUG P4501 FROM J4501 SEE ILLUSTRATION, SH 2. REPLACE A4500 ASSEMBLY (PARA 2-49). REPLACE A5500 ASSEMBLY (PARA 2-44).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-2 +27.5 vdc Circuit Troubleshooting (Sheet 2 of 3) NOTES 2. Remove relays and replace in this order: K9601, K9602, K9603, K9604, and K9606. See sh 3 for relay locations. 3. See FO-11 for primary power distribution circuits. REPLACE A9700 ASSEMBLY (PARA 2-71). ALINE (PARA 2-29).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-2 +27.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-3 +24 vdc Regulated Circuit Troubleshooting (Sheet 1 of 4) NOTES 1. P9501 pin locations. EL1AT161 REPLACE POWER SUPPLY ASSEMBLY A9500. (PARA 2-42). 2-64 2. Remove relay and replace in this order: K9601 and K9605. See sh 4 for relay location. 3. See FO-11 for primary power distribution circuits.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-3 +24 vdc Regulated Circuit Troubleshooting (Sheet 2 of 4) EL1AT164 REPLACE POWER SUPPLY ASSEMBLY A9500. (PARA 2-42). 3 CH 2-1 REPLACE A5500 ASSEMBLY (PARA 2-44). REPLACE A2100 ASSEMBLY (PARA 2-50).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-3 +24 vdc Regulated Circuit Troubleshooting (Sheet 3 of 4) REPLACE A9700 ASSEMBLY PARA 2-71). ALINE (PARA 2-29). 3 CH 2-1 REPLACE A1000 ASSEMBLY (PARA 2-68). ALINE (PARA 2-35).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-4 + 16 vdc Circuit Troubleshooting (Sheet 1 of 4) NOTES 1. A2100 terminal board. REPLACE A2100 ASSEMBLY (PARA 2-50). EL1AT167 DISCONNECT P4902 FROM J4902 ON ASSEMBLY A4900. SEE ILLUSTRATION, SH 4. 4 CH 2-1 DISCONNECT P3001 FROM ASSEMBLY A3000. SEE ILLUSTRATION, SH 4. REPLACE A4900 ASSEMBLY (PARA 2-61). 4 CH 2-1 2-68 REPLACE A3000 ASSEMBLY (PARA 2-43).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-4 + 16 vdc Circuit Troubleshooting (Sheet 2 of 4) EL1AT163 DISCONNECT P2001 FROM J2001. SEE ILLUSTRATION, SH 4. REPLACE A5500 ASSEMBLY (PARA 2-44). 4 CH 2-1 REPLACE A4500 ASSEMBLY (PARA 2-49). REPLACE A2000 ASSEMBLY (PARA 2-70).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-4 + 16 vdc Circuit Troubleshooting (Sheet 3 of 4) NOTES 2. See FO-11 for power distribution wiring. DISCONNECT P4001 FROM PINS ON A4000 ASSEMBLY. SEE ILLUSTRATION. REPLACE A1000 ASSEMBLY (PARA 2-68). ALINE (PARA 2-35). 4 CH 2-1 REPLACE A4000 ASSEMBLY (PARA 2-41).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-5 No Audio Output Troubleshooting (Sheet 1 of 8) CONNECT EQUIPMENT AS SHOWN IN AUDIO POWER OUTPUT PERFORMANCE TEST (PARA 2-5). EL1AT199 WITH APPROXIMATELY 2.5V INPUT SIGNAL, CHECK FOR APPROXIMATE LY0.15 VAC OUTPUT AT TP4003. SEE ILLUSTRATION, SH 7. PERFORM AUDIO POWER OUTPUT AND DISTORTION PERFORMANCE TEST (PARA 2-5). REPLACE IF. AMPLIFIER LIMITER AND DISCRIMINATOR MODULE A4200 (PARA 2-41). CHECK VOLTAGE AT TP4007 ON IF.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-5 No Audio Output Troubleshooting (Sheet 2 of 8) CHECK AC VOLTAGE AT TP5513 ON THE RECEIVER AUDIO AMPLIFIER ASSEMBLY. SEE ILLUSTRATION, SH 7. REPLACE AUDIO AMPLIFIER MODULE A5400 (PARA 2-44). ADJUST (PARA 2-30). CHECK AC VOLTAGE AT TP5509. SEE ILLUSTRA. TION, SH 7. REPEAT AUDIO POWER OUTPUT AND DISTORTION PERFORMANCE TEST (PARA 2-5). REPLACE AUDIO FILTER FL5501 (PARA 2-44). CHECK AC VOLTAGE AT TP5504. SEE ILLUSTRATION, SH 7.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-5 No Audio Output Troubleshooting (Sheet 3 of 8) CHECK CONTINUITY OF RELAY K4502. IF DEFECTIVE REPLACE (PARA 2-65). REPEAT AUDIO POWER OUTPUT AND DISTORTION PERFORMANCE TEST (PARA 2-5). CHECK CONTINUITY OF RELAY K4501. IF DEFECTIVE REPLACE (PARA 2-65). REPLACE REFLECTOMETER AND SIDETONE GATE DETECTOR (PARA 2-63). DISCONNECT P4505 FROM J4505 AND CONNECT THE AN/URM-1030 OUTPUT TO J4505. SEE ILLUSTRATION, SH 8.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-5 No Audio Output Troubleshooting (Sheet 4 of 8) REPLACE MODULES A1100 THRU A1500 (PARA 2-52). REMOVE A4200 AND INJECT 0.15 VOLTS, 1000 Hz, AT TP4003. SEE ILLUSTRATION, SH 7. DISCONNECT P4902 FROM J4902 ON IF. ATTENUATOR AND APPLY AN/U RM-103 OUTPUT TO P4902. SEE ILLUSTRATION, SH 8. ALINE A1000 ASSEMBLY (PARA 2-35). ADJUST AN/URM-103 FOR 100 MILLIVOLTS OUTPUT AND CHECK FOR ABOUT 0.1 VAC AT TP4009 ON IF. AMPLIFIER ASSEMBLY.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-5 No Audio Output Troubleshooting (Sheet 5 of 8) REPLACE 1ST AND 2ND IF. AMPLIFIER MODULE A4100 (PARA 2-41). CHECK AC VOLTAGE AT TP4004 ON IF. AMPLIFIER ASSEMBLY. SEE lLLUSTRATION, SH 7. REPLACE FIRST AND SECOND IF. AMPLIFIER MODULE A4100 (PARA 2-41). REPEAT AUDIO POWER OUTPUT AND DISTORTION PERFORMANCE TEST (PARA 2-5). REPLACE 11.5 MHz CRYSTAL FILTER FL4002 (PARA 2-41). REPLACE LIMITER AND DISCRIMINATOR MODULE A4200 (PARA 2-41).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-5 No Audio Output Troubleshooting (Sheet 6 of 8) REPLACE RECEIVER SQUELCH AMPLIFIER MODULE A5200 (PARA 2-44). PREFORM CARRIER SQUELCH ADJUSTMENT (PARA 2-31). REPLACE RELAY K5502 (PARA 2-44). PERFORM CARRIER SQUELCH ADJUSTMENT (PARA 2-31). REPLACE SQUELCH FILTER MODULE A5300 (PARA 2-44). PERFORM CARRIER SQUELCH ADJUSTMENT (PARA 2-31). PERFORM AUDIO POWER OUTPUT AND DISTORTION TEST (PARA 2-5).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-6 Audio Power Troubleshooting CONNECT EQUIPMENT AS SHOWN IN AUDIO POWER OUTPUT PERFORMANCE TEST (PARA 2-5). PERFORM AUDIO LEVEL ADJUSTMENT (PARA 2-30). PERFORM AUDIO POWER OUTPUT AND DISTORTION PERFORMANCE TEST (PARA 2-5). SEE TROUBLESHOOTING CHART 2-5.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-7 Audio Distortion Troubleshooting (Sheet 1 of 2) PERFORM AUDIO LEVEL ADJUSTMENT (PARA 2-30). THEN PERFORM AUDIO POWER OUTPUT PERFORMANCE TEST (PARA 2-5). CHECK DISTORTION AT TP4007 ON IF. AMPLIFIER ASSEMBLY. SEE ILLUSTRATION, SH 2. REPLACE AUDIO AMPLIFIER MODULE A5400 (PARA 2-44). ADJUST (PARA 2-30). REPLACE AUDIO AND SQUELCH PREAMPLIFIER MODULE A4300 (PARA 2-41). PER FORM AUDIO POWER OUTPUT AND DISTORTION PERFORMANCE TEST (PARA 7-5).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-8 Poor Audio Response Troubleshooting (Sheet 1 of 2) CONNECT EQUIPMENT AS SHOWN IN AUDIO-FREQUENCY RESPONSE PERFORMANCE TEST (PARA 2-6). REPLACE AUDIO AND SQUELCH PREAMPLIFIER MODULE A4300 (PARA 2-41). CONNECT THE TS-723B/U TO TEST POINT TP4007 ON IF. AMPLIFIER ASSEMBLY A4000. SEE ILLUSTRATION, SH 2. PERFORM AUDIOFREQUENCY RESPONSE AND FRONT PANEL METER PERFORMANCE TEST (PARA 2-6). REPLACE AUDIO AMPLIFIER MODULE A5400 (PARA 2-44).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-9 Poor Sensitivity Troubleshooting (Sheet 1 of 2) PERFORM RECEIVER SENSITIVITY ADJUSTMENT (PARA 2-35). DISCONNECT P4901 FROM J4901 ON IF. ATTENUATOR A4900. CONNECT THE AN/ URM-103 OUTPUT TO J4901. SEE ILLUSTRATION, SH 2. REPEAT RECEIVER SENSITIVITY, QUIETING AND LIMITING PERFORMANCE TEST (PARA 2-7). ALINE VHF TUNER ASSEMBLY A1000 (PARA 2-35). DISCONNECT P4902 FROM J4902 ON IF. ATTENUATOR WITH AN/URM-103 SET TO 11.5 MHz, 0.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-10 Maximum Signal Plus Noise-to-Noise Ratio Troubleshooting CONNECT EQUIPMENT AS SHOWN IN MAXIMUM SIGNAL PERFORMANCE TEST (PARA 2-8). REMOVE AUDIO AND SQUELCH PREAMPLIFIER MODULE A4300 (PARA 2-41). INSTALL A NEW MODULE A4300 (PARA 2-41). REMOVE SQUELCH AMPLIFIER MODULE A5200 (PARA 2-44). PERFORM MAXIMUM SIGNAL PLUS NOISE-TO-NOISE RATlO PERFORMANCE TEST (PARA 2-8). PERFORM ALINIMENTS (PARA 2-31 AND 2-33).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-11 Carrier Squelch Sensitivity Troubleshooting PERFORM CARRIER SQUELCH ADJUSTMENT (PARA 2-31). PERFORM CARRIER SQUELCH SENSITIVITY PERFORMANCE TEST (PARA 2-9). REPLACE RECEIVER SQUELCH AMPLIFIER MODULE A5200 (PARA 2-44) REPLACE RELAY K5502 (PARA 2-44) AND ADJUST (PARA 2-31). PERFORM CARRIER SQUELCH ADJUSTMENT (PARA 2-31). PERFORM CARRIER SQUELCH SENSITIVITY PERFORMANCE TEST (PARA 2-9).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-12 Tone Squelch Sensitivity Troubleshooting (Sheet 1 of 2) NOTES 1. After replacing each unit, perform Tone Squelch Sensitivity Test (para 2-10) and if trouble is not corrected, replace units in sequence listed in flow chart. 2. If replacing module A5200, adjust in accordance with paragraph 2-33, then do Performance Test (para 2-10). PER FORM TONE SQUELCH ADJUSTMENT (PARA 2-33). CHECK FOR CONTINUITY BETWEEN PINS A1 AND A2 OF RELAY K5505.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-13 Transmitter Power Output (HI) Troubleshooting (Sheet 1 of 3) NOTES Frequency should be within ± 350 KHz of the control unit setting from 30.00 to 52.95 MHz and within ± 450 KHz for frequencies at 53.00 to 75.95 MHz. CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11). EL1AT208 REPLACE MODULE A6300 ON A6000 ASSEMBLY (PARA 2-48). PERFORM TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-13 Transmitter Power Output (HI) Troubleshooting (Sheet 2 of 3) REPLACE MODULE A6400 ON A6000 ASSEMBLY (PARA 248). PERFORM TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11). EL1AT209 LOCATE OPEN CIRCUIT AND REPAIR, SEE FO-12. IF HI-LO SWITCH IS DEFECTIVE, REPLACE (PARA 2-57). PERFORM TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11). 2-92 PERFORM TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-13 Transmitter Power Output (HI) Troubleshooting (Sheet 3 of 3) ALINE A6500 (PARA 2-28). REPLACE RF AMPLIFIER ASSEMBLY A6500 (PARA 2-58). PERFORM TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11). ALINE MODULE A6500 (PARA 2-28).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-14 Transmitter Power Output (LO) Troubleshooting CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-117). EL1AT209 LOCATE DEFECTIVE CIRCUIT AND REPAIR. SEE FO12. IF HI-LO SWITCH IS DEFECTIVE, REPLACE (PARA 2-57). 2-94 PERFORM TRANSMITTER POWER OUTPUT PER FORMANCE TEST (PARA 2-11).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-15 Transmitter Tone Modulation Troubleshooting (Sheet 1 of 2) CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER TONE MODULATION PERFORMANCE TEST (PARA 2-12). PER FORM TEST PROCEDURE OF TRANSMITTER DEVIATION NARROW BAND PERFORMANCE TEST. (PARA 2-13). PLACE TRANSMIT SWITCH ON TEST SET TO ON. CHECK DC VOLTAGE AT TP8706. SEE ILLUSTRATION, SH 2. PERFORM 150 Hz TONE MODULATION FREQUENCY AND DEVIATION ADJUSTMENT (PARA 2-32).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-15 Transmitter Tone Modulation Troubleshooting (Sheet 2 of 2) REPLACE 11.5 MHz MODULATOR MODULE A8100 (PARA 2-45). PERFORM TRANSMITTER TONE MODULATION PERFORMANCE TEST (PARA 2-12). 2-96 CHECK +16 VDC DISTRIBUTION AND REPAIR SEE FO-11. REPLACE AUDIO MIXER A8600 (PARA 2-45).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-16 Transmitter Deviation Narrow Band Troubleshooting (Sheet 1 of 2) CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER DEVIATION NARROW BAND PERFORMANCE TEST (PARA 2-13). PERFORM TRANSMITTER TONE MODULATION PERFORMANCE TEST (PARA 2-12). PERFORM NARROW BAND DEVIATION ADJUSTMENT (PARA 2-34). PERFORM DEVIATION NARROW BAND PERFORMANCE TEST (PARA 2-13). REFER TO TROUBLESHOOTING CHART 2-15.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-17 Transmitter Distortion Narrow Band Troubleshooting (Sheet 1 of 2) CONNECT EQUIPMENT AS SHOWN IN DISTORTION NARROW BAND PER FORMANCE TEST (PARA 2-14). CHECK DC VOLTAGE AT TP8701. SEE ILLUSTRATION, SH 2. CHECK DC VOLTAGE AT TP8706 ON AMPLIFIER MODULATOR ASSEMBLY A8700. SEE ILLUSTRATION, SH 2. REPLACE AUDIO MIXER MODULE A8600 (PARA 2-14). CHECK +16 VDC DISTRIBU TION AND REPAIR. SEE FO-11.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-18 Maximum Signal Plus Noise-to-Noise Ratio Troubleshooting (Sheet 1 of 2) CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER SIGNAL PLUS NOISE-TONOISE RATIO PERFORMANCE TEST (PARA 2-15). REPLACE 11.5 MHz MODULATOR MODULE A8100 (PARA 2-45). PERFORM TRANSMITTER SIGNAL PLUS NOISE-TONOISE RATIO PERFORMANCE TEST (PARA 2-15). SHORT PIN 6 0F J8701 TO GROUND. SEE lLLUSTRATION, SH 2.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-18 Maximum Signal Plus Noise-to-Noise Ratio Troubleshooting (Sheet 2 of 2) CHECK WIRE BETWEEN J8701, PIN 6, AND TB9601 PIN 10. IF DEFECTIVE, REPAIR. SEE ILLUSTRATION AND FO-12. CHECK WIRING BETWEEN TB9601, PIN 5, (SEE ILLUSTRATION) AND RELAY K9606, PIN 5, IF DEFECTIVE, REPAIR, SEE FO-12. PERFORM TRANSMITTER SIGNAL PLUS NOISE-TONOISE RATIO PERFORMANCE TEST (PARA 2-15).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-19 Transmitter Frequency Stability Troubleshooting (Sheet 1 of 5) NOTES 1. Set control unit to frequencies used in Frequency Stability Performance Test (para 2-16). 2. Does the total frequency error at P3301 and P3701 exceed 3.5 KHz? CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER FREQUENCY STABILITY PERFORMANCE TEST (PARA 2-16). 3. Is measured frequency more than ± 3.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-19 Transmitter Frequency Stability Troubleshooting (Sheet 2 of 5) DISCONNECT P3002 FROM J3002 AND APPLY A GROUND TO PIN 2 ON THE VHF TUNER. SEE ILLUSTRATIONS ON SH 4 AND SH 5. REPLACE VHF TUNER OSCILLATOR BOARD ASSEMBLY A1500 (PARA 2-52). ALINE MODULE A1500 (PARA 2-36). PERFORM TRANSMITTER FREQUENCY STABILITY PERFORMANCE TEST (PARA 2-16). CHECK RESISTANCE TO GROUND AT TP3001. SEE ILLUSTRATION, SH 5. 2-104 CHECK RELAY K3001 AND WIRING.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-19 Transmitter Frequency Stability Troubleshooting (Sheet 3 of 5) REPLACE CRYSTAL REFERENCE SYSTEM ASSEMBLY A3000 (PARA 2-43). PEFORM TRANSMITTER FREQUENCY STABILITY PEFORMANCE TEST (PARA 2-16). INJECT THE FREQUENCIES LISTED IN TABLE A AT A 250 MILLIVOLT LEVEL. MEASURE OUTPUT AT TP3001. SEE ILLUSTRATION SH 5. IF DC VOLTAGES ARE NOT OBTAINED AS SHOWN IN TABE A, REPLACE ASSEMBLY A3000 (PARA 2-43). TABLE A FREQUENCY (MHz) 42.050 42.250 42.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-19 Transmitter Frequency Stability Troubleshooting (Sheet 4 of 5) TABLE B Last two digits of freq sel 00 05 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 2-106 Interpolation osc Xtal Y2006 Y2007 Y2007 Y2008 Y2008 Y2009 Y2009 Y2010 Y2010 Y2005 Y2005 Y2004 Y2004 Y2003 Y2003 Y2002 Y2002 Y2001 Y2001 Y2006 Freq (MHz) 46.850 46.950 46.950 47.050 47.050 47.150 47.150 47.250 47.250 47.350 47.350 47.450 47.450 47.550 47.550 47.650 47.650 47.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-20 Automatic Frequency Selection and Channel Changing Tone Troubleshooting CONNECT EQUIPMENT AS SHOWN IN PERFORMANCE TEST IN PARA 2-17. CHECK RELAY K9605 AND WIRING. SEE FO-12. REPLACE GEARBOX ASSEMBLY A9700 (PARA 2-71). DO PERFORMANCE TEST IN PARA 2-17. 2-108 ALINE A9700 (PARA 2-29). REPLACE MODULE A5400 (PARA 2-44).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-21 Transmitter Sidetone Troubleshooting CONNECT EQUIPMENT AS SHOWN IN TRANSMITTER SIDETONE PERFORMANCE TEST (PARA 2-18). PERFORM TRANSMITTER POWER OUTPUT PERFORMANCE TEST (PARA 2-11). CHECK WIRING BETWEEN REFLECTOMETER AND SIDETONE DETECTOR Z4502, PIN 4, CONNECTOR P5501, PIN 17, AND RELAY K5501, PIN A1. SEE FO-12. REPAIR WIRING OR, IF DEFECTIVE REPLACE RELAY K5501 (PARA 2-44).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-22 Homing Flag Indication Troubleshooting CONNECT EQUIPMENT AS SHOWN IN HOMING SENSITIVITY PERFORMANCE TEST (PARA 2-19). REPLACE SQUELCH RELAY K5502 (PARA 2-44). REPLACE SQUELCH AMPLlFIER MODULE A5200 (PARA 2-44). CHECK FOR CONTINUITY BETWEEN PINS 5 AND 6 OF CONNECTOR P5501. SEE ILLUSTRATION OF P5501, AND SEE FO-12 FOR PIN LOCATION. PERFORM STEPS 1 AND 2 OF HOMING SENSITIVITY PERFORMANCE TEST (PARA 2-19).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-23 Homing Needle Indication Troubleshooting (Sheet 1 of 3) CONNECT EQUIPMENT AS SHOWN IN HOMING SENSITIVITY PERFORMANCE TEST (PARA 2-19). CONNECT OSCILLOSCOPE AN/USM-281A TO TP4809 AND CHECK FOR 1.0 VOLTS PEAK-TO-PEAK AT 100 Hz. SEE ILLUSTRATION, SH 3. CHECK DC VOLTAGE AT TP4803. SEE ILLUSTRATION, SH 3. PERFORM HOMING ADJUSTMENT (PARA 2-37). CONNECT OSCILLOSCOPE AN/USM-281A TO TP4501 AND CHECK FOR 1.0 VOLTS PEAK-TO-PEAK AT 100 Hz.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-23 Homing Needle Indication Troubleshooting (Sheet 2 of 3) CHECK FOR CONTINUITY BETWEEN TP4809 AND PIN 9 OF CONNECTOR P4801, SEE ILLUSTRATION, SH 3 AND FO-12 FOR PIN LOCATION. CHECK FOR CONTINUITY BETWEEN PIN 9 OF CONNECTOR P4801 AND TP4501. SEE ILLUSTRATION, SH 3 AND F0-12. 2-112 ADJUST R2106 FOR A READING OF +16 VDC. SEE ILLUSTRATION. IF ADJUSTMENT IS NOT POSSIBLE, REPLACE A2100 (PARA 2-50).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 1 of 12) NOTE Use the troubleshooting table to isolate and correct faults in the control unit. The troubleshooting table is used in the following manner. 1. Go to malfunction item number referred to in performance test. 2. Perform test or inspection. 3. If corrective action is taken, repeat performance test. 4. If no corrective action is taken, go to next step. 5. Repeat test procedure.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 2 of 12) MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 5. Speaker noise present/not present (SQUELCH switch at CARR). Check for short circuit between main connector J9101 pin V and ground. (See FO-13.) Replace switch S9106 (para 2-78). 6. Speaker noise not present (SQUELCH switch at DIS). Check for infinite resistance between main connector J9101 pin V and ground. (See FO-13.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 3 of 12) MALFUNCTION TEST OR INSPECTION Corrective ACTION 10. Gearbox BAND SWITCH does not activate at 53 MHz. Check continuity between main connector J9101 pin J and ground. (See FO-13.) Repair wiring or replace frequency selector switches S9101 (para 2-83) or S9102 (para 2-64).
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 4 of 12) CONTROL UNIT RESISTANCE TABLES The charts in this section list resistance readings that should be observed at each pin of J9101 for each control position. All measurements are made with the ME-26D/U. Resistances are in ohms. VOL control R9103 is set fully clockwise; all other switches are set as indicated. MODE SWITCH at OFF, SQUELCH switch at DIS, and frequency selectors at 30.00.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 5 of 12) MODE SWITCH at T/R, SEQUELCH switch at DIS. FROM PIN X,FF,HH,MM,NN,t,s,u, PP,w,C,a,A,Y GG q JJ y d e,f,F b,Z,V RESISTANCE TO PIN All other pins DD v N x KK,B E,D,C Ground Inf 27 k 0 0 (VOL fully clockwise) 0 0 0 0 MODE SWITCH at T/R, SQUELCH switch at CARR.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 6 of 12) MODE SWITCH at RETRAN, SQUELCH switch at DIS. FROM PIN X,FF,HH,MM,NN,t,s,a,Y GG q v JJ PP KK w KK y x JJ e,f,F b,Z,v TO PIN All other pins DD v u N KK B KK d x c A E,D,C Ground RESISTANCE Inf 27 k 0 0 0 (VOL fully clockwise) 0 0 0 0 0 510 0 0 0 MODE SWITCH at RETRAN, SQUELCH switch at CARR.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 7 of 12) MODE SWITCH at RETRAN, SQUELCH switch at TONE. FROM PIN x GG FF,MM,NN,t,s,a,V HH q v JJ PP y w e,f,F x b,Z TO PIN Ground DD All other pins Y v u N KK,B x KK,d E,D,C c Ground RESISTANCE 0 27 k Inf 0 0 0 0 (VOL fully clockwise) 0 0 0 0 510 0 MODE SWITCH at HOME, SQUELCH switch at DIS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 8 of 12) MODE SWITCH at HOME, SQUELCH switch at CARR. FROM PIN X,HH,PP,U,A,w,a,V,c GG DD e,f,F FF MM t q JJ y d b,Z TO PIN All other pins DD e,f,F DD,E,D,C Y NN s v N x KK,B Ground RESISTANCE Inf 27 k Inf 0 0 0 0 0 0 (VOL fully clockwise) 0 0 0 MODE SWITCH at HOME, SQUELCH switch at TONE.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS. (CONT) CHART 2-24 Control Unit Troubleshooting (Sheet 9 of 12) FREQUENCY SELECTION CODE TABLES The tables in this section indicate the pins of J9101 that are grounded and the pins that are not grounded for each setting of the frequency selector switches. The grounded pins are indicated by zero resistance in the tables, and the ungrounded pins by INF (infinite) resistance. Pin G is grounded for all frequency settings from 30.00 to 52.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 2-26. TROUBLESHOOTING CHARTS.
TM 11-5820-670-30 Section IV ALINEMENT AND ADJUSTMENT PROCEDURES Subject General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rf Amplifier Assembly A6500 Alinement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gearbox Assembly A9700 Alinement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 2-28. RF AMPLIFIER ASSEMBLY A6500 ALINEMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Multimeter AN/USM-223 Power Supply PP-2953/U Receiver-Transmitter AN/ARC-131 (known to be operating properly) Wattmeter AN/URM-120 All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. NOTE Install rf amplifier assembly to be alined in a known good receiver-transmitter.
TM 11-5820-670-30 2-28. RF AMPLIFIER ASSEMBLY A6500 ALINEMENT. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING CONTROL UNIT Mode Selector SQUELCH FREQ sel T/R DIS 65.00 MHz TS-2575/ARC-131 HI/LO AGC switch HI OFF ALINEMENT PROCEDURE NOTE During alinement, maintain at least 12 to 15 watts output power.
TM 11-5820-670-30 2-28. RF AMPLIFIER ASSEMBLY A6500 ALINEMENT. (CONT) 1. Place the TRANSMIT switch on test set to ON position. 2. Adjust C6512 for minimum dc current as monitored at TP101 (+) and TP102 (-) on test set. 3. Adjust C6504 for maximum power output. CAUTION When adjusting the variable inductors in the following steps, be careful not to overadjust as small tuning cores may drop through bottom of inductor. 4. Set frequency selectors on control unit to 53.00 MHz. 5.
TM 11-5820-670-30 2-29. GEARBOX ASSEMBLY A9700 ALINEMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Power Supply PP-2953/U TEST SETUP Connect equipment as shown in test setup diagram. Turn on equipment and allow 5 minutes for warmup. ALINEMENT PROCEDURE 1. Place test set +28 vdc ON-OFF switch to ON, and adjust power supply output for +27.5 vdc. 2. Place test set +28 vdc ON-OFF switch to OFF, and power supply power switch to OFF. 3.
TM 11-5820-670-30 2-29. GEARBOX ASSEMBLY A9700 ALINEMENT. (CONT) 7. Using hex wrench, loosen setscrews on all three coupling collars. 8. Install coupler alinement tool, TL-758/ARC-131 on all couplers. 9. Move couplers to allow coupler alinement tool to drop into coupler slot. 10. Using hex wrench, tighten all setscrews. 11. Remove coupler alinement tool. 12. Install modules removed in step 3.
TM 11-5820-670-30 2-30. AUDIO LEVEL ADJUSTMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Signal Generator AN/URM-127 Spectrum Analyzer TS-723 A/U Fuseholder MX-1730/U Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT141 INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table.
TM 11-5820-670-30 2-30. AUDIO LEVEL ADJUSTMENT. (CONT) CONTROL AND SWITCH SETTINGS EQUIPMENT CONTROL OR SWITCH POSITION/SETTING TS-2575/ARC-131 Mode Switch VOL SQUELCH FREQ sel T/R fully clockwise DIS 60.05 AN/URM-127 amplitude control output frequency 0 1000 Hz AN/URM-103 Function selector output EXT MOD 10 microvolt ADJUSTMENT PROCEDURE 1. 2. 3. 4. Adjust AN/URM-127 for 8 kHz deviation as indicated on AN/URM-103 modulation meter. Set TS-723A/U function switch to METER.
TM 11-5820-670-30 2-31. CARRIER SQUELCH ADJUSTMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Signal Generator AN/URM-127 Fuseholder MX-1730/U Power Supply PP-2953/U Spectrum Analyzer TS-723A/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-31. CARRIER SQUELCH ADJUSTMENT. (CONT) ADJUSTMENT PROCEDURE 1. On TS-2575/ARC-131, place the +28 VDC ON – OFF switch to ON. EL1AT239 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. Set carrier squelch potentiometer R5216 on A5500 assembly fully clockwise. Set RT-823/ARC-131 SQ ADJ control fully clockwise. Set control unit mode switch to T/R. VOL control fully clockwise, SQUELCH switch to DIS, and frequency selectors to 60.05 MHz.
TM 11-5820-670-30 2-32. 150 Hz TONE MODULATION FREQUENCY AND DEVIATION ADJUSTMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Electronic Counter Digital Readout AN/USM-207 Modulation Meter ME-57/U Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT148 ADJUSTMENT PROCEDURE 1. Place +28 VDC ON-OFF switch on TS-2575/ARC-131 to ON. 2.
TM 11-5820-670-30 2-32. 150 Hz TONE MODULATION FREQUENCY AND DEVIATION ADJUSTMENT. (CONT) EL1AT242 6. Adjust potentiometer R8609 on module A8600 fully clockwise. 7. Place TRANSMIT switch on test set to ON. EL1AT239 8. Adjust R5301 on A5500 assembly for 150 ± 2 Hz indication on frequency meter AN/USM-207. 9. Adjust potentiometer R8609 on module A8600 for 3 kHz deviation as indicated on deviation meter.
TM 11-5820-670-30 2-33. TONE SQUELCH ADJUSTMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Signal Generator AN/URM-127 Power Supply PP-2953/U Fuseholder MX-1730/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes warmup.
TM 11-5820-670-30 2-33. TONE SQUELCH ADJUSTMENT. (CONT) ADJUSTMENT PROCEDURE Place +28 VDC ON-OFF switch on test set to ON. Set control unit mode switch to T/R, VOL control fully clockwise, SQUELCH switch to TONE, and frequency selectors to 60.05 MHz. 3. Set Signal Generator AN/URM-127 amplitude control to 0, and adjust output frequency to 150 Hz. Set Signal Generator AN/URM-103 FUNCTION selector switch to EXT MOD, and adjust for a 10 4. microvolt output at 60.05 MHz. 5.
TM 11-5820-670-30 2-34. NARROW BAND DEVIATION ADJUSTMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Modulation Meter ME-57/U Signal Generator AN/URM-127 Voltmeter ME-30E/U Power Supply PP-2953/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup.
TM 11-5820-670-30 2-34. NARROW BAND DEVIATION ADJUSTMENT. (CONT) INITIAL EQUIPMENT CONTROL SETTINGS Set equipment controls as indicated in the following table. CONTROL AND SWITCH SETTINGS POSITION/SETTING EQUIPMENT CONTROL OR SWITCH TS-2575/ARC-131 MODE SWITCH VOL SQUELCH switch FREQ sel WIDE BAND-NAR BAND TRANSMIT switch T/R fully clockwise DIS 60.05 MHz WIDE BAND OFF AN/URM-127 OUTPUT FREQUENCY AMPLITUDE CONTROL 1000 Hz 0.39 volt as observed on ME-30E/U ADJUSTMENT PROCEDURE 1.
TM 11-5820-670-30 RECEIVER SENSITIVITY ADJUSTMENTS. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Oscilloscope AN/USM-281A Power Supply PP-2953/U Fuseholder MX-1730/U Spectrum Analyzer TS-723A/U. All cables are part of MK-103/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT243 ADJUSTMENT PROCEDURE 1. Set control unit C-7088/ARC-131 mode switch on test set to OFF. 2.
TM 11-5820-670-30 2-35. RECEIVER SENSITIVITY ADJUSTMENTS. (CONT) EL1AT244 6. Using board extractor, remove A1100 module from its mount. Inspect A-B board switch for a broken post. If post is broken, replace module. Clean contacts by rubbing with a pencil eraser. Ensure grounding posts are in direct contact with A1000 can. CAUTION If post on A-B board switch does not fit in fork, the post will be broken the first time band switch actuator changes position, and receiver will not work. 7.
TM 11-5820-670-30 2-35. RECEIVER SENSITIVITY ADJUSTMENTS. (CONT) ADJUSTMENT PROCEDURE (CONT) 9. Repeat step 5, and if signal still drops off, run signal generator up and down band to determine if local oscillator is off frequency. This can be determined by hearing an audio signal at a frequency other than 30 MHz. If this proves to be the case, perform local oscillator alinement (para 2-36), then repeat step 5. If signal drops off prior to 0.5 microvolt, perform steps 10 through 14. EL1AT245 10.
TM 11-5820-670-30 2-35. RECEIVER SENSITIVITY ADJUSTMENTS. (CONT) 13. Change frequency to 75.00 MHz and repeat step 10, tuning 65.00 and 75.00 MHz coils using a nonmetallic alinement tool. 14. With frequency at 75.00 MHz, repeat step 10, tuning the 65.00 and 75.00 MHz capacitors using a small jeweler’s screwdriver. 15. If tests are still unsuccessful, substitute boards as necessary and repeat alinement procedures, or refer radio to higher level of maintenance. EL1AT246 16.
TM 11-5820-670-30 2-36. LOCAL OSCILLATOR ALINEMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Power Supply PP-2953/U Frequency Meter AN/USM-207 T-Connector All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. EL1AT247 ALINEMENT PROCEDURE 1. Set control unit mode switch to T/R. 2. When RT-823/ARC-131 is on a frequency range of 30.00 to 52.
TM 11-5820-670-30 2-36. LOCAL OSCILLATOR ALINEMENT. (CONT) CONTROL UNIT FREQUENCY (MHz) A BAND B BAND 30.00 42.00 52.00 53.00 65.00 75.00 FREQUENCY COUNTER READOUT (MHz) 41.50 ± 0.002 53.50 ± 0.002 63.50 ± 0.002 3. If frequency reading is not within tolerances of table, perform the following adjustments. 4. Remove J1004 from- P1004 on receiver-transmitter. This removes lock-in. 5. At 30.00 MHz, adjust L1502 until reading on frequency counter is 41.50 ± 0.002 MHz. Switch to 42.
TM 11-5820-670-30 2-37. HOMING ADJUSTMENT. TEST EQUIPMENT AND MATERIALS Maintenance Kit MK-1035/ARC-131 Signal Generator AN/URM-103 Power Signal PP-2953/U Fuseholder MX-1730/U All cables are part of MK-1035/ARC TEST SETUP Connect equipment as shown in test setup diagram. Turn on all equipment and allow at least 5 minutes for warmup. ADJUSTMENT PROCEDURE 1. Set control unit mode switch to HOME, SQUELCH switch to CARR, and frequency selectors to 31.00 MHz. 2. Set test set LEFT and RIGHT HOMER ATTEN to 0 db.
TM 11-5820-670-30 2-37. HOMING ADJUSTMENT. (CONT) EL1AT249 4. Adjust vertical needle adjust potentiometer R4805, located on homer-detector amplifier assembly for a center-scale indication on homing indicator. 5. Vary signal generator output from minimum signal to 10 microvolt. Flags on homing indicator should disappear when signal generator output is 1.2 microvolt or less; vertical needle should stay centered ( ± 1/8 inch). 6.
TM 11-5820-670-30 Section V REPAIR AND REPLACEMENT PROCEDURES Subject Para Page General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-38 2-151 Receiver-Transmitter, RT-823/ARC-131 RT Case Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 Subject Control Unit C-7088/ARC-131 Front Panel Knobs Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Front Panel Dial Mask Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Light Panel Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 2-39. RT CASE REPLACEMENT. MATERIALS/PARTS: Case, receiver-transmitter (P/N SMD619940) REMOVAL 1. Using screwdriver, loosen two turn-lock fasteners (1). 2. Carefully pull case (2) off chassis. INSTALLATION CAUTION Care must be taken when performing next step to prevent pinching or breaking wires. 1. Install case (2) on chassis. 2. Using screwdriver, tighten two turn-lock fasteners (1).
TM 11-5820-670-30 2-40. HOMING MODULE A4600 REPLACEMENT. MATERIALS/PARTS: Module, homing, A4800 (P/N SMD619582) PRELIMINARY PROCEDURE: Remove case (para 2-39). EL1AT002 REMOVAL 1. Using screwdriver, loosen two captive screws (1) and lower module (2). 2. Using screwdriver, loosen screw (3) and remove ground strap (4). 3. Using screwdriver, loosen two captive screws (5) and pull P4801 connector (6) free from J4801 connector (7). 4. Remove C-clip (8) from hinge pin (9), and remove hinge pin from hinge (10).
TM 11-5820-670-30 2-41. A4000 MODULES AND ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Amplifier assembly, if. A4100 (P/N SMC413726) Amplifier assembly, if. A4000 (P/N SME619985) Amplifier, frequency, audio, A4300 (P/N SMB413785) Discriminator, frequency, electrical, A4200 (P/N SMC413753) Filter, band-pass, FL4001 (P/N SMD413720) Filter, band-pass, FL4002 (P/N SMD413719) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, loosen two captive screws (1) and swing out assembly (2).
TM 11-5820-670-30 2-41. A4000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) NOTE Modules FL4001 and FL4002 are secured with locknuts. Steps 4 and 5 are typical for both modules. Note position of FL4002 module for 50 kHz or WIDE BAND operation mode. 4. Using wrench, remove locknuts (5) and IT Iockwashers (6). 5. Carefully pull module (7) off board. 6. Using screwdriver, loosen two captive screws (8). 7. Carefully lift P4001 (9) off pins (10). 8. Disconnect blue wire (P4902) (11) from J4902. 9.
TM 11-5820-670-30 2-41. A4000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) INSTALLATION (CONT) NOTE Before installing FL4002 filter, establish whether a 50 kHz or WIDE BAND operation mode will be used. The position of FL4002 filter will depend on operation mode selected. See detail A for 50 KC operation mode and detail B for WIDE BAND operation mode. NOTE Modules FL4001 and FL4002 are secured with locknuts. Steps 3 and 4 are typical for both modules. Module location is stamped on board.
TM 11-5820-670-30 2-41. A4000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) 3. Position module (1) on board and install IT Iockwashers (2) and locknuts (3) on studs (4). CAUTION Care must be taken when performing next step to prevent damaging printed circuit board. Do not overtighten. 4. Using wrench, tighten locknuts (3). CAUTION Before installing modules, ensure pins are not bent. Straighten any bent pins. Extreme care must be taken not to damage pins.
TM 11-5820-670-30 2-41. A4000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) INSTALLATION (CONT) 7. Connect blue wire (P4902) (1) to J4902. CAUTION Care must be taken when performing next step to prevent damaging pins on assembly. 8. Position P4001 (2) on pins (3) and push into place. 9. Using screwdriver, tighten two captive screws (4). 10. Swing assembly (5) into position. 11. Using screwdriver, tighten two captive screws (6). FOLLOW-ON MAINTENANCE: Install case (para 2-39).
TM 11-5820-670-30 2-42. A9500 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Power supply assembly A9500 (P/N SME619765) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, remove three shouldered screws (1) and swing open assembly (2). 2. Using screwdriver, loosen two captive screws (3) and pull P9501 (4) free from J9501 (5). 3. Remove C-clip (6) from hinge pin (7). 4. Remove hinge pin (7) from hinge (8) and remove assembly (2). INSTALLATION 1.
TM 11-5820-670-30 2-43. A3000 MODULES AND ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Amplifier, interfrequency A3400 (P/N SMB413634) Crystal REF system assembly A3000 (P/N SMD619578) Discriminator assembly, phase A3700 (P/N SMB413699) Discriminator, elect.
TM 11-5820-670-30 2-43. A3000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) NOTE Modules A3100 through A3700 are secured with captive screws. Steps 3, 4, and 5 are typical for all modules. 3. Disconnect black wire (P3301) (3) from A3300 and red wire (P3701) from A3700 (4). 4. Using screwdriver, loosen captive screws (5). CAUTION To prevent damaging pins, do not twist module from side to side. 5. Carefully pull module (6) off board to release from pins.
TM 11-5820-670-30 2-43. A3000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) REMOVAL (CONT) EL1AT012 10. Using screwdriver, loosen two captive screws (1). 11. Carefully pull P3001 (2) off pins (3). Wires referenced in step 12 are located under assembly. 12. Disconnect black wire (P3301) from A3300 (4), red wire (P3701) from A3700 (5), green wire (P3002) from FL3002 (6), and all wires from wire clips. 13. Remove hinge pin (7) from hinge (8). 14. Remove assembly (9).
TM 11-5820-670-30 2-43. A3000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) NOTE Modules FL3001 through FL3005 are secured with locknuts and are soldered to printed circuit board. Steps 2, 3, and 4 are typical for all modules. Module location is stamped on board. 2. Position module (10) on board and install locknuts (11). 3. Using wrench, tighten locknuts (11). CAUTION Care must be taken when performing next step to prevent damaging printed circuit board. 4.
TM 11-5820-670-30 2-43. A3000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) INSTALLATION (CONT) CAUTION Before installing modules, ensure pins are not bent. Straighten any bent pins. Extreme care must be taken not to damage pins. Modules A3100 through A3700 are secured with captive screws. Steps 5 and 6 are typical for all modules. Module location is stamped on board. 5. Carefully position module (1) on pins (2) and push into place. 6. Using screwdriver, tighten captive screws (3). 7.
TM 11-5820-670-30 2-43. A3000 MODULES AND ASSEMBLY REPLACEMENT. (CONT) EL1AT015 CAUTION Extreme care must be taken when performing next step to prevent damaging pins on assembly. 8. 9. 10. 11. Carefully position P3001 (9) on pins (10) and push into place. Using screwdriver, tighten two captive screws (11). Lower assembly (12) into chassis. Using screwdriver, tighten one captive screw (13). FOLLOW-ON MAINTENANCE: Install case (para 2-39).
TM 11-5820-670-30 2-44. A5500 MODULES AND ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Amplifier, assembly, radio frequency, A5500 (P/N SMD619527) Amplifier, assembly, squelch, A5200 (P/N SMC413849) Filter, assembly, squelch, A5300 (P/N SMB413660) Filter, audiofrequency, FL5501 (P/N SMC413828) Receiver, assembly, audio amplifier, A5400 (P/N 715980-801) Relay, armature, K5501, K5503 through K5505 (P/N SMC413824) Relay, armature, K5502 (P/N SMC413823) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1.
TM 11-5820-670-30 2-44. A5500 MODULES AND ASSEMBLY REPLACE. (CONT) EL1AT017 NOTE Modules A5200 through A5400 are secured with captive screws. Steps 3 and 4 are typical for all modules. 3. Using screwdriver, loosen captive screws (5). To prevent damaging pins, do not twist module from side to side. 4. Carefully pull module (6) off board to release from pins. NOTE Filter module FL5001 is secured with locknuts and is solder to printed circuit board. 5. Using wrench, remove locknuts (7).
TM 11-5820-670-30 2-44. A5500 MODULES AND ASSEMBLY REPLACEMENT. (CONT) EL1AT018 EL1AT019 NOTE Relays K5501 through K5505 are held into sockets by a holddown clamp. Steps 8 and 9 are typical for all relays. 8. Using screwdriver, remove screw (1), Iockwasher (2), and holddown clamp (3). 9. Pull relay (4) out of socket (5). 10. Remove C-clip (6) from hinge pin (7). 11. Remove hinge pin (7) from hinge (8). 12. Remove assembly (9).
TM 11-5820-670-30 2-44. A5500 MODULES AND ASSEMBLY REPLACEMENT. (CONT) INSTALLATION 1. Position assembly (9) in hinge (8). 2. Install hinge pin (7) in hinge (8) from bottom. 3. Install C-clip (6) in hinge pin (7). NOTE If modules were not removed from assembly, proceed to step 12 for installation of assembly. Relays K5501 through K5505 are held into sockets by a holddown clamp. Steps 4, 5, and 6 are typical for all relays. Relay K5502 is P/N SMC413823 while all other relays are P/N SMC413824. 4.
TM 11-5820-670-30 2-44. A5500 MODULES AND ASSEMBLY REPLACEMENT. (CONT) INSTALLATION (CONT) EL1AT021 CAUTION Before installing modules, ensure pins on assembly are not bent. Straighten any bent pins. Extreme care must be taken not to damage pins. Modules A5200 through A5400 are secured with captive screws. Steps 10 and 11 are typical for all modules. 10. Carefully position module (1) on pins (2) and push into place. 11. Using screwdriver, tighten captive screws (3).
TM 11-5820-670-30 2-44. A5500 MODULES AND ASSEMBLY REPLACEMENT. (CONT) 12. 13. 14. 15. Position P5501 (4) on pins and push into place. Using screwdriver, tighten two captive screws (5). Swing assembly (6) to closed position. Using screwdriver, tighten two captive screws (7). FOLLOW-ON MAINTENANCE: Install case (para 2-39).
TM 11-5820-670-30 2-45. A8700 MODULES AND ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Amplifier, intermediate frequency, A8300 (P/N SMB414197) Amplifier modulator assembly, A8700 (P/N SMC819555) Filter, low-pass (P/N SM-C414172) Frequency generator, A8400 (P/N SMB374983) Mixer, audiofrequency, A8800 (P/N SM-C819588) Modulator assembly, A8100 (P/N SMD414176) Phase discriminator assembly, A8200 (P/N SMB414215) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1.
TM 11-5820-670-30 2-45. A8700 MODULES AND ASSEMBLY REPLACEMENT. (CONT) Modules A8100 through A8400 and A8600 are secured with captive screws. Steps 3 and 4 are typical for all modules. 3. Using screwdriver, loosen captive screws (5). CAUTION To prevent damage to pins, do not twist module from side to side. 4. Carefully pull module (6) off board to release from pins. NOTE Filter module is secured with locknuts and is soldered to printed circuit board. 5. Using wrench, remove locknuts (7).
TM 11-5820-670-30 2-45. A8700 MODULES AND ASSEMBLY REPLACEMENT. (CONT) REMOVAL (CONT) EL1AT025 8. Remove two C-clips (1) from hinge pins (2). 9. Remove two hinge pins (2) from hinges (3). 10. Using screwdriver, loosen two captive screws (4). 11. Carefully lift P8701 (5) off pins (6). 12. Remove assembly (7). INSTALLATION CAUTION Before installing assembly, ensure pins (6) are not bent. Straighten any bent pins. Extreme care must be taken not to damage pins. 1.
TM 11-5820-670-30 2-45. A8700 MODULES AND ASSEMBLY REPLACEMENT. (CONT) NOTE Filter module is secured with locknuts and is soldered to printed circuit board. Module location is stamped on board. 6. 7. Position module (8) on board and install locknuts (9). Using wrench, tighten locknuts (9). CAUTION Care must be taken when performing next step to prevent damaging printed circuit board. 8. Using soldering iron, solder pins (10) of module (8) to printed circuit board.
TM 11-5820-670-30 2-45. A8700 MODULES AND ASSEMBLY REPLACEMENT. (CONT) INSTALLATION (CONT) 11. Connect violet wire connector (1) to A8300 assembly (2). 12. Lower assembly (3) into chassis. 13. Using screwdriver, tighten two captive screws (4). NOTE Ensure handles on hinge pins (5) are down in a horizontal position so case can be installed. FOLLOW-ON MAINTENANCE: Install case (para 2-39).
TM 11-5820-670-30 2-46. A6600 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Amplifier assembly, isolation, A6000 (P/N SMD619913) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Disconnect yellow wire (P6601) (1) from J6601 (2). 2. Using two wrenches, disconnect yellow wire (P6003) (3) from screw connector (4). 3. Using screwdriver, remove two screws (5). 4. Disconnect black wire connector (6) from color-coded plug. 5. Disconnect orange wire connector (7) from color-coded plug. 6.
TM 11-5820-670-30 2-47. POWER SUPPLY CIRCUIT CARD REPLACEMENT. MATERIALS/PARTS: Circuit card assembly (P/N SMD619800) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, remove three shouldered screws (1) and swing open assembly (2). 2. Using wrench, remove four locknuts (3) and remove circuit card (4) from studs. 3. Turn circuit card (4) to gain access to wires on rear.
TM 11-5820-670-30 2-47. POWER SUPPLY CIRCUIT CARD REPLACEMENT. (CONT) 4. Using soldering iron, unsolder wires as shown in circuit card wiring table below. CIRCUIT CARD WIRING TABLE WIRE COLOR INDEX NO. WHT/ORG WHT/RED BLK WHT/BLU WHT RED WHT/GRN 5 6 7 8 9 10 11 5. Remove circuit card (4). INSTALLATION CAUTION Care must be taken when performing next step to prevent damaging printed circuit board. 1. Using soldering iron, solder wires as shown in circuit card wiring table above. 2.
TM 11-5820-670-30 2-48. A6300 AND A6400 MODULE REPLACEMENT. MATERIALS/PARTS: Circuit card assembly, A6300 (P/N SMD374993) Circuit card assembly, A6400 (P/N SMD374996) PRELIMINARY PROCEDURE: Remove case (para 2-39). EL1AT031 NOTE Modules A6300 and A6400 are housed within the A6000 assembly. REMOVAL 1. Disconnect gray wire (1) from J6001, brown wire (2) from J6002, and yellow wire (3) from J6003. 2. Using screwdriver, loosen two captive screws (4) and remove A6000 assembly cover (5).
TM 11-5820-670-30 2-48. A6300 AND A64Q0 MODULE REPLACEMENT. (CONT) INSTALLATION CAUTION Before installing modules A1100 through A1300, ensure band switch pin (7) on module (8) is positioned to mate with band switch actuating pawl (9) on A8000 assembly (10). 1. Carefully push modules (11) into place. NOTE Ensure spring contacts on modules make contact with partitions between modules. 2. Install A8000 assembly cover (12) on A6000 assembly. 3. Using screwdriver, tighten two captive screws (13). 4.
TM 11-5820-670-30 2-49. A4500 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Control, radio frequency, A4500 (P/N SMC619709) PRELIMINARY PROCEDURE: Remove case (para 2-39).
TM 11-5820-670-30 2-49. A4500 ASSEMBLY REPLACEMENT. (CONT) REMOVAL 1. Disconnect white wire (P1001) (1) from J1001, violet wire (P1003) (2) from J1003, and green wire (P1004) (3) from J1004 on A1000 assembly (4). 2. Disconnect orange wire (P4505) (5) from J4505 (6), violet wire (P4503) (7) from J4503 (8), and brown wire (9) from J4502 (10), on A4500 assembly (11). 3. Remove C-clip (12) from hinge pin (13). 4. Using screwdriver, loosen two captive screws (14) and lower A4500 assembly (11).
TM 11-5820-670-30 2-50. A2100 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Regulator assembly, voltage, A2100 (P/N SMD41457) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, loosen two captive screws (1) and lower A4600 assembly (2). 2. Disconnect nine wire connectors from A2100 assembly (3). 3. Using screwdriver, remove three screws (4) and remove A2100 assembly (3). INSTALLATION 1. Position A2100 assembly (3) on chassis and install three screws (4). 2.
TM 11-5820-670-30 2-51. FRONT PANEL REPLACEMENT. MATERIALS/PARTS: Panel, front PRELIMINARY PROCEDURE: Remove TEST METER, M9601 (para 2-53). Remove SQ DIS switch S9602 and XMTR TEST switch S9603 (para 2-54). REMOVAL 1. Using hex wrench, loosen setscrew (1) and remove TEST SWITCH knob (2). 2. Using wrench, remove two screw fasteners (3), Iockwashers (4), and flat washers (5), and move J4801 (6) out of way. 3. Remove front paneI (7). INSTALLATION 1. Position front panel (7) near chassis. 2.
TM 11-5820-670-30 2-52. A1100 THROUGH A1500 MODULE REPLACEMENT. MATERIALS/PARTS: Circuit card assembly, A1100 (P/N SMD 374983) Circuit card assembly, A1200 (P/N SMD 416370) Circuit card assembly, A1300 (P/N SMD 374990) Circuit card assembly, A1400 (P/N SMD 374986) Circuit card assembly, A1500 (P/N SMD 416384) PRELIMINARY PROCEDURE: Remove case (para 2-39). EL1AT038 REMOVAL NOTE Modules A1100 through A1500 are housed within the A1000 assembly. 1.
TM 11-5820-670-30 2-52. A1100 THROUGH A1500 MODULE REPLACEMENT. (CONT) NOTE A 1000 assembly cover is also used as a module puller to remove all modules. EL1AT040 2. Before removing A1100 module, disconnect white wire (3) from J1001; before removing A1400 module, disconnect violet wire (4) from J1003; before removing A1500 module, disconnect green wire (5) from J1004. 3. Using module puller, carefully remove modules (6).
TM 11-5820-670-30 2-52. A1100 THROUGH A1500 MODULE REPLACEMENT. (CONT) INSTALLATION - CONTINUED EL1AT042 1. Carefully push NOTE Ensure spring contacts on modules make contact with partitions between modules. 2. If modules A1100, A1400, or A1500 were removed, reconnect white wire (2) to J1001, violet wire (3) to J1003, or green wire (4) to J1004. EL1AT043 3. Install A1000 assembly cover (5) on A1000 assembly. 4. Using screwdriver, tighten four captive screws (6).
TM 11-5820-670-30 2-53. TEST METER M9601 REPLACEMENT. MATERIALS/PARTS: Meter, electrical indicating, dc, M9601 (P/N MS90212-24) PRELIMINARY PROCEDURE: Remove A8700 assembly (para 2-45). REMOVAL 1. Using screwdriver, remove two screws (1). 2. Using screwdriver and wrench, remove two screws (2), flat washers (3), and nuts (4). 3. Using hex wrench, loosen setscrew (5) and remove TEST SWITCH knob (6). NOTE Pull front panel away from chassis slightly to gain access to rear. 4.
TM 11-5820-670-30 2-54. SQ DIS SWITCH S9602 AND XMTR TEST SWITCH S9603 REPLACEMENT. MATERIALS/PARTS: Switch, push, S9602 and S9603 (P/N SMC 619497) PRELIMINARY PROCEDURE: Remove A8700 assembly (para 2-45). REMOVAL 1. Using screwdriver, remove two screws (1). 2. Using screwdriver and wrench, remove two screws (2), flat washers (3), and nuts (4). 3. Using hex wrench, loosen setscrew (5) and remove TEST SWITCH knob (6). NOTE Pull front panel away from chassis slightly to gain access to rear.
TM 11-5820-670-30 2-54. SQ DIS SWITCH S9602 AND XMTR TEST SWITCH S9603 REPLACEMENT. (CONT) INSTALLATION 1. 2. Position switch (10) in front panel (11) and install nut (9). Using socket wrench, tighten nut (9). CAUTION When performing steps 3 and 4, use extreme care to prevent damaging switches. Due to close proximity of switch terminals, use extreme care not to flow solder across switch terminals. NOTE For XMTR TEST switch, do step 3. Note wire color of item 7. For SQ DIS switch, do step 4.
TM 11-5820-670-30 2-55. TEST SWITCH S9601 REPLACEMENT. MATERIALS/PARTS: Switch, rotary, S9601 (P/N SMC619495-1) PRELIMINARY PROCEDURE: Remove A8700 assembly (para 2-45). EL1AT048 REMOVAL 1. Using screwdriver, remove two screws (1). 2. Using screwdriver and wrench, remove two screws (2), flat washers (3), and nuts (4). 3. Using hex wrench, loosen setscrew (5) and remove TEST SWITCH knob (6).
TM 11-5820-670-30 2-55. TEST SWITCH S9801 REPLACEMENT. (CONT) NOTE Place chassis in upright position. Pull front panel away from chassis slightly and move out of way. 4. Loosen captive screw (7) on A3000 assembly (8). 5. Remove hinge pin (9) and lower A3000 assembly (8) from hinge (10). 6. Using wrench, remove nut (11) and lockwasher (12). 7. Push rubber grommet (13) out of hole and bend hinge (10) slightly downward to allow removal of switch (14) from mount (15). 8.
TM 11-5820-670-30 2-56. SQ ADJ SWITCH R9602 REPLACEMENT. MATERIALS/PARTS: Switch, rotary, R9602 (P/N SMC619495-2) PRELIMINARY PROCEDURE: Remove A8700 assembly (para 2-45). REMOVAL 1. Using screwdriver, remove two screws (1). 2. Using screwdriver and wrench, remove two screws (2), flat washers (3), and nuts (4). 3. Using hex wrench, loosen setscrew (5) and remove TEST SWITCH knob (6). NOTE Place chassis in upright position. Pull front panel away from chassis slightly and move out of way. 4.
TM 11-5820-670-30 2-57. XMTR HI-LO SWITCH S9604 REPLACEMENT. MATERIALS/PARTS: Resistor, variable, S9604 (P/N RV6NAYSL253A) PRELIMINARY PROCEDURE: Remove A8700 assembly (para 2-45). REMOVAL 1. Using screwdriver, remove two screws (1). 2. Using screwdriver and wrench, remove two screws (2), flat washers (3), and nuts (4). 3. Using hex wrench, loosen setscrew (5) and remove TEST SWITCH knob (6). NOTE Place chassis in upright position. Pull front panel away from chassis slightly and move out of way. 4.
TM 11-5820-670-30 2-58. A6500 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Amplifier, radio frequency, A6500 (P/N SME619596) PRELIMINARY PROCEDURE: Remove case (para 2-39).
TM 11-5820-670-30 2-58. A6500 ASSEMBLY REPLACEMENT. (CONT) REMOVAL 1. 2. 3. 4. Using screwdriver, loosen two captive screws (1) and lower A4500 assembly (2). Disconnect white wire (P6502) (3) from J6502. Disconnect gray wire (P6001) (4) from J6001. Using screwdriver, loosen two captive screws (5) and unplug connector P6503 (6) from J6503 (7). 5. Using screwdriver, remove screw (8) from chassis. 6. Using screwdriver, remove three shouldered screws (9) and swing out A9500 assembly (10). 7.
TM 11-5820-670-30 RADIO INTERFERENCE FILTER FL9601 REPLACEMENT. MATERIALS/PARTS: Filter, radio interference, FL9601 (P/N SMD619508) PRELIMINARY PROCEDURE: Remove case (para 2-39). TOOLS: Electrical Contact Extractor, TL-711A/ARM-79 EL1AT053 REMOVAL 1. Using screwdriver, remove four screws (1) and Iockwashers (2). NOTE To gain access to rear of filter, A3000 assembly must first be raised.
TM 11-5820-670-30 2-59. RADIO INTERFERENCE FILTER FL9601 REPLACEMENT. (CONT) 2. Using screwdriver, loosen one captive screw (3) and raise A3000 assembly (4). 3. Using screwdriver, remove screw (5) and ground strap (6). 4. Raise filter (7) and, using electrical contact extractor, remove brown rf cable (8), violet rf cable (9), and orange rf cable (10) from filter (7). 5. Remove filter (7). INSTALLATION 1. 2. 3. 4. 5. 6. Connect orange rf cable (10), violet rf cable (9), and brown rf cable (8).
TM 11-5820-670-30 2-60. TRANSISTOR Q9601 REPLACEMENT. MATERIALS/PARTS: Transistor, Q9601 (P/N JAN 2N1479) Compound, heat sink, Dow Corning, DC-340 (item 1, appendix B) PRELIMINARY PROCEDURE: Remove A8700 assembly (para 2-45). REMOVAL 1. Using soldering iron, unsolder yellow wire (1) from pin (2) and jumper wire (3) from pin (4). 2. Using socket wrench and screwdriver, remove nut (5), bushing (6), wire lug (7), and screw (8). NOTE Use care when performing next step so as not to push screw from hole. 3.
TM 11-5820-670-30 2-60. TRANSISTOR Q9601 REPLACEMENT. (CONT) NOTE Due to inaccessible location of screw, it is advised that it not be removed. 4. Remove transistor (12) and insulator (13). INSTALLATION 1. Coat both sides of insulator (13) with heat sink compound. NOTE Be careful not to push screw from hole. 2. While holding screw (11) against mount, position insulator (13) and transistor (12) on mount alining pins on transistor with holes in mount. 3. Install wire lug (10) and nut (9). 4.
TM 11-5820-670-30 2-61. A4900 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Attenuator, variable, A4900 (P/N SME619695) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, loosen two captive screws (1) and swing out A4000 assembly (2). 2. Disconnect blue wire (P4902) (3) from J4902 (4). 3. Using screwdriver, loosen two captive screws (5) and move A4900 assembly (6) away from chassis. 4. Disconnect blue wire (P4901) (7) from J4901 (8). 5. Disconnect three color-coded wire plugs (9). 6.
TM 11-5820-670-30 2-62. RF ATTENUATOR AND DIODE SWITCH 24501 REPLACEMENT. MATERIALS/PARTS: Attenuator and switch assembly, Z4501 (P/N SMD619719) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Disconnect violet wire (P4503) (1) from J4503 (2) and brown wire (3) from J4502 (4). 2. Using screwdriver, loosen two captive screws (5). 3. Pull Z4501 assembly (6) straight out to remove. INSTALLATION 1. Position pins on Z4501 assembly (6) on board and push into place. 2.
TM 11-5820-670-30 2-63. REFLECTOMETER AND SIDETONE DETECTOR 24502 REPLACEMENT. MATERIALS/PARTS: Control assembly, Z4502 (P/N SMD619733) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Disconnect orange wire (P4505) (1) from J4505 (2). 2. Using screwdriver, loosen two captive screws (3). 3. Pull Z4502 assembly (4) straight out to remove. INSTALLATION 1. Position pins on Z4502 assembly (4) on board and push into place. 2. Using screwdriver, tighten two captive screws (3). 3.
TM 11-5820-670-30 2-64. LOW-PASS FILTER FL4501 REPLACEMENT. MATERIALS/PARTS: Filter, low-pass, FL4501 (P/N SMD619747) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, loosen two captive screws (1). 2. Pull FL4501 assembly (2) straight out to remove. INSTALLATION 1. Position FL4501 assembly (2) on four jacks (3) and push into place. 2. Using screwdriver, tighten two captive screws (1). FOLLOW-ON MAINTENANCE: Install case (para 2-39).
TM 11-5820-670-30 2-65. RELAYS K4501 THROUGH K4504 REPLACEMENT. MATERIALS/PARTS: Relay, armature, K4501 (P/N SMD6201 14) Relay, armature, K4502 (P/N SMD6201 16) Relay, armature, K4503 (P/N SMD6201 18) Relay, armature, K4504 (P/N SMD620120) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL NOTE For removal of relays K4501 or K4503, first remove rf attenuator and diode switch Z4501 (para 2-62).
TM 11-5820-670-30 2-66. RELAYS K9601 THROUGH K9606 REPLACEMENT. MAERIALS PARTS: Relay, armature, K9601 through K9605 (P/N SMC41433) Relay, dummy, K9606 (P/N SMC620064) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL NOTE Steps given are typical for all relays. 1. Using screwdriver, loosen two captive screws (1). 2. Pull relay (2) from socket (3). INSTALLATION 1. Position relay (2) in socket (3) and push into place. 2. Using screwdriver, tighten two captive screws (11).
TM 11-5820-670-30 2-67. A1000, A2000, A6000, AND A9700 ASSEMBLY REPLACEMENT. PRELIMINARY PROCEDURE: Remove Remove Remove Remove Remove Remove Remove A4000 A4500 A4800 A5500 A6500 A8700 A9500 assembly assembly assembly assembly assembly assembly assembly (para (para (para (para (para (para (para 2-41). 2-49). 2-40). 2-44). 2-58). 2-45). 2-42). REMOVAL 1. Disconnect orange color-coded wire plug (1) and black color-coded wire plug (2) from A6000 assembly (3). 2.
TM 11-5820-670-30 2-67. A1000, A2000, A6000, AND A9700 ASSEMBLY REPLACEMENT. (CONT) Using screwdriver, loosen one captive screw (15) and swing open A3000 assembly (16). Disconnect red wire (P2003) (17) from J2003 (18) on A2000 assembly (19). Disconnect blue wire (P1005) (20) from J1005 (21) and yellow wire (P1002) (22) from J1002 (23) on A1000 assembly (24). 10. Disconnect seven color-coded wire plugs from A1000 assembly (24) as shown in table below. 7. 8. 9. TERMINAL NO.
TM 11-5820-670-30 A1000, A2000, A6000, AND A9700 ASSEMBLY REPLACEMENT. (CONT) REMOVAL (CONT) 13. Disconnect brown wire (P6002) (1) from J6002 (2) and yellow wire (P6003) (3) from J6003 (4) on A6000 assembly (5). 14. Disconnect violet wire (P1003) (6) from J1003 (7) and green wire (P1004) (8) from J1004 (9) on A1000 assembly (10).
TM 11-5820-670-30 2-67. A1000, A2000, A6000, AND A9700 ASSEMBLY REPLACEMENT. (CONT) 15. Using screwdriver, loosen two screws (11) on wire clips (12) and remove brown wire (P6002) 16. Using screwdriver, remove one screw (13), one screw (14), and Iockwasher (15). 17. Using screwdriver, remove two screws (16) and bracket (17). 18. Using screwdriver, remove two screws (18). 19. Using screwdriver, remove three screws (19) and Iockwashers (20). 20. Remove A1000 assembly bracket (21). 21.
TM 11-5820-670-30 2-67. A1000, A2000, A6000, AND A9700 ASSEMBLY REPLACEMENT. (CONT) INSTALLATION (CONT) 10. 11. 12. 13. 14. 15. 16. Install four screws (1) and ground strap (2). Using screwdriver, tighten four screws (1). Position ground strap (3) under screw (4). Using screwdriver, tighten screw (4). Connect yellow wire (P1002) (5) to J1002 (6) and blue wire (P1005) (7) to J 1005 (8) on A1000 assembly (9). Connect red wire (P2003) (10) to J2003 (11) on A2000 assembly (12).
TM 11-5820-670-30 2-67. A1000, A2000, A6000, AND A9700 ASSEMBLY REPLACEMENT. (CONT) 19. Install two screws (22) and ground strap (23). 20. Install three screws (24). 21. Using screwdriver, tighten screws (22 and 24). 22. Plug connector P9701 (25) into J9701 (26). 23. Using screwdriver, tighten two captive screws (27). 24. Connect orange wire (P2001) (28) to J2001 (29) and black wire (P2002) (30) to J2002 (31). 25. Connect wires (28 and 30) to wire clip on A2000 assembly (32). 26.
TM 11-5820-670-30 2-68. A1000 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Tuner assembly, vhf, A1000 (P/N SMD416345) PRELIMINARY PROCEDURE: Remove A1000, A2000, A6000, and A9700 assembly (para 2-67).
TM 11-5820-670-30 2-68. A1000 ASSEMBLY REPLACEMENT. (CONT) REMOVAL 1. Using wrench, loosen three captive nuts (1). 2. Remove A1000 assembly (2). INSTALLATION 1. Turn dial (3) counterclockwise to position .00 setting as shown in view A. 2. Turn coupler (4) counterclockwise to stop (5) (view B). 3. Turn coupler (4) clockwise to position shown in view C. 4. Check pointer (6) on assembly which indicates band position of gearbox (7) (view D). 5.
TM 11-5820-670-30 2-69. A6000 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Oscillator buffer assembly, A6000 (P/N SMC619909) PRELIMINARY PROCEDURE: Remove A1000, A2000, A6000, and A9700 assembly (para 2-67).
TM 11-5820-670-30 2-69. A6000 ASSEMBLY REPLACEMENT. (CONT) REMOVAL 1. Using wrench, loosen three captive nuts (1). 2. Remove A6000 assembly (2). INSTALLATION 1. Turn dial (3) counterclockwise to position .00 setting as shown in view A. 2. Turn coupler (4) counterclockwise to stop (5) (view B). 3. Turn coupler (4) clockwise to position shown in view C. 4. Check pointer (6) on assembly which indicates band position of gearbox (7) (view D). 5.
TM 11-5820-670-30 2-70. A2000 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Oscillator, radio frequency, A2000 (P/N SMD414430) PRELIMINARY PROCEDURE: Remove A1000, A2000, A6000, and A9700 assembly (para 2-67). REMOVAL Using screwdriver, loosen two captive screws (1) and remove A2000 assembly (2). INSTALLATION 1. Turn dial (3) counterclockwise to .00 setting as shown in detailed view. 2. Aline coupler (4) with scribe mark (5). 3.
TM 11-5820-670-30 2-71. A9700 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Gearbox, A9700 (P/N SME619807) PRELIMINARY PROCEDURE: Remove A1000, A2000, A6000, and A9700 assembly (para 2-67). REMOVAL NOTE Gearbox A9700 is the end product when assemblies A1000, A2000, and A6000 are removed. See appropriate paragraphs for the removal of these assemblies. INSTALLATION NOTE Install assemblies A1000, A2000, and A6000 to gearbox A9700. See appropriate paragraphs for the installation of these assemblies.
TM 11-5820-670-30 2-72. RELAY K3001 REPLACEMENT. MATERIALS/PARTS: Relay, K3001 (P/N SMD413526) PRELIMINARY PROCEDURE: Remove case (para 2-39). REMOVAL 1. Using screwdriver, loosen captive screw (1). 2. Remove retaining plate (2). 3. Pull relay (3) straight up from socket (4). INSTALLATION 1. Position relay (3) in socket (4) and push into place. 2. Position retaining plate (2) under captive screw (1). 3. Using screwdriver, tighten captive screw (1). FOLLOW-ON MAINTENANCE: Install case (para 2-39).
TM 11-5820-670-30 2-73. A1600 ASSEMBLY REPLACEMENT. MATERIALS/PARTS: Power supply assembly, A1600 (P/N SMC416316) PRELIMINARY PROCEDURE: Remove A6500 assembly (para 2-58). REMOVAL NOTE A1600 assembly is located on top of A1000 assembly. 1. 2. 3. Disconnect three color-coded wire plugs (1). Unfasten retaining clip (2) by moving clip to right. Lift front of assembly (3) and pull forward to remove from bracket (4). INSTALLATION 1. Place assembly (3) in bracket (4) and push into place. 2.
TM 11-5820-670-30 2-74. FRONT PANEL KNOBS REPLACEMENT. MATERIALS/PARTS: Knob, frequency selector (P/N SMB620191) Knob, squelch mode and mode control (P/N SMC620189) Knob, volume control (P/N FNA1836-126-440) REMOVAL Step given is typical for the removal of all knobs. Using hex wrench, loosen two setscrews and remove knob.
TM 11-5820-670-30 2-74. FRONT PANEL KNOBS REPLACEMENT. (CONT) INSTALLATION For frequency selector knobs, do steps 1 and 2. For volume control knobs, do step 3. For squelch mode and mode control knobs, do steps 4 and 5. 1. Position knob (1) on switch shaft (2) and aline one of two setscrews (3) with flat (4) on switch shaft as shown in detailed view. 2. Using hex wrench, tighten two setscrews (3). 3. Position knob (5) on switch shaft (6) and, using hex wrench, tighten two setscrews (7). 4.
TM 11-5820-670-30 2-75. FRONT PANEL DIAL MASK REPLACEMENT. MATERIALS/PARTS: Mask, dial (P/N SMC620195) PRELIMINARY PROCEDURE: Remove frequency selector knobs (para 2-74). REMOVAL Using screwdriver, remove six screws (1) and remove dial mask (2). NOTE Some control units may use a masking plate (3) to cover the squelch switch TONE display. Remove if used. INSTALLATION NOTE Some control units may use a masking plate (3) to cover the squelch switch TONE display.
TM 11-5820-670-30 2-76. LIGHT PANEL REPLACEMENT. MATERIALS/PARTS: Panel, light (P/N SMD620232) PRELIMINARY PROCEDURE: Remove dial mask (para 2-75). REMOVAL 1. Remove four roll pins (1) from four frequency selector switch shafts (2) as shown in detail A. 2. Remove four shaft dials (3). 3. Using screwdriver, remove five panel mounting nuts (4) and remove light panel (5). INSTALLATION 1.
TM 11-5820-670-30 2-77. SWITCH AND WIRING ASSEMBLY REPLACEMENT. PRELIMINARY PROCEDURE: Remove light panel (para 2-76). REMOVAL 1. Using screwdriver, loosen two turn-lock fasteners (1) and remove cover (2). NOTE Some models may use two plastic insulator sheets to cover internal parts. Remove if used. 2. Using screwdriver, remove eight screws (3) from control panel (4). 3. Remove control panel (4). 4. Using wrench, remove two nuts (5) from end of switch S9102.
TM 11-5820-670-30 2-77. SWITCH AND WIRING ASSEMBLY REPLACEMENT. (CONT) 5. Using screwdriver and wrench, remove two screws (6), flat washers (7), Iockwashers (8), and nuts (9). 6. Move bracket (10) out of the way. 7. Using screwdriver, remove four screws (11) from end plate (12). 8. Using wrench, remove nut (13) and IT Iockwasher (14) from volume switch (15). 9. Using wrench, remove nut (16) and IT Iockwasher (17) from mode switch (18). 10.
TM 11-5820-670-30 2-78. SQUELCH SWITCH S9106 REPLACEMENT MATERIALS/PARTS: Switch, rotary, S9106 (P/N SMC 620158) PRELIMINARY PROCEDURE: Remove light panel (para 2-76). REMOVAL 1. Using screwdriver, loosen two turn-lock fasteners (1) and remove cover (2). 2. Using wrench, remove nut (3) and IT Iockwasher (4) and push switch (5) out of control panel (6). 3. Tag wires and unsolder from switch as shown in table below and as shown in detailed view.
TM 11-5820-670-30 2-78. SQUELCH SWITCH S9106 REPLACEMENT. (CONT) INDEX NO. WIRE COLOR 7 8 9 10 11 12 GRY JUMPER VlO WHT/YEL BLK WHT/YEL 4. Remove switch (5). INSTALLATION 1. Solder wires as shown in table above and detailed view and remove tags. NOTE When performing next step, ensure locating tab on switch is positioned in locating hole behind control panel. 2. Position switch (5) in control panel (6) and install IT Iockwasher (4) and nut (3) and, using wrench, tighten nuts (3). 3.
TM 11-5820-670-30 2-79. VOLUME CONTROL SWITCH R9103 REPLACEMENT. MATERIALS/PARTS: Resistor, fixed, composition (P/N RC07GF391J) Resistor, variable, R9103 (P/N RV6NAYSD251C) PRELIMINARY PROCEDURE: Remove light panel (para 2-76). REMOVAL 1. 2. Using screwdriver, loosen two turn-lock fasteners (1) and remove cover (2). Using wrench, remove nut (3) and IT Iockwasher (4) and push switch (5) out of control panel (6). 3.
TM 11-5820-670-30 2-79. VOLUME CONTROL SWITCH R 9103 REPLACEMENT. (CONT) NOTE Discard attached resistor along with defective switch. INSTALLATION NOTE Before attempting to install switch in control panel, a specified value resistor must be soldered between terminals as shown in detail A. Insulation must be installed on both wire leads of resistor prior to soldering (step 1). 1. Install insulation (10) on both wire leads of resistor (11) as shown in detail B. 2.
TM 11-5820-670-30 2-80. TENTHS FREQUENCY SELECTOR SWITCH S9103 AND/OR HUNDREDTHS FREQUENCY SELECTOR SWITCH S9104 REPLACEMENT. MATERIALS/PARTS: Switch, rotary, S9103 (PIN SMC 620162) Switch, rotary, S9104 (PIN SMC 620163) PRELIMINARY PROCEDURE: Remove switch and wiring assembly (para 2-77).
TM 11-5820-670-30 2-80. TENTHS FREQUENCY SELECTOR SWlTCH S9103 AND/OR HUNDREDTHS FREQUENCY SELECTOR SWITCH S9104 REPLACEMENT. (CONT) SWITCH S9104 SWITCH S9103 WIRE COLOR INDEX NO. BLU WHT/BLK/VIO JUMPER WHT WHT/BRN VlO YEL WHT/RED/VIO WHT/BLU RED WHT/RED/GRY BRN 5 6 7 8 9 10 11 12 13 14 15 16 WIRE COLOR BLK WHT VlO RED YEL BLU BRN INDEX NO. 17 18 19 20 21 22 23 REMOVAL To gain access to switch wire terminals it is recommended that both switches be removed from panel. 1.
TM 11-5820-670-30 2-81. MODE SWITCH S9105 REPLACEMENT. MATERIALS/PARTS: Diode, semiconductor, device, CR9101 (P/N JANIN645) Resistor, fixed, composition, R9101 (P/N RC07GF273J) Resistor, fixed, composition, R9102 (P/N RC07GF511J) Resistor, fixed, composition, R9104 (P/N RC07GF120J) Switch, rotary, S9105 (P/N SMC620159) PRELIMINARY PROCEDURE: Remove switch and wiring assembly (para 2-77). WIRE COLOR INDEX NO. RED RED WHT/RED WHT/RED WHT/RED RED 1 2 3 4 5 6 WIRE COLOR INDEX NO.
TM 11-5820-670-30 2-81. MODE SWITCH S9105 REPLACEMENT. (CONT) EL1AT075 REMOVAL NOTE View from rear of switch. Position switch locating tab as shown in illustrations. Tag all wires with index numbers for location and description. Discard resistors and diode along with defective switch. 1. Unsolder wires as shown in illustrations. 2. Remove switch.
TM 11-5820-670-30 2-81. MODE SWITCH S9105 REPLACEMENT. (CONT) INSTALLATION NOTE View from rear of switch. See FO-21 for complete wiring diagram. Before soldering wires to switch, three resistors and one diode must first be soldered in place. 1. Solder resistors and diode as shown in illustration above. WIRE COLOR INDEX NO.
TM 11-5820-670-30 2-81. MODE SWITCH S9105 REPLACEMENT. (CONT) WIRE COLOR WHT/RED WHT/BRN WHT/BRN YEL WHT WHT/GRY BLK WHT/YEL WHT/BLK INDEX NO. 7 8 9 10 11 12 13 14 15 WIRE COLOR INDEX NO. WHT/RED/GRY WHT/RED/BLU ORG WHT/YEL/GRY GRY GRY WHT/YEL/BRN WHT/ORG/BRN 16 17 18 19 20 21 22 23 WIRE COLOR INDEX NO. WHT/BLU/GRY WHT/ORG/YEL WHT/BLK/BRN WHT/VIO WHT/BLU/BRN WHT/YEL/VIO WHT/ORG/BLK BLK 24 25 26 27 28 29 30 31 EL1AT078 2. Solder wires as shown in illustration tables. 3. Remove all tags from wires.
M 11-5820-670-30 2-82. ELECTRICAL CONNECTOR J910I REPLACEMENT. MATERIALS/PARTS: Connector, receptacle, electrical (P/N MS3112E24-61P) PRELIMINARY PROCEDURE: Remove switch and wiring assembly (para 2-77). PIN NO. WIRE COLOR PIN NO. WIRE COLOR PIN NO.
TM 11-5820-670-30 2-82. ELECTRICAL CONNECTOR J9101 REPLACEMENT. (CONT) REMOVAL NOTE Tag all wires with connector pin letters. See table to verify wire color with connector pin letter. 1. Unsolder wires from connector. 2. Using screwdriver and wrench, remove four screws (1), Iockwashers (2), ground lug (3), and nuts (4). 3. Remove connector (5) from bracket (6). INSTALLATION 1. Position connector (5) in bracket (6) as shown in detailed view. 2.
TM 11-5820-670-30 2-83. TENS FREQUENCY SELECTOR SWITCH S910I REPLACEMENT. MATERIALS/PARTS: Switch, rotary, S9101 (P/N SMC620160) PRELIMINARY PROCEDURE: Remove switch and wiring assembly (para 2-77).
TM 11-5820-670-30 2-83. TENS FREQUENCY SELECTOR SWITCH S9101 REPLACEMENT. (CONT) NOTE View from rear of switch. Position switch locating tab as shown in illustrations. Tag all wires with index numbers for location and description. REMOVAL 1. Using screwdriver, remove two screws (1), retaining plate (2), cam stop (3), and cam stop guide (4). 2. Remove roll pin (5) from cam (6) and slide cam off switch stem (7). 3.
TM 11-5820-670-30 2-83. TENS FREQUENCY SELECTOR SWITCH S9101 REPLACEMENT.
TM 11-5820-670-30 2-83. TENS FREQUENCY SELECTOR SWITCH S9101 REPLACEMENT. (CONT) INSTALLATION 1. Position switch (1) in panel (2) with switch locating tab in line with hole in panel. NOTE View from rear of switch. Position switch locating tab as shown in illustration. See FO-21 for complete wiring diagram. 2. Starting from wafer A and using tags for reference, solder wires as shown in illustrations. 3.
TM 11-5820-670-30 2-84. UNITS FREQUENCY SELECTOR SWITCH S9102 REPLACEMENT. MATERIALS/PARTS: Switch, rotary, S9102 (P/N SMC-620161) PRELIMINARY PROCEDURE: Remove switch and wiring assembly (para 2-77).
TM 11-5820-670-30 2-84. UNITS FREQUENCY SELECTOR SWITCH S9102 REPLACEMENT. (CONT) EL1AT086 NOTE View from rear of switch. Position switch locating tab as shown in illustrations. Tag all wires with index numbers for location and description. 1. Using screwdriver, remove two screws (1), retaining plate (2), cam stop (3), and cam stop guide (4). 2. Remove roll pin (5) from cam (6) and slide cam off switch stem (7). 3.
TM 11-5820-670-30 2-84. UNITS FREQUENCY SELECTOR SWITCH S9102 REPLACEMENT. (CONT) REMOVAL (CONT) E L1AT087 View from rear of switch. Position switch locating tab as shown in illustrations. Tag all wires with index numbers for location and description. 5. Starting with wafer C, unsolder wires as shown in illustrations through wafer A. 6. Remove switch.
TM 11-5820-670-30 2-84. UNITS SELECTOR SWITCH S9102 REPLACEMENT. (CONT) INSTALLATION EL1AT088 1. Position switch stem (1) in hole in panel (2) alining switch locating tab (3) with alinement hole (4). EL1AT089 NOTE View from rear of switch. Position switch locating tab as shown in illustrations. See FO-21 for complete wiring diagram. 2. Starting from wafer A and using tags for reference, solder wires as shown in illustrations through wafer B.
TM 11-5820-670-30 2-84. UNITS FREQUENCY SELECTOR SWITCH S9102 REPLACEMENT.
TM 11-5820-670-30 2-84. UNITS FREQUENCY SELECTOR SWITCH S9102 REPLACEMENT. (CONT) NOTE View from rear of switch. Position switch locating tab as shown in illustrations. See FO-21 for complete wiring diagram. 3. Starting with wafer C using tags for reference, solder wires as shown in illustrations through wafer H. 4. Remove all tags from wires.
TM 11-5820-670-30 2-84. UNITS FREQUENCY SELECTOR SWITCH S9102 REPLACEMENT. (CONT) INSTALLATION (CONT) EL1AT139 5. Position switch locating tab in hole in panel (1) and install IT Iockwasher (2) and nut (3) and, using wrench, tighten nut (3). 6. Position cam (4) on switch stem (5) as shown in illustration and install roll pin (6). 7. Position cam stop guide (7) with larger area of guide toward top and install cam stop (8), retaining plate (9), and two screws (10). 8. Using screwdriver, tighten screws (10).
TM 11-5820-670-30 APPENDIX A REFERENCES A-1. SCOPE. This appendix lists all pamphlets, technical bulletins, technical manuals, and miscellaneous publications referenced in or related to this manual. A-2. MISCELLANEOUS PUBLICATIONS. Reporting of Transportation Discrepancies in Shipments . . . . . . . . . . . . . . . . . . . . . . . . . AR 55-38 Reporting of Item and Packaging Discrepancies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 A-4. TECHNICAL MANUALS. (CONT) Organizational, Direct Support and General Support Repair Parts and Special Tools List (Including Depot Maintenance Repair Parts and Special Tools): Voltmeters, Electronic, ME-30A/U, ME-30B/U, and ME-30C/U and ME-30E/U . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 A-4. TECHNICAL MANUALS. (CONT) Operator and Organizational Maintenance Manual (Including Repair Parts and Special Tool Lists): Generator, Signal, AN/URM-103 . . . . . . . . . . . . . . . . . . . . . . . . . Operator’s, Organizational, Direct Support, and General Support Maintenance Repair Parts and Special Tools List (Including Depot Maintenance Repair Parts and Special Tools List) for Multimeter AN/USM-223 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 APPENDIX B EXPENDABLESUPPLIES AND MATERIALS LIST B-1. SCOPE. This appendix lists expendable supplies and materials you will need to maintain the AN/ARC-131. B-2. EXPLANATION OF COLUMNS. a. Column 1, Item Number. This number is assigned to the entry in the listing and is referenced in the narrative instructions to identify the material. b. Column 2, Level. This column identifies the lowest level of maintenance that requires the listed item.
TM 11-5820-670-30 INDEX Subject Page A Administrative storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Alinement and adjustment procedures Audio level adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carrier squelch adjustment . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Page Subject C (CONT) Control, radio set C-7088/ARC-131 functioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-63 Control unit troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-114 Crs balanced mixer A3200 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Page Subject D (CONT) Modules and assembly replacement, A8700 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Module replacement, A1100 through A1500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Module replacement, A6300 and A6400 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Page Subject H Homer-detector amplifier assembly A4800 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Homing adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Homing flag indication troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Subject Page M (CONT) Modulator module A8100, 11.5 MHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Module replacement, A1100 through A1500 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Module replacement, A6300 and A6400 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Page Subject P (CONT) Principles of operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Homing mode Homer-detector amplifier assembly A4800 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Homing signal flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Subject Page P (CONT) Hunt cutoff detector p/o module A4200 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hunt generator module A8400 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Isolation amplifier module A6600 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Page Subject S Safety, care, and handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Second rf amplifier module A1300 . . . . . . . .
TM 11-5820-670-30 INDEX (CONT) Subject Page T (CONT) Homing mode Homing flag indication troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Homing needle indication troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Receive mode Audio distortion troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM 11-5820-670-30 GLOSSARY Section 1 ABBREVIATIONS af afc agc am crs fm if. kHz MHz rec rf rt xmit Audio frequency Automatic frequency control Automatic gain control Amplitude modulation Crystal reference system Frequency modulation Intermediate frequency Kilohertz Megahertz Receive Radio frequency Radio-transmitter Transmit Section II DEFINITION OF UNUSUAL TERMS Attenuate. To reduce signal strength. Automatic frequency control (aft).
By Order of the Secretary of the Army: Official: JOHN A. WICKHAM JR. General, United States Army Chief of Staff DONALD J. DELANDRO Brigadier General, United States Army The Adjutant General DISTRIBUTION: To be distributed in accordance with DA Form 12-36 literature requirements for AN/ARC-131. U.S.
PIN: 058533-000
This fine document... Was brought to you by me: Liberated Manuals -- free army and government manuals Why do I do it? I am tired of sleazy CD-ROM sellers, who take publicly available information, slap “watermarks” and other junk on it, and sell it. Those masters of search engine manipulation make sure that their sites that sell free information, come up first in search engines. They did not create it... They did not even scan it...
