KTR 908

MAINTENANCE MANUAL

MKTR 908VHF COMMUNICATIONS

TRANSRECEIVER

ANUAL NUMBER 006-15667-0009REVISION 9 SEPTEMBER, 2004

The enclosed tecused solely by this prohibited.

REPRODUCTIOWITHOUT THE EEXCEPT TO THERECIPIENTS EQTECHNICAL PUB105th STREET OWARNINGhnical data is eligible for export under License Designation NLR and is to be e individual/organization to whom it is addressed. Diversion contrary to U.S. law

COPYRIGHT NOTICE

1985-1994, 2004 Honeywell International Inc.

N OF THIS PUBLICATION OR ANY PORTION THEREOF BY ANY MEANS XPRESS WRITTEN PERMISSION OF HONEYWELL IS PROHIBITED, EXTENT REQUIRED FOR INSTALLATION OR MAINTENANCE OF THE UIPMENT. FOR FURTHER INFORMATION CONTACT THE MANAGER, LICATIONS, HONEYWELL, ONE TECHNOLOGY CENTER, 23500 WEST LATHE KS 66061 TELEPHONE: (913) 712-0400.

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REVISION HISTORY

KTR 908 Maintenance Manual

Part Number: 006-15667-XXXX

For each revision, add, delete, or replace as indicated.

Revision 9, Sept/2004

Revision 9 creates a new stand-alone manual for the KTR 908 which was extracted from revision 8 of the KTR 908/KFS 598/KFS 598A maintenance manual (P/N 006-05197-0008). Any revisions to the KTR 908 mKFS 598/KFS 59

The Illustrated Paschematics. Pre

ITEM ACTION

Full Reprint Replaces all previous revisions./2004 15667M09.JA Page RH-1

aintenance manual, beginning with revision 9, will not be a part of the KTR 908/8A maintenance manual.

rts List has been updated to reflect current parts lists, assembly drawings, and vious revision information has been retained for historical reference.

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THIS PAGE IS RESERVED

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TABLE OF CONTENTS

ITEM PAGE

SECTION IVTHEORY OF OPERATION

4.1 GENERAL...................................................................................................................... 4-1

4.2 GENERAL CIRCUIT THEORY...................................................................................... 4-1

4.3 DETAILED CIRCUIT THEORY...................................................................................... 4-2

4.3.1 ANTENNA INPUT CIRCUIT........................................................................................... 4-2

4.3.2 RF AMPLIFIER .............................................................................................................. 4-2

4.3.3 MIXER............................................................................................................................ 4-3

4.3.4 FIRST IF

4.3.5 SECOND

4.3.6 DETECTO

4.3.7 IF AGC C

4.3.8 RF AGC C

4.3.9 NOISE AN

4.3.10 AUDIO LO

4.3.11 AUDIO C

4.3.12 VOLUME

4.3.13 AUDIO A

4.3.14 COMMUN

4.3.15 STABILIZ

4.3.16 TRANSM

4.3.17 MODULA

4.3.18 KEYLINE

4.3.19 POWER S

5.1 GENERA

5.2 TEST AN

5.2.1 TEST EQ

5.2.2 CONDITI

5.2.3 FINAL DA

5.2.4 COMM R

5.2.5 TRANSM

5.2.6 ALIGNME/2004 15667M09.JA Page TC-1

AMPLIFIER..................................................................................................... 4-3

IF AMPLIFIER................................................................................................ 4-3

R ................................................................................................................... 4-3

IRCUIT............................................................................................................ 4-3

IRCUIT .......................................................................................................... 4-3

D CARRIER SQUELCH CIRCUIT ................................................................ 4-3

W PASS........................................................................................................ 4-4

OMPRESSOR................................................................................................. 4-4

CONTROL ..................................................................................................... 4-4

MPLIFIER........................................................................................................ 4-4

ICATION LSI SYNTHESIZER ....................................................................... 4-4

ED MASTER OSCILLATOR........................................................................... 4-5

ITTER.............................................................................................................. 4-5

TOR ................................................................................................................ 4-6

BUFFERS AND SWITCHES.......................................................................... 4-6

UPPLY .......................................................................................................... 4-6

SECTION VMAINTENANCE

L INFORMATION ........................................................................................... 5-1

D ALIGNMENT PROCEDURES .................................................................... 5-1

UIPMENT REQUIRED.................................................................................... 5-1

ONS FOR TESTING ....................................................................................... 5-4

TA TEST SHEET ........................................................................................... 5-4

ECEIVER ........................................................................................................ 5-5

ITTER.............................................................................................................. 5-6

NT .................................................................................................................. 5-8

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5.3 OVERHAUL................................................................................................................. 5-15

5.3.1 VISUAL INSPECTION ................................................................................................. 5-15

5.3.2 CLEANING................................................................................................................... 5-16

5.3.3 REPAIR........................................................................................................................ 5-21

5.3.4 DISASSEMBLY............................................................................................................ 5-26

5.3.5 ASSEMBLY.................................................................................................................. 5-26

5.4 TROUBLESHOOTING................................................................................................. 5-27

5.4.1 POWER SUPPLY TROUBLESHOOTING ................................................................... 5-27

5.4.2 SYNTHESIZER FREQUENCY COMM ........................................................................ 5-27

5.4.3 TUNING VCO VOLTAGE............................................................................................. 5-27

5.4.4 COMM LO

5.4.5 DETECTO

5.4.6 AGC AMP

5.4.7 SQUELC

5.4.8 AUDIO....

5.4.9 TRANSM

6.1 GENERA

6.2 REVISION

6.3 LIST OF

6.4 SAMPLE

6.5 KTR 908

6.6 KTR 908

6.7 KTR 908

6.8 KTR 908

6.9 KTR 908

6.10 KTR 908

6.11 KTR 908

6.12 KTR 908 /2004 15667M09.JA Page TC-2

CAL OSCILLATOR ..................................................................................... 5-28

R ................................................................................................................. 5-28

LIFIER ......................................................................................................... 5-28

H GATE......................................................................................................... 5-28

...................................................................................................................... 5-28

ITTER............................................................................................................ 5-28

SECTION VIILLUSTRATED PARTS LIST

L...................................................................................................................... 6-1

SERVICE ..................................................................................................... 6-1

ABBREVIATIONS........................................................................................... 6-1

PARTS LIST .................................................................................................. 6-3

FINAL ASSEMBLY ........................................................................................ 6-5

MAIN ASSEMBLY....................................................................................... 6-29

RECEIVER ASSEMBLY ........................................................................... 6-137

TRANSMITTER ASSEMBLY.................................................................... 6-219

ICAO FILTER ASSEMBLY ....................................................................... 6-239

RF AMP ASSEMBLY................................................................................ 6-253

AGC AMP ADAPTER ASSEMBLY .......................................................... 6-259

AUDIO BOARD ASSEMBLY.................................................................... 6-265

CONFIGURATION APPENDIX

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FIGURE 4-1 KTR 908 BLOCK DIAGRAM ........................................................................ 4-8FIGURE 4-2 KTR 908 RECEIVER BLOCK DIAGRAM..................................................... 4-9FIGURE 4-3 KTR 908 TRANSMITTER BLOCK DIAGRAM............................................ 4-10FIGURE 4-4 POWER SUPPLY BLOCK DIAGRAM........................................................ 4-11FIGURE 5-1 TYPICAL TEST SET UP .............................................................................. 5-2FIGURE 5-2 BENCH TEST............................................................................................... 5-3FIGURE 5-3 COMPUTATION OF PERCENT (%) MODULATION ................................. 5-11FIGURE 5-4 40dB R.F. ATTENUATOR.......................................................................... 5-12FIGURE 5-5 LINEAR DETECTOR.................................................................................. 5-12FIGURE 5-6 AUDIO INJECTIONS CIRCUIT .................................................................. 5-12FIGURE 5-7 ELLIPTIC FILTER TUNING INJECTION CIRCUIT .................................... 5-13FIGURE 5-8 TRANSMITTER TROUBLESHOOTING FLOWCHART............................. 5-28FIGURE 5-9 POWER SUPPLY TROUBLESHOOTING FLOWCHART.......................... 5-29FIGURE 5-10FIGURE 6-1FIGURE 6-2FIGURE 6-3FIGURE 6-4FIGURE 6-5FIGURE 6-6FIGURE 6-7FIGURE 6-8FIGURE 6-9FIGURE 6-10FIGURE 6-11FIGURE 6-12FIGURE 6-13FIGURE 6-14FIGURE 6-15FIGURE 6-16FIGURE 6-17FIGURE 6-18FIGURE 6-19FIGURE 6-20FIGURE 6-21FIGURE 6-22FIGURE 6-23FIGURE 6-24FIGURE 6-25FIGURE 6-26FIGURE 6-27FIGURE 6-28FIGURE 6-29FIGURE 6-30FIGURE 6-31FIGURE 6-32FIGURE 6-33FIGURE APP-1/2004 15667M09.JA Page TC-3

COMM RECEIVER TROUBLESHOOTING FLOWCHART........................ 5-31SAMPLE PARTS LIST ................................................................................. 6-3KTR 908 END ITEM ASSEMBLY DRAWING ............................................ 6-17KTR 908 MAIN ASSEMBLY DRAWING -0000 .......................................... 6-59KTR 908 MAIN ASSEMBLY DRAWING -0010 .......................................... 6-65KTR 908 MAIN ASSEMBLY DRAWING -0011 .......................................... 6-69KTR 908 MAIN ASSEMBLY DRAWING -0020 .......................................... 6-73KTR 908 MAIN ASSEMBLY DRAWING -0030 .......................................... 6-77KTR 908 MAIN SCHEMATIC -0000........................................................... 6-81KTR 908 MAIN SCHEMATIC -0010......................................................... 6-105KTR 908 MAIN SCHEMATIC -0011......................................................... 6-117KTR 908 MAIN SCHEMATIC -0020......................................................... 6-129KTR 908 MAIN SCHEMATIC -0030......................................................... 6-133KTR 908 RECEIVER ASSEMBLY DRAWING -0000............................... 6-161KTR 908 RECEIVER ASSEMBLY DRAWING -0010............................... 6-169KTR 908 RECEIVER ASSEMBLY DRAWING -0020............................... 6-173KTR 908 RECEIVER SCHEMATIC -0000 ............................................... 6-181KTR 908 RECEIVER SCHEMATIC -0001 ............................................... 6-199KTR 908 RECEIVER SCHEMATIC -0010 ............................................... 6-211KTR 908 RECEIVER SCHEMATIC -0020 ............................................... 6-215KTR 908 TRANSMITTER ASSEMBLY DRAWING.................................. 6-225KTR 908 TRANSMITTER SCHEMATIC................................................... 6-229KTR 908 ICAO FILTER ASSEMBLY DRAWING -0000 ........................... 6-241KTR 908 ICAO FILTER ASSEMBLY DRAWING -0010 ........................... 6-243KTR 908 ICAO FILTER ASSEMBLY DRAWING -0020 ........................... 6-245KTR 908 ICAO FILTER SCHEMATIC -0000............................................ 6-247KTR 908 ICAO FILTER SCHEMATIC -0010............................................ 6-249KTR 908 ICAO FILTER SCHEMATIC -0020............................................ 6-251KTR 908 RF AMP ASSEMBLY DRAWING.............................................. 6-255KTR 908 RF AMP SCHEMATIC .............................................................. 6-257KTR 908 AGC AMP ASSEMBLY DRAWING........................................... 6-261KTR 908 AGC AMP SCHEMATIC ........................................................... 6-263KTR 908 AUDIO BOARD ASSEMBLY DRAWING .................................. 6-267KTR 908 AUDIO BOARD SCHEMATIC................................................... 6-269KTR 908 UNIT CONFIGURATIONS DRAWING.....................................APP-3

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TABLE 5-1 RECOMMENDED CLEANING AGENTS ................................................... 5-17TABLE 5-2 UNSAFE CLEANING AGENTS.................................................................. 5-18/2004 15667M09.JA Page TC-5

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SECTION IVTHEORY OF OPERATION

4.1 GENERALThe KTR 908 is a single unit, remote mounted communication transceiver. The functional capa-bilities are:

A. A single conversion VHF receiver with a four pole varactor tuned preselector, MOS-FET RF amplifier, MOS-FET active mixer , 8-pole monolithic crystal filter and integrated circuit IF amplifiers. Automatic noise squelch with carrier operated back-up is used.

B. A broadband transmitter with flange mounted power transistors is followed by a three section elliptic function type low pass filter.

C. A power supply consisting of a high efficiency switching regulator with over voltage pr

4.2 GEA. Co

ThsigseamMpoamtroobsqprintThalsLScy1.2.3.Thof

B. TrWquwaly m/2004 15667M09.JA Page 4-1

otection and current limiting.

NERAL CIRCUIT THEORYmmunication Receivere received signal passes through part of the transmitter low-pass filter where the nal is switched to the receiver by the T-R diodes. A four pole, varactor tuned pre-lector suppresses the image and spurious signals. A dual-gate MOS-FET RF plifier provides low noise gain and acts as the RF AGC gain control. An active

OS-FET mixer converts the received signal to the 11.4MHz IF to be filtered by 8 les of monolithic crystal filter. The IF signal is amplified by two integrated circuit plifier stages, each with AGC applied. The transistor detector and squelch con-l gate follows the IF amplifier. Automatic squelch control with manual disable is tained by using a carrier to noise ratio squelch with a carrier level only back-up uelch. The audio low-pass filter for "climax" environments and the audio com-essor follow the squelch circuit. The output audio is amplified to 100 milliwatts o 500 ohms by the integrated circuit amplifier.e voltage controlled oscillator receives DC control information on the line which o carries the VCO frequency to the main board for comparison in the COMM I. The control voltage is low-pass filtered and applied to the varactor for frequen- control. The output from the J-FET VCO is buffered and directed to:

The LSI on the main board for frequency comparison.The receiver for local oscillator injection.The transmit buffers.

e transmitter buffer amplifier is controlled by the PTT enable and also by the out lock logic which will disable the transmitter in case of loss of phase-lock.ansmitter/Modulatorhen the PTT is activated the VCO frequency moves 11.4MHz down to the fre-ency displayed in the "USE" window. The transmit buffers are turned on and 20 tts output is obtained. The series-regulator modulator transistor is set to normal-

provide about half of the supply voltage to the driver and final transistor with no odulation.

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Modulation will cause the modulator output to swing nearly to ground and nearly to the supply voltage. The series regulator modulator is driven by an integrated circuit amplifier following the mic audio compressor which is used to maintain a high per-centage of modulation without overmodulating. A three section elliptic function type filter follows the transmitter to suppress harmonics, while a small amount of modulator audio is fed to the audio output for sidetone.

C. Power SupplyThe 27.5VDC from the aircraft bus is fed to the main board through a fuse and hash filter, then through a transistor switch.A power transistor provides a regulated 12 volts for the modulator, transmitter and audio power amplifier. A switching regulator provides power for the remaining sec-tions.One output of the hash filter is routed to a DC reference regulator, where +5 volts regulated DC is provided. The output of the +10 volt rectifier/filter and the +5 volt regulated reference DC are applied to the error amplifier. The output of the error amfiltA lattothspfilt+1ThpliA cucush

4.3 DE

4.3.1 A

In the receive mothrough the T/R dThe desired signwhere the impedaVaractor diodes Cdesired signal is

4.3.2 R

Q302 is a dual gaprotect the gateshigh gain, low noamplifier. Gate #point provides mais decreased to nthan 50dB of AGCter./2004 15667M09.JA Page 4-2

plifier is a pulse, which is applied to the pulse width modulator through a loop er. The loop filter provides a DC level to the pulse width modulator.15KHz oscillator applies a triangular pulse to the input of the pulse width modu-or. The pulse width modulator generates pulses with pulse width corresponding a DC level existing at its inputs. The switching amplifier pulses the primary of e switching transformer causing a pulsed waveform at the secondary corre-onding to the output of the pulse width modulator. The waveform is rectified and ered at different secondary terminals to provide 185VDC, +5VDC, -26VDC and 0VDC.e output of the +10 volt rectifier and filter is further filtered by a capacitor multi-er/regulator to produce +9VDC.current limiting circuit protects the power transistor amplifier against excessive rrents. When excessive current is sensed through the switching transformer, the rrent limiter forces the pulse width modulator to generate shorter pulses. These ort pulse widths then back down the output power from the power supply.

TAILED CIRCUIT THEORY

NTENNA INPUT CIRCUIT

de, one side of R301 is switched low by PTT, thus causing Q301 to conduct iode: CR502, CR503 and CR506 which are located on the transmitter board.

al passes through the low pass filter, then through CR503, CR502 and CR506 nce is transformed by C528 and L319 to match the first pole of the preselector. R303A and CR303B tune the double tuned circuit to the desired frequency. The

coupled to Gate #1 of the RF amplifier Q302 through C309.

F AMPLIFIER

te, enhancement mode, N-channel field-effect transistor with internal diodes to against damage due to transients during handling. It provides the necessary ise figure, good cross modulation immunity and wide AGC range required in this 1 has a positive bias with respect to the source so that the quiescent operating ximum gain when Gate #2 is near the supply voltage. As the Gate #2 voltage

ear 0 volts, the FET has approximately 40dB of attenuation thus providing more range. C315 couples the signal into the double tuned interstage bandpass fil-

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Varactor diode CR303C tunes the first stage and inductor L307 provides the coupling to the sec-ond pole which is tuned by CR303D. This coupling improves the image rejection in the front end.

4.3.3 MIXER

Capacitor C323 couples the desired signal to Gate #1 of the mixer. The mixer Q303 is also a dual gate FET as is the RF amplifier. Both Gate #1 and Gate #2 are biased positive with respect to the source by the same amount. The local oscillator signal is fed into Gate #2 at approximately 1 volt peak-to-peak. The FET provides more than 20dB of isolation between Gate #1 and Gate #2. The drain is tuned to 11.4MHz by T301 which also matches the FET into the 4100 ohm impedance of the crystal filter. The desired signal is now at 11.4MHz due to L.O. being 11.4MHz above the in-coming signal.

4.3.4 FIRST IF AMPLIFIER

The crystal filter provides the desired narrow bandpass for the receiver. The signal passes through the crystal filter and is coupled through T302 to the input of I301, the IF amplifier. AGC current is applied to pin 2 and provides approximately 40dB of AGC range. Transformer T303 tunes the collectointo the second IF

4.3.5 S

I302 is the secondto drive the detecrange. Transform

4.3.6 D

Transistor Q305 tor Q304, which itive excursions ofsome models havprovides high imptering.

4.3.7 IF

AGC voltage is dplifier I303C comout the audio vardetector collectorwhich decreasesage.

4.3.8 R

Delayed forward at which the RF Ameasured on J90age decreases, t

4.3.9 N

Transistor Q317 that impulse spikeput is lightly coupTransistor Q318 the base of trans/2004 15667M09.JA Page 4-3

r circuit to 11.4MHz and provides the impedance stepdown required to match amplifier.

ECOND IF AMPLIFIER

IF amplifier. It provides the necessary gain, AGC and output capability required tor. Reverse AGC is applied to pin 2 through R331 and provides up to 40dB of er T304 tunes the collector to 11.4MHz and matches to the detector.

ETECTOR

is the amplitude modulation detector. It is biased near collector cutoff by transis-s diode connected to provide stable bias and temperature compensation. Posi- signal turn Q305 on, negative excursions turn Q305 off creating detector action. e detector output provided for SELCAL use at pins 11, and 12 of J9081. T104 edance balanced audio that does not go through the squelch gate or audio fil-

AGC CIRCUIT

erived from the average value of the detector collector voltage. Operational am-pares this voltage with the DC reference from R383 and R384, amplifies it, filters iations, inverts it and feeds it back to the 1st and 2nd IF amplifiers. Thus, as the voltage decreases (with an increase in signal level), the AGC voltage increases the gain in the IF amplifier. J9081 pin 17 is provided for easy access to this volt-

F AGC CIRCUIT

RF AGC is provided for the RF amplifier by I303D and Q315. The RF input level GC begins to take effect is set by resistor R389. The RF AGC voltage can be 81 pin 18. As the IF AGC voltage exceeds the set reference, the RF AGC volt-

hus decreasing the gain in the RF amplifier.

OISE AND CARRIER SQUELCH CIRCUIT

amplifies the noise from the collector of the detector and limits its amplitude so s (such as ignition noise) will not be higher amplitude than other noise. The out-led to the tuned circuit L314 and C356 which is tuned to approximately 8KHz. detects the noise at 8KHz, that is passed by the filter, amplifies it and feeds it to istor Q320.

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Resistor R373 is set so that the detected noise causes the base voltage at Q320 to be low and its collector voltage to be high. Therefore, Q307 is "on" and no emitter current is supplied to the squelch gate of Q306 and no audio signal is allowed to pass (squelch closed).When a signal above squelch threshold is received, the noise output from the detector decreases, thus less noise is being fed to the noise detector Q318. Its collector is allowed to rise until tran-sistor Q320 conducts, decreasing the base voltage of Q307, thus supplying emitter current for the squelch gate Q306 and allowing the received audio to pass (squelch open).Switch S101A on the KFS 598 Control Head is coupled to the volume control shaft to allow the operator to open the squelch gate manually. When the shaft is pulled out, switch S101A closes, shorting the base of the noise detector Q318 towards ground, causing the collector to rise toward the 9 volt supply, which turns on Q320, as described above, which opens the squelch gate to allow the audio signal to pass. Carrier operated or back-up squelch operation is available when the re-ceived signal has a great deal of noise on the carrier, thus the noise detector keeps the squelch gate closed. As the carrier level increases to exceed the reference set by R389, "Carr Sq Adj" and the RF AGC voltage decreases, transistor Q321 turns "off" causing Q320 to turn "on". Again, as the collector of Qaudio to pass.

4.3.10 A

Inductor L309 anthat a half power 25dB down, provvironments.

4.3.11 A

The received signis then applied toferent voltage levrectified turning Qlimits the maximu

4.3.12 V

The AC signal is volume control issetting up a referon allowing emittC353 to the audioA 25K ohm fixed trol.

4.3.13 A

The audio signal voltage and impe500 ohm load su

4.3.14 C

The microprocesvides the divide rprovided by 3 codThe serial data clfrom the micropro/2004 15667M09.JA Page 4-4

320 decreases, Q307 is turned "off" and squelch gate Q306 allows the received

UDIO LOW PASS

d its associated capacitors form a low pass, elliptical filter. The design is such point occurs at 2.5KHz and a null occurs at 4KHz. The null, which is better than ides attenuation of audio heterodynes which may occur in "Climax Network" en-

UDIO COMPRESSOR

al is coupled through C345 to the input of I303A pin 2. The resulting AC signal I303B pin 6. The biasing for I303A and I303B is inputted on pins 3 and 5 at dif-els. If the resulting AC signal exceeds the compressor attack level, the signal is 308 on, reducing the signal level to the compressor. This gain reduction action m level to the volume control circuit.

OLUME CONTROL

coupled to I305D by C351. R357 and R358 bias I305D turning it on. When the in the off position, pin 4 I305B is turned off. I305C forward biases pin 2 of I305A ence voltage. When the resistance across S101A is increased I305B is turned er current to pass. The AC signal is then routed through R356, audio set, and amplifier.

resistor is used to set the audio level in the KFS 598 models with no volume con-

UDIO AMPLIFIER

is fed to pin 3 of I106. The signal is amplified and fed to transformer T102. The dance are transformed to provide a minimum of 100mW of audio power into a ch as headphones or an audio mixer.

OMMUNICATION LSI SYNTHESIZER

sor sends 19 bits of serial data to the COMM LSI, pin 7. This binary code pro-atio to the LSI. The LSI divides a reference signal frequency by the divide ratio e bits in the serial data. The resulting signal is used as a reference phase signal.ock pin 5, and the strobe pin 10, enable the COMM LSI to receive the serial data cessor in the KFS-598 at pin 7.

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The output of the VCO (Voltage Controlled Oscillator) Q309 is applied to the COMM SMO digital buffer through capacitor C378 and Q310. Q115 and Q116 are the active components of the buffer that provide signal to the LSI and provide isolation for the VCO. The LSI receives the output of the digital buffer at pin 11, divides the frequency by a divide ratio determined by the serial data bits from the microprocessor in the KFS-598. The output is a variable phase signal.The reference and variable phase signals are compared in a phase comparator internal to I102 with the difference between them resulting in "Up" or "Down" tuning pulses.

4.3.15 STABILIZED MASTER OSCILLATOR

4.3.15.1 Voltage Controlled Oscillator (V.C.O.)

The voltage controlled oscillator is a modified Hartley oscillator operating on the desired channel frequency in the transmit mode and 11.4MHz above the desired receive frequency when providing the L.O. signal in the receive mode. Q309 is the active component of V.C.O. and varactor diode CR303E provides electronic tuning of the oscillating frequency.As described in tthe COMM LSI syor "DN" signals reIn order to correccharge pump" coelliptic function filsation network toto tuning diode Cfrequency of the Vstabilize until no diodes CR303A,

4.3.16 TR

4.3.16.1

RF is coupled froboard. The first a60mA. When in Q501 is turned oTransformer T50match the base in

4.3.16.2

RF drive is fed tothe collector suppto the driver, Q50

4.3.16.3

Q504 is operatedbroadband tuned

4.3.16.4

Capacitors C534The final is operaance is stepped u/2004 15667M09.JA Page 4-5

he COMM LSI Synthesizer section, the "UP" or "DN" signals are produced from nthesizer which corresponds to the selected frequency of operation. The "UP" present the difference in frequency between the reference and variable signals. t frequency difference, the "UP" or "DN" signals are applied to a "current source nsisting of Q117, Q118 and Q119 and the output DC signal is fed to a low pass ter of L310 and C367. C366, C368, R395, R396 and C369 are a phase compen- provide loop stability. The output of the low pass filter is a DC voltage applied R303E which provides tuning of the VCO to the desired frequency. When the CO is tuned, the output of charge pump and consequently the DC tuning voltage

further change takes place. The DC tuning voltage is also applied to varactor CR303B, CR303C and CR303D for tuning of their corresponding filters.

ANSMITTER

Pre-Pre-Driver

m the buffers on the receiver board to the amplifier chain on the transmitter mplifier, Q502, is operated in Class A with a constant current of approximately

receive mode, bias transistor Q506 is turned off to remove bias from Q502 and n to short any signals to ground and prevent radiation on the L.O. frequency. 1 is broadband and is used to transform Q502 collector impedance down to put impedance of Q503.

Pre-Driver

the pre-driver, Q503 through C508 and C532. Q503 is operated Class C and ly voltage is fully modulated. The collector is broadband tuned and is coupled 4, by T502, C512 and C533.

Driver

Class C and the collector supply voltage is fully modulated. The collector is and coupled to the final by T503.

Final

and C518 form the input matching network for the final power amplifier, Q505. ted Class C and its collector is fully modulated. The low collector output imped-p to 50 ohms by transformer T504.

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4.3.16.5 Low Pass Filter

A four section elliptic function low pass filter is placed between the final and the antenna to atten-uate all harmonics which may be generated in the transmitter. During the receive mode, T/R di-odes CR502, CR503 and CR506 are forward biased to feed the desired signal from the antenna through the low pass filter to the receiver RF amplifier.

4.3.17 MODULATOR

The microphone audio enters pin 6 of J9081 and routed to the 1K ohm pot R111, which sets the mic level to the Tx-Compressor circuit consisting of Q120, I101A and I101B. The operation of this compressor is basically the same as the Rx-Compressor, see 4.3.11 AUDIO COMPRESSOR. As the output of I101B increases, it turns on Q120 harder shunting more of the mic audio to ground. R120 sets the compressor attack point. The mic audio proceeds from I101A output to the modu-lator driver I107. I107 drives transformer T103 which supplies the audio drive to the modulators Q109 and Q110. The output of the modulators supplies current to the collector of the pre-driver, driver and final in the transmitter chain. Q109 and Q110 act as a series pass regulator whose ref-erence voltage vathe receiver audi

4.3.18 K

The KTR 908 usetransmit mode. Inthe base of Q112causing the colleshunts the transmand Q312, the tw598 where it is invmicroprocessor tois just the reverseswitch (Q501) is is a low. Pin 26 gIt also causes the

4.3.19 P

4.3.19.1

The 27.5 volt aircsource of power fpower switch, Q1cated in the charFilter network L1on the 27.5V line

4.3.19.2

The 12 volt regulconnected to 27 vR149 for temperavoltage divider toto the modulator /2004 15667M09.JA Page 4-6

ries with the modulation input. Modulator output is also capactively coupled to o circuits for sidetone through C178.

EYLINE BUFFERS AND SWITCHES

s several different voltage levels to affect various changes in circuitry during the the receive mode, the cathode of CR101 is connected to an open circuit causing to go high shutting off Q113. The collector of Q112 goes low biasing Q113 off ctor to go 9 volts (RC). This signal, RC (+9V) goes to Q501 turning it on which itter drive to ground in receive mode. It also turns on Q313, which turns off Q311

o transmit buffers. The output of Q113 is high in receive which is sent to the KFS erted and translated to 5 volts and applied the microprocessor. This causes the program the COMM LSI 11.4MHz high for IF injection. In the transmit mode, it , Q112 is turned on, Q113 is turned on and RC is 0 volts. The transmit enable

turned off, the transmit buffers are turned on, and pin 26 of the microprocessor oing low causes the microprocessor to program the COMM LSI on frequency. display to exhibit at "T".

OWER SUPPLY

+27.5 Volt DC Supply

raft bus is fed to a fuse and hash filter, L126 and C121. This provides a clean or the modulator, the 12 volt regulator ,and the switching regulator. The remote 01 and Q102, is operated by low current switching in the control unit. C181 lo-ge pump driver provides additional line filtering for the switched 27 volt supply. 27, C101, C102 and C103 keep the switching regulator "HASH" from appearing .

12 Volt Regulator

ator, Q108, is a Darlington-connected power transistor, the collector of which is olts. The base is connected to a voltage divider network that includes a posistor, ture compensation. The +12 volt regulated supply on the emitter is set by this provide the desired transmitter power output by varying the DC supply voltage driver and the last transmitter buffer.

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Revision 9, Sept

The posistor (R149) is mounted on the same heatsink as Q108 and connected so that under ex-tremely high temperature operation, the +12 volt line is decreased to reduce the power dissipation in the transmitter and prevent damage to the semiconductors. R225 is used to set the 12 volts higher or lower for proper transmitter power output.

4.3.19.3 Switching Regulator

The basic concept of switching regulator is to turn "ON" and "OFF" the switching transistor Q104 so that power can be transferred from the primary of T101 to the secondary and the associated rectifiers.The +27.5 volt DC is fed to a 5 volt regulator, I104. The regulated 5 volt output of I104 is applied to the non-inverting terminal of error amplifier (comparator) I103A as a reference DC level. A 10 volt variable DC level from the output of the switching transformer is divided in half by a voltage divider network of R185 and R186. Diode CR105 limits the "+5 volt DC" output voltage to 5.7 volts DC when it is forward biased and therefore provides protection for the circuits using the "+5 volt DC" supply. Comparator I103A compares the DC reference and DC variable voltages; the output is open circuited verting terminal. terminal is less thI103C is connectof the pulse widthinverting terminalfore the output puducts, Q104 condT101. When Q10the primary stopsto the secondarypends on the pulDiode CR107 andDC level. This 10width of the pulseI103D provides cter of Q104 increaand adjusts the Dpulses passing thThe "-26 volt DC"ory. Rectifier diodby C176 and R20C176 and therefoemitter voltage dr"+9 volt DC" suppRectifier diode CRcharge display. Q/2004 15667M09.JA Page 4-7

for voltage at the inverting terminal being greater than the voltage at the non-in- The output of I103A sinks current to ground when the voltage at the inverting an the voltage at the non-inverting terminal.ed as an 18KHz oscillator producing a ramp waveform at the inverting terminal modulator, I103B. When the output of I103A is open, the voltage at the non- of I103B is set to 2.5VDC by voltage divider resistors R191 and R192 and there-lses of I103C are applied to driver (emitter follower) Q103. When Q103 con-ucts too and pulls current through the primary winding of switching regulator 3 is turned off, Q104 goes into an off state and therefore the current flow through . This change of current in T101 produces a changing flux which transfers power of T101 and associated rectifiers. The amount of delivered output power de-se width of current pulses in the primary of T101. capacitor C173 rectify and filter the output voltage of T101 and provide a 10 volt volt DC level is sensed by error amplifier I103 where its output adjusts the pulse width modulator.

urrent limit protection for switching transistor Q104. When the current in the emit-ses, I103D senses the change of voltage felt across R204 at the emitter of Q104 C level at the non-inverting terminal of I103B so that the pulse width of current rough Q104 decreases. is produced by rectifier CR109 and filter C175 and fed to the non-volatile mem-e CR107 and filter C173 produce a "+10 volt DC" voltage which is further filtered 6. Transistors Q105 and Q106 provide a capacitive multiplier for filter capacitor re improves the quality of filtering for the "+9 volt DC" supply. The collector to op of Q105 is maintained at 1 volt while Q106 provides the current drive for the ly.106 and filter capacitor C172 provide the "+185 volt DC" supply for the gas dis-310 in the control unit provides current limiting for the "+185 volt DC" supply.

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FIGURE 4-1 KTR 908 BLOCK DIAGRAM

B KTR 908


FIGURE 4-2 KTR 908 RECEIVER BLOCK DIAGRAM

B KTR 908


FIGURE 4-3 KTR 908 TRANSMITTER BLOCK DIAGRAM

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FIGURE 4-4 POWER SUPPLY BLOCK DIAGRAM

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Revision 9, Sept

SECTION VMAINTENANCE

5.1 GENERAL INFORMATIONThis section contains information on tests, alignment, inspection, cleaning, repair and trouble-shooting procedures for the KTR 908.

5.2 TEST AND ALIGNMENT PROCEDURES

5.2.1 TEST EQUIPMENT REQUIRED

The following tests equipment or equivalent is required to properly align and test the KTR 908. All test equipment must be calibrated before attempting alignment.

A. Power SupplySo

B. RFBo

C. AuHP

D. DiFl

E. RFBi

F. FrHP

G. AuEi

H. KT00wi

I. KFJ. Os

TeK. Lin

seL. 40

Se/2004 15667M09.JA Page 5-1

rensen SRL 40-6 (27.5 @ 8 amps) or equivalent Signal Generatoronton 211 or equivalentdio Signal Generator 200CD Wide Range Oscillator or equivalent

gital Multimeteruke 8000A or equivalent Wattmeter

rd Model 611 or equivalentequency Counter 5245L with 5253 Heterodyne Converter or equivalentdio Wattmeter with load

co Model 261 or equivalentR-908 test Harness Shop fabricated from Kit 050-01800-0000 and 050-01830-00 which contain the connectors or KTS 143 with appropriate cables that come th the KTS 143 test set.S 598cilloscopektronix Model 465 or equivalentear Detector

e FIGURE 5-5 LINEAR DETECTOR for detailsdB Pade FIGURE 5-4 40dB R.F. ATTENUATOR for details

B KTR 908


NOTE:AN OPTIONAL TEST SET UP CONFIGURATION ISAVAILABLE USING THE KTS 143 TEST SET. SEEFIGURE 3-26 OF THE KTS 143 MAINTENANCE/OVERHAUL MANUAL, P/N 006-05542-0000 FORADDITIONAL INFORMATION.

FIGURE 5-1 TYPICAL TEST SET UP

B KTR 908


NOTE:OPTIONAL DF OUTPUT AVAILABLE ON 064-1023-04/05/06/07 FLAVORS ONLY

FIGURE 5-2 BENCH TEST

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Revision 9, Sept

M. KTR 908 Test Harness, shop fabricated from kit P/N 050-01946-0000 which con-tain the followings:

050-01946-0000 TEST HARNESS KIT Rev. AA --------------------------------------------------------------- SYMBOL PART NUMBER FIND NO DESCRIPTION UM -0000 --------------------------------------------------------------- 030-00005-0000 CONN BNC UG 88C/ EA 1.00 030-01157-0011 SOCKET CRMP 20G EA 20.00 030-01173-0000 CONN SUB-D HSG 25S EA 1.00 030-01186-0000 CONTACT SKT CRIMP EA 4.00 030-01188-0000 PIN POLRZTN FEMALE EA 1.00 030-02351-0002 HOOD/LVR ASSY ST E EA 1.00 030-02358-0006 CONN SUB-D PC 29S EA 1.00

This test Harness is also contained in the KTS 143 Accessory Kit.

5.2.2 CONDITIONS FOR TESTING

All specifications pertain to the following input and environmental conditions unless specified oth-erwise.

A. AmB. SuC. ChD. Al

6d6d

E. Un10

F. ThG. A

illuH. AlI >

126.508 MHzBelow ______ 126.515 MHzBelow ______

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Revision 9, Sept

4. Volume Gain Control:Min__________NMT 20mVMax. ________ NLT 7.07V at 500 ohmInput a standard 100uV signal into the unit. Disable the squelch control by pulling the volume knob out and monitoring the audio output.

5. Audio Distortion:350Hz = ___(15% Max), 1KHz =___(15% Max), 2.5KHz = ___(15% Max)Input a 100uV 85% modulated signal between 350Hz and 2500Hz. (This is an op-tional test that requires a distortion analyzer).

6. Audio Response:350Hz = ________ NMT 6dB down 1KHz = 0dB 2.5KHz = ______ NMT 6dB down Input a standard 100uV signal into the unit. Disable the compressor at pin 2 J9081. M

7. CoIn

8. SqNOa.b.

c.d.

e.

5.2.5 TR

A. PoCovaSe11121315

Af111213151112/2004 15667M09.JA Page 5-6

onitor the receiver output.mpressor: _______________NMT +/- 4dB increase from 30% to 85% mod.

put a standard 100uV signal into the unit. Vary the modulation from 30% to 85%.uelch:TE: Squelch adjustments must be performed in the following order:

Set the unit at 126.50MHz.Carrier/Noise Squelch set to open at 2uV and to close at NMT 4dB below the squelch opening.Carrier/Noise Squelch __________OK.With the unit set to 126.50MHz input a 8KHz 85% modulated signal into the unit. Set the Carrier Squelch to open at 12.5uV +/- 3uVCarrier Squelch _____________OK

ANSMITTER

wer Out:nnect a wattmeter to the antenna output and record the following un-modulated lues.t A + input to ________ 27.5VDC @ Pin 8. (Loaded Value)8.00MHz _____ 20 Watts min.6.50MHz _____ 20 Watts min.5.97MHz _____ 20 Watts min.1.97MHz ** _____ 16 Watts min.

ter 5 minutes continuous key at ambient room temperature:8.00MHz _____ 10 Watts max.6.50MHz _____ 10 Watts max.5.97MHz _____ 10 Watts max.1.97MHz ** _____ 10 Watts max. 8.00MHz _____ 4 Watts min.6.5MHz _____ 4 Watts min.

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Revision 9, Sept

135.97MHz _____ 4 Watts min.151.975MHz** _____ 4 Watts

Low voltage:With a low line voltage input the following values should be observed.22 VDC for 27.5V units118.00MHz _____5 Watts min.126.50MHz _____5 Watts min.135.97MHz _____5 Watts min.151.97MHz ** _____5 Watts min.

B. Modulation Capabilities:Input a standard modulator test signal into the microphone audio. Using the linear de1.

2.

3.

4./2004 15667M09.JA Page 5-7

tector measure the Tx modulation. 118.00MHz: _____NLT 85%126.50MHz: _____NLT 85%135.97MHz: _____NLT 85%151.97MHz:** _____NLT 85%Carrier Noise Level: Modulate the carrier with 85% at 1000Hz. * Noise on the carrier with mod-ulation removed shall be reduced by: 118MHz 126.5MHz 135.95MHz *151.97MHz _____ >40dB* ______>40dB* ______>40dB* _____>40dB* Demodulated Audio Distortion. This is an optional test that requires a dis-tortion analyzer.* Harmonic Distortion350Hz 1KHz 2.5KHz_____15% * Max _____15% * Max _____15% * MaxHeadphone Sidetone:Input a 1000Hz, 85% Mod signal into the microphone audio. Monitor the headphone output. Set the volume control to midrange. Vary R212 over its full range. Output variation should be:_________.003 Volts (Max)_________ 7.07 Volts (Min.) Measured with 500 ohm load_________ Set R212 for 1.40 at end of test.

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Revision 9, Sept

5.2.6 ALIGNMENT

5.2.6.1 Initial Adjustments

5.2.6.2

a. Tur

(1)

(2)

(3)

(4)

(5)

5.2.6.3

a. Setb. Setc. Rep

5.2.6.4

a. Setb. Setc. Rep

5.2.6.5

a. Setb. Set

5.2.6.6

a. SetTP3

b. Set

R225 Full CCW (Power Set)

R212 Mid-Range (Sidetone)

R111 Mid-Range (MIC Gain)

R356 Full CW (Audio Set)

R373 Full CCW (Noise SQ)

R389 Full CW (Car SQ)

R120 Full CW (Mod Set)/2004 15667M09.JA Page 5-8

Voltage Regulator

n unit on and check for following voltages:

At C174 -- 5V +_ .25V

At C172 -- 185V +_ 7V (J9081, pin 13)

At C173 -- 10V _+ .5V (J9081, pin 10)

At C175 -- -26V +_ 1.0V (J9081, pin 9)

At E4 (C156) -- 12V +_ 1.0V

VCO Set (064-1023-00/01/04/05/08/09/12/13)

frequency selector to 118.000MHz and adjust L312 for 5.5 +/- .1VDC at TP304. frequency selector to 135.97 MHz and adjust C373 for 10 +/- .1VDC at TP304.eat steps A and B until respective voltages are within +/- .1volt of nominal.

VCO Set (064-1023-02/03/06/07/10/11/14/15) Extended Frequency Range

frequency selector to 118.00MHz and adjust L312 for 5.5 +/- .1VDC at TP304. frequency selector to 151.97 MHz and adjust C373 for 14 +/- .25VDC at TP304.eat steps A and B until respective voltages are within the tolerance specified.

VCO Set (064-1023-00 and -04, S/N 10313 and above)

frequency selector to 136.975 MHz, and adjust L312 for 9.0 0.2 Vdc at TP304. frequency selector to 118.000 MHz, and check TP304 to be > 5.0 Vdc.

VCO Set (064-1023-02 and -06, S/N 10313 and above)

frequency selector to 151.975 MHz, and adjust L312 for 15.0 0.2 Vdc at 04.

frequency selector to 118.000 MHz, and check TP304 to be > 5.0 Vdc.

B KTR 908

Revision 9, Sept

5.2.6.7 RF and IF Alignment (064-1023-00/01/04/05/08/09/12/13)

a. Set frequency selector to 126.50MHz and connect a signal generator with a 6dB pad.

b. Apply sufficient RF to obtain approximately 4.5VDC at J9081, Pin 17. Adjust the RF level to maintain this voltage throughout alignment.

c. Adjust L301 for a voltage peak while loading L303 with a 270ohm resistor.d. Adjust L303 for a voltage peak while loading L301 with a 270ohm resistor.e. Adjust L306 for a voltage peak while loading L308 with a 270ohm resistor.f. Adjust L308 for a voltage peak while loading L306 with a 270 ohm resistor.g. Adjust T301, T302, T303 and T304 for maximum voltage.

5.2.6.8 RF and IF Alignment Extended Frequency Range (Units 064-1023-02/03/06/07/10/11/14/15)

a. Setb. Sel

padc. Adjd. Adje. Adjf. Adjg. Sel

to papp

h. Adji. Adjj. Adjk. Adjl. Repm. Repn. Adj

5.2.6.9

a. Setb. Sel

6dBat p

c. Adjgro

d. Adje. Adjf. Adjg. Sel

a 6VD

h. Adj/2004 15667M09.JA Page 5-9

C305, C308, C316 and C321 to mid range.ect 118.00MHz and connect a signal generator at 118.00MHz through a 6dB . Adjust level for approximately 4.5VDC at Pin 17 of J9081.ust L301 for a voltage peak while loading L303 with 270 ohms.ust L303 for a voltage peak while loading L301 with 270 ohms.ust L306 for a peak voltage while loading L308 with 270 ohms.ust L308 for a peak voltage while loading L306 with 270 ohms.ect 151.975MHz and set signal generator to 151.975MHz with a level sufficient roduce 4.5VDC at Pin 17 of J9081. Reduce this level as required to maintain roximately 4.5 VDC.ust C305 for a peak voltage while loading L303 with 270 ohms.ust C308 for a peak voltage while loading L301 with 270 ohms.ust C316 for a peak voltage while loading L308 with 270 ohms.ust C321 for a peak voltage while loading L306 with 270 ohms.eat steps B, C, D, E and F.eat steps H, I, J, K and L.

ust T301, T302,T303 and T304 for maximum voltage.

RF and IF Alignment (064-1023-00 and -04, S/N 10313 and above)

C305, C308, C316, and C321 to midrange.ect 118.00 MHz, and connect to a signal generator set at 118.00 MHz through a pad. Adjust the signal generator output level to maintain approximately 4.5 Vdc in 17 of J9081 throughout the alignment.ust L301 for a voltage peak at pin 17 while loading L303 with a 270W resistor (to und).ust L303 for a voltage peak while loading L301 with a 270W resistor.ust L306 for a voltage peak while loading L308 with a 270W resistor.ust L308 for a voltage peak while loading L306 with a 270W resistor.ect 136.975 MHz, and connect to a signal generator set at 136.975 MHz through dB pad. Adjust the signal generator output level to maintain approximately 4.5 C at pin 17 of J9081 throughout the alignment.ust C305 for a voltage peak while loading L303 with a 270 ohm resistor.

B KTR 908

Revision 9, Sept

i. Adjust C308 for a voltage peak while loading L301 with a 270 ohm resistor.j. Adjust C316 for a voltage peak while loading L308 with a 270 ohm resistor.k. Adjust C321 for a voltage peak while loading L306 with a 270 ohm resistor.l. Repeat steps b, c, d, e, and f.m. Repeat steps g, h, i, j, k, and l.n. Adjust T301, T302, T303, and T304 for maximum voltage at pin 17.

5.2.6.10 Noise Squelch Adjust

a. Apply a 25uV hard input signal modulated 85% with 8KHz audio.b. Adjust L314 for a maximum p-p voltage with the oscilloscope connected to the base

of Q318.c. Apply a 2.0uV hard signal modulated 30% with 1KHz tone.d. Adjust R373 CW until the output audio is just visible (observe with scope).

5.2.6.11 Carrier

a. Appb. Adj

5.2.6.12 Climax

a. Appb. Moc. Setd. Adj

5.2.6.13 Modulat

a. ConLIN

b. Keyc. Setd. Un-e. App

JECf. Keyg. Adjh. Incri. Adj

OFj. Chek. Set

5.2.6.14 Frequen

a. Witb. Adj/2004 15667M09.JA Page 5-10

Squelch Adjustment

ly a 12uV hard signal modulated 85% with 8KHz audio. ust R389 until the audio output is just visible (Observe with scope).

Filter Adjustment

ly a 100uV hard input signal modulated 85% with 5KHz audio.nitor the audio output with an oscilloscope. the volume control for a convenient reading on the scope.ust L309 for a minimum output voltage (NULL).

or Adjust - Sidetone Set

nect the KTR 908 to an RF wattmeter with a linear detector (see FIGURE 5-5 EAR DETECTOR). the transmitter. power out at 126.5MHz to 20-26 watts with R225.key the transmitter.ly .4VRMS (No Load) standard MIC audio signal (see FIGURE 5-6 AUDIO IN-TIONS CIRCUIT). the transmitter.ust R111 for 90% modulation.ease MIC audio from .4 to 1.0VRMS.ust R120 for 90% modulation on 126.5MHz (see FIGURE 5-3 COMPUTATION PERCENT (%) MODULATION).ck modulation tracking across band.

R212 for 1.4V RMS sidetone with 85% modulation.

cy Adjust

hin 15 seconds after turn on, key transmitter.ust C124 to selected channel frequency within 1000Hz.

B KTR 908

Revision 9, Sept

FI/2004 15667M09.JA Page 5-11

GURE 5-3 COMPUTATION OF PERCENT (%) MODULATION

B KTR 908

Revision 9, Sept

FIGURE 5-4 40dB R.F. ATTENUATOR/2004 15667M09.JA Page 5-12

FIGURE 5-5 LINEAR DETECTOR

FIGURE 5-6 AUDIO INJECTIONS CIRCUIT

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FIGURE 5-7 ELLIPTIC FILTER TUNING INJECTION CIRCUIT/2004 15667M09.JA Page 5-13

B KTR 908



B KTR 908

Revision 9, Sept

5.3 OVERHAUL

5.3.1 VISUAL INSPECTION

This section contains instructions and information to assist in determining, by visual inspection, the condition of the units major assemblies and subassemblies. These inspection procedures will assist in finding defects resulting from wear, physical damage, deterioration, or other causes. To aid inspection, detailed procedures are arranged in alphabetical order.

A. Capacitors, FixedInspect capacitors for case damage, body damage, and cracked, broken, or charred insulation. Check for loose, broken, or corroded terminal studs, lugs, or leads. Inspect for loose, broken, or improperly soldered connections. On chip caps, be especially alert for hairline cracks in the body and broken terminations.

B. Capacitors, VariableInspect trimmers for chipped and cracked bodies, damaged dielectrics, and dam-ag

C. ChIndada

D. CiInimbu

E. CoInchbrsp

F. CoInso

G. FlInes

H. FrChtigno

I. FuIn

J. InInbu

K. JaInins/2004 15667M09.JA Page 5-15

ed contacts.assis

spect the chassis for loose or missing mounting hardware, deformation, dents, maged fasteners, or damaged connectors. In addition, check for corrosion or mage to the finish that should be repaired.rcuit Boardsspect for loose, broken, or corroded terminal connections; insufficient solder or proper bonding; fungus, mold, or other deposits; and damage such as cracks, rns, or charred traces.nnectors

spect the connector bodies for broken parts; check the insulation for cracks, and eck the contacts for damage, misalignment, corrosion, or bad plating. Check for oken, loose, or poorly soldered connections to terminals of the connectors. In-ect connector hoods and cable clamps for crimped wires.vers and Shields

spect covers and shields for punctures, deep dents, and badly worn surfaces. Al-, check for damaged fastener devices, corrosion and damage to finish.ex Circuitsspect flex circuits for punctures, and badly worn surfaces. Check for broken trac-, especially near the solder contact points.ont Paneleck that name, serial, and any plates or stickers are secure and hardware is ht. Check that the handle is functional, securely fastened, and handle casting is t damaged or bent.se

spect for blown fuse and check for loose solder joints.sulatorsspect insulators for evidence of damage, such as broken or chipped edges, rned areas, and presence of foreign matter.cksspect all jacks for corrosion, rust, deformations, loose or broken parts, cracked ulation, bad contacts, or other irregularities.

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L. PotentiometersInspect all potentiometers for evidence of damage or loose terminals, cracked in-sulation or other irregularities.

M. Resistors, FixedInspect the fixed resistors for cracked, broken, blistered, or charred bodies and loose, broken, or improperly soldered connections. On chip resistors, be especially alert for hairline cracks in the body and broken terminations.

N. RF CoilsInspect all RF coils for broken leads, loose mountings, and loose, improperly sol-dered, or broken terminal connections. Check for crushed, scratched, cut or charred windings. Inspect the windings, leads, terminals and connections for cor-rosion or physical damage. Check for physical damage to forms and tuning slug adjustment screws.

O. Terminal Connections Soldered(1

(2

(3

(4P. Tr

(1

(2

Q. WInlac

5.3.2 C

A. GeThsu/2004 15667M09.JA Page 5-16

) Inspect for cold-soldered or resin joints. These joints present a porous or dull, rough appearance. Check for strength of bond using the points of a tool.

) Examine the terminals for excess solder, protrusions from the joint, pieces adhering to adjacent insulation, and particles lodged between joints, con-ductors, or other components.

) Inspect for insufficient solder and unsoldered strands of wire protruding from the conductor at the terminal. Check for insulation that is stripped back too far from the terminal.

) Inspect for corrosion at the terminal.ansformers) Inspect for signs of excessive heating, physical damage to the case,

cracked or broken insulation, and other abnormal conditions.) Inspect for corroded, poorly soldered, or loose connecting leads or termi-

nals.iring/Coaxial Cablespect wiring in chassis for breaks in insulation, conductor breaks, cut or broken ing and improper dress in relation to adjacent wiring or chassis.

LEANING

neralis section contains information to aid in the cleaning of the component parts and bassemblies of the unit.

WARNING:GOGGLES ARE TO BE WORN WHEN USINGPRESSURIZED AIR TO BLOW DUST ANDDIRT FROM EQUIPMENT. ALL PERSONNELSHOULD BE WARNED AWAY FROM THE IM-MEDIATE AREA.

B KTR 908

Revision 9, Sept

WARNING:OPERATIONS INVOLVING THE USE OF ACLEANING SOLVENT SHOULD BE PER-FORMED UNDER A VENTILATED HOOD.AVOID BREATHING SOLVENT VAPOR ANDFUMES; AVOID CONTINUOUS CONTACTWITH THE SOLVENT. WEAR A SUITABLEMASK, GOGGLES, GLOVES, AND AN APRONWHEN NECESSARY. CHANGE CLOTHINGUPON WHICH SOLVENTS HAVE BEENSPILLED.

WARNING:

B. ReTAing

Denatured

DuPont V

PolaClearwipe TX12

KimWipes(Kimberly

Cloth, lint-

Brush, fla

Brush, rou

Dishwash/2004 15667M09.JA Page 5-17

OBSERVE ALL FIRE PRECAUTIONS FORFLAMMABLE MATERIALS. USE FLAMMABLEMATERIALS IN A HOOD PROVIDED WITHSPARK-PROOF ELECTRICAL EQUIPMENTAND AN EXHAUST FAN WITH SPARKPROOFBLADES.

commended Cleaning AgentsBLE 5-1 RECOMMENDED CLEANING AGENTS lists the recommended clean- agents to be used during overhaul of the unit.

NOTE:EQUIVALENT SUBSTITUTES MAY BE USED FORLISTED CLEANING AGENTS.

TABLE 5-1 RECOMMENDED CLEANING AGENTS

TYPE USED TO CLEAN

Alcohol Various, exterior and interior

ertrel SMT Various, interior

Cleaner (Polaroid Corp.) or Tex-9 (Texwipe Co.)

CRT display filter, LCD displays, and gen-eral purpose lens/glass cleaner.

lint-free tissue Clark Corp.)

Various

free cotton Various

t with fiber bristles Various

nd with fiber bristles Various

ing liquid (mild) Nylon, Rubber Grommets

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Revision 9, Sept

C. Recommended Cleaning Procedures

CAUTION:DO NOT ALLOW SOLVENT TO RUN INTOSLEEVES OR CONDUIT THAT COVERSWIRES CONNECTED TO INSERT TERMI-NALS.

1. Exterior(a) Wipe dust cover and front panel with a lint-free cloth dampened with

denatured alcohol.(b) For cleaning connectors, use the following procedure.

(1) Wipe dust and dirt from bodies, shells, and cable clamps us-ing a lint-free cloth moistened with denatured alcohol.

2.

FREON TF, IMC

CARBON TETRACHLO

CHLOROFORM

TRICHLOROETHYLEN

PROPYL ALCOHOL

ETHYL ALCOHOL

XYLENE/2004 15667M09.JA Page 5-18

(2) Wipe parts dry with a clean, dry lint-free cloth.(3) Remove dirt and lubricant from connector inserts, insulation,

and terminals using a small soft bristled brush moistened with denatured alcohol.

(4) Dry the inserts with an air jet.(c) Remove cover(s).(d) If necessary, open any blocked ventilation holes by first saturating

the debris clogging the apertures with denatured alcohol and then blowing the loosened material out with an air stream.

InteriorThe following solvents are no longer recommended for benchtop or rework cleaning of printed circuit boards, modules, or sub-assemblies.

TABLE 5-2 UNSAFE CLEANING AGENTS

TRICHLOROETHANE

RIDE DETERGENT (ALL AND EQUIVALENTS)METHYLENE CHLORIDE

E GENESOLV 2004/2010

METHYL ALCOHOL

BUTYL ALCOHOL

PRELETE (CFC-113)

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Revision 9, Sept

CAUTION:DO NOT USE SOLVENT TO CLEAN PARTSCOMPOSED OF OR CONTAINING NYLON ORRUBBER GROMMETS. CLEAN THESEITEMS WITH MILD LIQUID DISHWASHINGDETERGENT AND WATER. USE DETER-GENT FOR THIS PURPOSE ONLY.

CAUTION:DUPONT VERTREL SMT DOES HAVE GEN-ERAL MATERIAL COMPATIBILITY PROB-LEMS WITH POLYCARBONATE, POLYSTY-RENE, AND RUBBER. IT IS RECOMMENDEDTHAT THESE MATERIALS BE CLEANED/2004 15667M09.JA Page 5-19

WITH DENATURED ALCOHOL.

CAUTION:DO NOT ALLOW EXCESS CLEANING SOL-VENT TO ACCUMULATE IN ANY OF THE AD-JUSTMENT SCREW CREVICES AND THERE-BY SOFTEN OR DISSOLVE THE ADJUST-MENT SCREW EPOXY SEALANT.

CAUTION:AVOID AIR-BLASTING SMALL TUNING COILSAND OTHER DELICATE PARTS BY HOLDINGTHE AIR NOZZLE TOO CLOSE. USE BRUSH-ES CAREFULLY ON DELICATE PARTS.

CAUTION:IMPROPER CLEANING CAN RESULT IN SUR-FACE LEAKAGE AND CONDUCTIVE PARTIC-ULATES, SUCH AS SOLDER BALLS OR ME-TALLIC CHIPS, WHICH CAN CAUSE ELEC-TRICAL SHORTS. SEVERE IONIC CONTAM-INATION FROM HANDLING AND FROMENVIRONMENTAL CONDITIONS CAN RE-SULT IN HIGH RESISTANCE OR OPEN CIR-CUITS.

CAUTION:ULTRASONIC CLEANING CAN DAMAGECERTAIN PARTS AND SHOULD GENERALLYBE AVOIDED.

B KTR 908

Revision 9, Sept

NOTE:Solvents may be physically applied in several waysincluding agitation, spraying, brushing, and vapordegreasing. The cleaning solvents and methodsused shall have no deleterious effect on the parts,connections, and materials being used. If sensitivecomponents are being used, spray is recommended.Uniformity of solvent spray flow should be maxi-mized and wait-time between soldering and cleaningshould be minimized.

NOTE:Clean each module subassembly. Then remove anyforeign matter from the casting./2004 15667M09.JA Page 5-20

Remove each module subassembly. Then remove any foreign matter from the casting.(a) Casting covers and shields should be cleaned as follows:

(1) Remove surface grease with a lint-free cloth.(2) Blow dust from surfaces, holes, and recesses using an air

stream.(3) If necessary, use a solvent, and scrub until clean, working

over all surfaces and into all holes and recesses with a suit-able non-metallic brush.

(4) Position the part to dry so the solvent is not trapped in holes or recesses. Use an air stream to blow out any trapped sol-vent.

(5) When thoroughly clean, touch up any minor damage to the finish.

(b) Assemblies containing resistors, capacitors, rf coils, inductors, transformers, and other wired parts should be cleaned as follows:(1) Remove dust and dirt from all surfaces, including all parts

and wiring, using soft-bristled brushes in conjunction with air stream.

(2) Any dirt that cannot be removed in this way should be re-moved with a brush (not synthetic) saturated with an ap-proved solvent, such as mentioned above. Use of a clean, dry air stream (25 to 28 psi) is recommended to remove any excess solvent.

(3) Remove flux residue, metallic chips, and/or solder balls with an approved solvent.

(c) Wired chassis devices containing terminal boards, resistor and ca-pacitor assemblies, rf coils, switches, sockets, inductors, transform-ers, and other wired parts should be cleaned as follows:

B KTR 908

Revision 9, Sept

NOTE:When necessary to disturb the dress of wires andcables, note the positions before disturbing and re-store them to proper dress after cleaning.

(1) Blow dust from surfaces, holes, and recesses using an air jet.

(2) Finish cleaning chassis by wiping finished surfaces with a lint-free cloth moistened with solvent.

(3) Dry with a clean, dry, lint-free cloth.(4) When thoroughly clean, touch-up any minor damage to the

finish.(5) Protect the chassis from dust, moisture, and damage pend-

ing inspection.

5.3.3 R

A. GeThThallanrethm

B. Re/2004 15667M09.JA Page 5-21

(d) Ceramic and plastic parts should be cleaned as follows:(1) Blow dust from surfaces, holes, and recesses using an air

jet.(2) Finish cleaning chassis by wiping finished surfaces with a

lint-free cloth moistened with solvents.(3) Dry with a clean, dry, lint-free cloth.

EPAIR

neralis section contains information required to perform limited repairs on the unit. e repair or replacement of damaged parts in airborne electronic equipment usu-y involves standard service techniques. In most cases, examination of drawings d equipment reveals several approaches to perform a repair. However, certain pairs demand following an exact repair sequence to ensure proper operation of e equipment. After correcting a malfunction in any section of the unit, it is recom-ended that a repetition of the functional test of the unit be performed.pair Precautions

WARNINGTHIS UNIT CONTAINS VOLTAGES THAT AREDANGEROUS TO LIFE. REMOVE ALL POW-ER BEFORE PROCEEDING WITH REPAIR.

CAUTIONTHIS EQUIPMENT CONTAINS ELECTRO-STATIC DISCHARGE SENSITIVE (ESDS) DE-VICES. EQUIPMENT MODULES AND ESDSDEVICES MUST BE HANDLED IN ACCOR-DANCE WITH SPECIAL ESDS HANDLINGPROCEDURES.

B KTR 908

Revision 9, Sept

1. Ensure that all ESDS and MOS handling precautions are followed.2. Perform repairs and replace components with power disconnected from

equipment.3. Use a conductive table top for repairs and connect table to ground conduc-

tors of 60Hz and 400Hz power lines.4. Replace connectors, coaxial cables, shield conductors, and twisted pairs

only with identical items.5. Reference component side of a printed circuit board in this manual means

the side on which components are located; solder side refers to the other side. The standard references are as follows: nearside is the component side; farside is the solder side; on surface mount boards with components on both sides, the nearside is the side that has the J#### and P#### con-nector numbers.

6. When repairing circuits, carefully observe lead dress and component orien-

7.

8.

C. El1.

2.3.4.5.6.7.8.

9.

10/2004 15667M09.JA Page 5-22

tation. Keep leads as short as possible and observe correct repair tech-niques.There are certain soldering considerations with surface mount compo-nents. The soldering iron tip should not touch the ceramic component body. The iron should be applied only to the termination-solder filet.Observe cable routing throughout instrument assembly, prior to disassem-bly, to enable a proper reinstallation of cabling during reassembly proce-dures.

ectrostatic Sensitive Devices (ESDS) ProtectionAlways discharge static before handling devices by touching something that is grounded.Use a wrist strap grounded through a 1M resistor.Do not slide anything on the bench. Pick it up and set it down instead.Keep all parts in protective cartons until ready to insert into the board.Never touch the device leads or the circuit paths during assembly.Use a grounded tip, low wattage soldering station.Keep the humidity in the work environment as high as feasibly possible.Use grounded mats on the work station unless table tops are made of ap-proved antistatic material.Do not use synthetic carpet on the floor of the shop. If a shop is carpeted, ensure that a grounded mat is placed at each workstation.

. Keep common plastics out of the work area.

B KTR 908

Revision 9, Sept

D. MOS Device ProtectionMOS (Metal Oxide Semiconductor) devices are used in this equipment. While the attributes of MOS type devices are many, characteristics make them susceptible to damage by electrostatic or high voltage charges. Therefore, special precautions must be taken during repair procedures to prevent damaging the device. The fol-lowing precautions are recommended for MOS circuits, and are especially impor-tant in low humidity or dry conditions.1. Store and transport all MOS devices in conductive material so that all ex-

posed leads are shorted together. Do not insert MOS devices into conven-tional plastic snow or plastic trays used for storing and transporting stan-dard semiconductor devices.

2. Ground working surfaces on workbench to protect the MOS devices.3. Wear cotton gloves or a conductive wrist strap in series with a 200K re-

sistor connected to ground.4.5.

6.

7.8.

9.

10

11

12

13

14

E. PC1.

2./2004 15667M09.JA Page 5-23

Do not wear nylon clothing while handling MOS devices.Do not insert or remove MOS devices with power applied. Check all power supplies to be used for testing MOS devices. and be sure that there are no voltage transients present.When straightening MOS leads, provide ground straps for the apparatus for the device.Ground the soldering iron when soldering a device.When possible, handle all MOS devices by package or case, and not by leads. Prior to touching the device, touch an electrical ground to displace any accumulated static charge. The package and substrate may be elec-trically common. If so, an electrical discharge to the case would cause the same damage as touching the leads. Clamping or holding fixtures used during repair should be grounded, as should the circuit board, during repair.

. Devices should be inserted into the printed circuit boards such that leads on the back side do not contact any material other than the printed circuit board (in particular, do not use any plastic foam as a backing).

. Devices should be soldered as soon as possible after assembly. All solder-ing irons must be grounded.

. Boards should not be handled in the area around devices, but rather by board edges.

. Assembled boards must not be placed in conventional, home-type, plastic bags. Paper bags or antistatic bags should be used.

. Before removing devices from conductive portion of the device carrier, make certain conductive portion of carrier is brought in contact with well grounded table top.

Board, Two-Lead Component Removal (Resistors, Capacitors, Diodes, etc.)Heat one lead from component side of board until solder flows, and lift one lead from board; repeat for other lead and remove component (note orien-tation).Melt solder in each hole, and using a desoldering tool, remove solder from each hole.

B KTR 908

Revision 9, Sept

3. Dress and form leads of replacement component; insert leads into correct holes.

4. Insert replacement component observing correct orientation.

F. PC Board, Multi-Lead Component Removal (ICs, etc.)1. Remove component by clipping each lead along both sides. Clip off leads

as close to component as possible. Discard component.2. Heat hole from solder side and remove clipped lead from each hole.3. Melt solder in each hole, and using a desoldering tool, remove solder from

each hole.4. Insert replacement component observing correct orientation.5. Solder component in place from farside of board. Avoid solder runs. No sol-

der is required on contacts where no traces exist.

G. Re1.

2.

3.

4.

5.

H. Re

1.

2.

3.4.

5./2004 15667M09.JA Page 5-24

placement of Power TransistorsUnsolder leads and remove attaching hardware. Remove transistor and hard-coat insulator.Apply Thermal Joint Compound Type 120 (Wakefield Engineering, Inc.) to the mounting surface of the replacement transistor.Reinstall the transistor insulator and the power transistor using hardware removed in step (1).After installing the replacement transistor, but before making any electrical connections, measure the resistance between the case of the transistor and the chassis, to ensure that the insulation is effective. The resistance measured should be greater than 10M.Reconnect leads to transistor and solder in place.

placement of Printed Circuit Board Protective Coating

WARNINGCONFORMAL COATING CONTAINS TOXICVAPORS! USE ONLY WITH ADEQUATE VEN-TILATION.

Clean repaired area of printed circuit board per instructions in the 5.3.2 CLEANING section of this manual.Apply Conformal Coating, Humiseal #1B-31 HYSOL PC20-35M-01 (Hu-miseal Division, Columbia Chase Corp., 24-60 Brooklyn Queens Express-way West, Woodside, N.Y., 11377) P/N 016-01040-0000.Shake container well before using.Spray or brush surfaces with smooth, even strikes. If spraying, hold nozzle 10-15 inches from work surface.Cure time is ten minutes at room temperature.

B KTR 908

Revision 9, Sept

I. Programmable Read Only Memory (PROM) ReplacementThe read only memory packages are specially programmed devices to provide specific logic outputs required for operation in the unit. The manufacturers part (type) number is for the un-programmed device, and cannot be used. The Honey-well part number must be used to obtain the correctly programmed device. Refer to SECTION VI ILLUSTRATED PARTS LIST).

5.3.3.1 REPLACEMENT OF COMPONENTS

This section describes the procedure, along with any special techniques, for replacing damaged or defective components.

A. ConnectorsWhen replacing a connector, refer to the appropriate PC board assembly drawing, and follow the notes, to ensure correct mounting and mating of each connector.

B. CryTherize

C. DioDionor

D. InteRef

E. WirWhpiecsoldthe/2004 15667M09.JA Page 5-25

stal use of any crystal, other than a Honeywell crystal, is considered an unautho-d modification.desdes used are silicon and germanium. Use long-nose pliers as a heat sink, under mal soldering conditions. Note the diode polarity before removal.grated Circuitser to the applicable reference for removal and replacement instructions.ing/Coaxial Cableen repairing a wire that has broken from its terminal, remove all old solder, and es of wire from the terminal, re-strip the wire to the necessary length, and re-er the wire to the terminal. Replace a damaged wire or coaxial cable with one of

same type, size and length.

B KTR 908

Revision 9, Sept

5.3.4 DISASSEMBLY

5.3.4.1 Transmitter

1. Remove the eight (8) countersunk screws from the top cover.2. Remove the two screws from the rear of the top cover.3. Unsolder the three color coded wires leading to the transmitter PC board. Note: Be-

fore removal note the locale of each wire.4. Unsolder the center conductor lead of the BNC connector at E502 on the transmitter

PC board.5. Remove all screws from the PC board. This includes those on the three transistors.6. Carefully wedge Q502 out of its socket while moving the PC board in an upward mo-

tion.

5.3.4.2 Receiver Board

1. Rem2. Rem

ary3. Wit

Caupins

5.3.4.3

1. Rem2. Rem3. Rem4. Rem

tran5. Rem

sink6. Rem7. Not

Unspar

8. Car

5.3.5 A

To assemble the care with the confor shorts, broken/2004 15667M09.JA Page 5-26

ove the right side cover via the two screws. Note: the unit is facing you.ove the five screws from the casting. Four of the screws are on the outer bound-

of the casting and the fifth screw is next to P304.h a pair of pliers gently pull from the center of the casting in an upward motion. tion: Exercise extreme care when replacing this board. Make sure that all the from P304, P303 and P301 align with the board.

Main Board

ove the side cover via the two screws.ove receiver board 5.3.4.2.ove the two screws that retains the connector via the bracket to the front plate.ove Power Supply cover for access to and remove the screws from the three

sistors mounted on the transmitter heat sink.ove the screw that holds the Posistor (R149) mounted to the transmitter heat

.ove the seven screws that hold the Main Board to the casting.

e exact location of each of 12 color coded wires and 2 wires of Resistor R149. older this end of each color coded wire. NOTE: Wires may be left in place for

tial removal (access to P.C. Board far side).efully work Main Board away from unit assembly.

SSEMBLY

individual units of the KTR 908 reverse the order of disassembly. Use extreme nector pins. Once the individual units are assembled make a visual inspection components, etc.

B KTR 908

Revision 9, Sept

5.4 TROUBLESHOOTINGThis troubleshooting section is intended as a guide for the technician in isolating a malfunction in the KTR 908. Before troubleshooting the radio, a thorough understanding of the Theory of Oper-ation should be accomplished. The technique (fault finding through elimination) should be used as a basis in locating the troubled area. The following steps should be performed before any trou-bleshooting procedures are applied. Refer to the applicable section of SECTION VI ILLUSTRAT-ED PARTS LIST

A. Perform a bench check to determine if the unit is the source of the problem.B. Determine the exact problem. C. If the problem is in the COMM, is it the receiver or is it the transmitter?

Once you have determined the problem section, consult the troubleshooting flow charts and sche-matics for information pertaining to voltages and waveforms.

5.4.1 POWER SUPPLY TROUBLESHOOTING

A. VeB. VeC. VeD. VeE. VeF. Ve

If voltages are pre13 of I103B has tIf the unit is not inschematics exist.

5.4.2 S

Verify reference f

5.4.3 TU

VCO Volt1. W

ap2. W

ap3. W

ap4. W

ap5. W

ap/2004 15667M09.JA Page 5-27

rify 27.5 volts at each end of fuse F101.rify +10 volts at CR107 cathode.rify +5 volts at cathode of CR108.rify -26 volts at anode of CR109.rify +9 volts at the collector of Q106.rify +185 volts at the collector of Q106.

NOTE:Use caution in measuring the voltage at the collectorof Q106.

sent but low, verify that the power supply is not in current limiting. Verify that pin he waveform depicted on the schematic. current limiting, first verify that all voltages and waveforms as depicted on the

YNTHESIZER FREQUENCY COMM

requency 12.8MHz at pin 15, I102.

NING VCO VOLTAGE

ageith the "use" frequency at 135.97MHz receive, the voltage at TP404 should be proximately 10 volts.ith the "use" frequency at 118.00MHz receive, the voltage at TP404 should be proximately 5.5 volts.ith the "use" frequency at 118.00MHz transmit, the voltage at TP404 should be proximately 3.5 volts.ith the "use" frequency at 126.97MHz receive, the voltage at TP404 should be proximately 7.5 volts.ith the "use" frequency at 151.97MHz receive, the voltage at TP404 should be proximately 14 volts. (Not on all units).

B KTR 908

Revision 9, Sept

5.4.4 COMM LOCAL OSCILLATOR

A. Verify that the LO level is more than 0.5 volt peak-to-peak at R406 with an oscillo-scope.

B. Verify that the LO is 11.4MHz above the desired frequency with a frequency counter.

5.4.5 DETECTOR

Verify the waveform at TP1 with 100uV, 30% modulation at 1KHz.

5.4.6 AGC AMPLIFIER

A. Set frequency at 126.97MHz at -70dBm (100uV).B. The voltage at I303C pin 14 is typically 5.0V with 100uV signal, 3.9 with no signal.C. The voltage at P304-4 is typically 6.9V with 100uV signal, 7.6V with no signal.

5.4.7 SQUELCH GATE

Verify approxima

5.4.8 A

With 100uV, 30%ume control clock

5.4.9 TR

Connect to a 50 oA. VeB. Ve

FIG/2004 15667M09.JA Page 5-28

tely 6.0V at emitter Q307 with 100uV, 30% modulation at 1KHz.

UDIO

modulated at 1KHz in the audio output should be 100mW minimum with the vol-wise (Unless R356 has been set for a different output level).

ANSMITTER

hm loadrify correct frequency at buffer output C399.rify the modulation waveform at the base of Q504.

URE 5-8 TRANSMITTER TROUBLESHOOTING FLOWCHART

B KTR 908

Revision 9, Sept

FIGU/2004 15667M09.JA Page 5-29

RE 5-9 POWER SUPPLY TROUBLESHOOTING FLOWCHART

B KTR 908



B KTR 908 Revision 9, Sept/2004 15667M09.JA Page 5-31

FIGURE 5-10 COMM RECEIVER TROUBLESHOOTING FLOWCHART

B KTR 908

Revision 9, Sept

SECTION VIILLUSTRATED PARTS LIST

6.1 GENERALThe Illustrated Parts List (IPL) is a complete list of assemblies and parts required for the unit. The IPL also provides for the proper identification of replacement parts. Individual parts lists within this IPL are arranged in numerical sequence starting with the top assembly and continuing with the sub-assemblies. All mechanical parts will be separated from the electrical parts used on the sub-assembly. Each parts list is followed by a component location drawing.Parts identified in this IPL by Honeywell part number meet design specifications for this equipment and are the recommended replacement parts. For warranty information concerning Honeywell re-placement parts, consult the www.bendixking.com website.Some part numbers may not be currently available. Consult the current Honeywell catalog or con-tact a Honeywell

6.2 REThe manual will b

6.3 LIS

Abbreviation

B

C

CJ

CR

DS

E

F

FL

FT

I

J

L

M

P

Q

R/2004 15667M09.JA Page 6-1

representative for equipment availability.

VISION SERVICEe revised as necessary to reflect current information.

T OF ABBREVIATIONS

Name

Motor or Synchro

Capacitor

Circuit Jumper

Diode

Lamp

Voltage or Signal Connect Point

Fuse

Filter

Feedthru

Integrated Circuit

Jack or Fixed Connector

Inductor

Meter

Plug

Transistor

Resistor

B KTR 908

Revision 9, Sept

RT Thermistor

S Switch

T Transformer

TP Test Point

U Component Network, Integrated Circuit,Circuit Assembly

V Photocell/Vacuum Tube

W Waveguide

Y Crystal

Abbreviation Name/2004 15667M09.JA Page 6-2

B KTR 908

Revision 9, Sept

6.4 SAMPLE PARTS LIST

The above is onlyumn, when showThis information da lack of this colu/2004 15667M09.JA Page 6-3

a sample. The actual format and style may vary slightly. A Find Number col-n, references selected items on the BOMs accompanying Assembly Drawing. oes not apply to every BOM. Therefore, a lack of information in this column, or mn, should not be interpreted as an omission.

FIGURE 6-1 SAMPLE PARTS LIST

B KTR 908



B KTR 908

Revision 9, Sept

6.5 KTR 908 FINAL ASSEMBLY

PN DESCRIPTION REV-----------------------------------------------------------------------064-1023-00 FINAL ASSY 25K SEL AB064-1023-01 FINAL ASSY 50K SEL AB064-1023-02 FINAL ASSY 25K BB AC064-1023-03 FINAL ASSY 50K BB AA

--------------------------------------------------------------------------------------------SYMBOL PART NUMBER FIND NO DESCRIPTION UM -0000 -0001 -0002 -0003--------------------------------------------------------------------------------------------Q101 999-09999-0099 DO NOT USE RF . .00 .00 . 057-02185-1000 S/N TAG FLVR SLVR EA 1.00 . . . 057-02185-1001 S/N TAG FLVR SLVR EA . 1.00 . . 057-021 057-021 057-022 057-022 057-022 057-022 057-024 057-024 057-024 064-102 200-062 200-062 200-062 200-062/2004 15667M09.JA Page 6-5

85-1002 S/N TAG FLVR SLVR EA . . 1.00 . 85-1003 S/N TAG FLVR SLVR EA . . . 1.0003-0000 FLAVOR STCKR EA 1.00 . . . 03-0001 FLAVOR STCKR EA . 1.00 . . 03-0002 FLAVOR STCKR EA . . 1.00 . 03-0003 FLAVOR STCKR EA . . . 1.0028-0000 CLASS DECAL EA . 1.00 . 1.0028-0001 CLASS DECAL EA 1.00 . 1.00 . 28-0002 CLASS DECAL EA 1.00 1.00 1.00 1.003-99 COMMON BOM EA 1.00 1.00 1.00 1.0037-0010 MAIN BOARD EA . 1.00 . 1.0037-0030 MAIN BOARD EA 1.00 . 1.00 . 38-0003 RCVR 50KHZ BB EA . 1.00 . 1.0038-0020 RECEIVER, KTR 908 EA 1.00 . 1.00 .

B KTR 908

Revision 9, Sept

PN DESCRIPTION REV-----------------------------------------------------------------------064-1023-04 25K SEL W/SELCAL AB064-1023-05 50K SEL W/SELCAL AA064-1023-06 25K BB W/SELCAL AB064-1023-07 50K BB W/SELCAL AA

--------------------------------------------------------------------------------------------SYMBOL PART NUMBER FIND NO DESCRIPTION UM -0004 -0005 -0006 -0007-------------------------------------------------------------------------------------------- 057-02185-1004 S/N TAG FLVR SLVR EA 1.00 . . . 057-02185-1005 S/N TAG FLVR SLVR EA . 1.00 . . 057-02185-1006 S/N TAG FLVR SLVR EA . . 1.00 . 057-02185-1007 S/N TAG FLVR SLVR EA . . . 1.00 057-02203-0004 FLAVOR STCKR EA 1.00 . . . 057-02203-0005 FLAVOR STCKR EA . 1.00 . . 057-022 057-022 057-024 057-024 057-024 064-102 200-062 200-062 200-062 200-062/2004 15667M09.JA Page 6-6

03-0006 FLAVOR STCKR EA . . 1.00 . 03-0007 FLAVOR STCKR EA . . . 1.0028-0000 CLASS DECAL EA . 1.00 . 1.0028-0001 CLASS DECAL EA 1.00 . 1.00 . 28-0002 CLASS DECAL EA 1.00 1.00 1.00 1.003-99 COMMON BOM EA 1.00 1.00 1.00 1.0037-0011 MAIN BOARD EA . 1.00 . 1.0037-0031 MAIN BOARD,

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KTR 908

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