TM 11-5821-333-30
6-20. OPERATIONAL CHECK. Continued
ACTION
RESPONSE
Step 7. REFERENCE RT SC XMT DIGITAL TEST
Presets:
SET TEST ADAPTER–
SET FUNCTION GENERATOR–
S1:9
FUNCTION: SQUARE
S3: OFF
FREQ: 1kHz (990 to 1010 Hz)
SET FREQ COUNTER INPUT TO 1 Mfl AND THEN
FUNCTION GENERATOR LEVEL TO 10 V P-P (9 TO
11 v P-P)
Connect Xl probe to TP9, set PTT switch
Scope channel 1 displays square wave:
(S8) to REF, and hold.
1 kHz (990 to 1010 Hz)
Duty cycle same as square wave on
scope channel 2. (voltage may not be
the same)
If not, go to chart 7.
Step 8. REFERENCE RT SC RCV AUDIO TEST
Presets:
SET REF RT–
SET SIGNAL GENERATOR–
FUNCTION: SQ OFF
FREQ: 30 MHz
LEVEL: -60 dBm
SET TEST ADAPTER–
FM MODE: INT
S1: OFF
MODULATION: 1 kHz at 6 to 7 kHz deviation
CONNECT:
SIGNAL GENERATOR OUTPUT TO J10, AFTER REMOVING JUMPER W1 FROM J10 AND
J11.
Connect ext probe to TP11 .
Scope channel 1 displays 5 TO 11 V P-P level.
If not, replace reference rt. If still bad, use
troubleshooting schematics 4 and 5.
Step 9. REFERENCE RT SC RCV DIGITAL TEST
Connect ext probe to TP10.
Scope channel 1 displays a 5 to 11 V P-P sig-
nal.
If not, replace reference rt. If still bad, go to
troubleshooting schematic 7.
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