Specifications

55
NO POWER OUTPUT
AT ANTENNA
B+
CURRENT
DRAW?
CHECK B+ ON
FINAL STAGES
B+ IS WITHIN
+/- 0.5V OF
DC-DC OUT?
1) CHECK FOR INCORRECT
OR DAMAGED PARTS IN
FINAL STAGES.
2) VERIFY B+ FEED CIRCUIT
INTEGRITY
(I.E. CONDITIONAL OPENS.)
CHECK RF OUTPUT
POWER AT C34
CHECK BIAS CIRCUITRY
IF OK
CHECK CONTORL
VOLTAGE
(COLLECTOR OF Q11)
OUTPUT
POWER
LEVEL
GOOD?
1) CHECK FOR INCORRECT
OR DAMAGED PARTS IN
FINAL STAGES.
2) VERIFY B+ FEED CIRCUIT
INTEGRITY
(I.E. CONDITIONAL SHORTS)
NO OR LOW B+
CURRENT
NO
1) CHECK PIN DIODES(D3, D5)
& TX_B2 VOLTAGE.
2) VERIFY CORRECT COMPONENTS
IN HARMONIC FILTER.
NO
HIGH B+
CURRENT
IS Q703
BIASED
PROPERLY?
IS
CONTROL
VOLTAGE
HIGH OR
LOW?
REPLACE
Q703
HIGH
TROUBLESHOOT POWER
CONTROL CIRCUIT AND/
OR VERIFY POWER SET
USING RV4.
LOW
INPUT
OF P.A.
STAGES
GOOD?
VERIFY INPUT OF P.A.
STAGES
(> +10DBM)
YES
YES
NO
YES
YES
P.A. STAGE(S) BAD:
1) VERIFY GAIN FROM INDIVIDUAL
P.A. STAGES.
2) REPLACE LOW/NO GAIN DEVICE(S)
VERIFY VCO OUTPUT
(> 0DBM)
VCO OUTPUT
GOOD?
BUFFER & DRIVER STAGE BAD:
1) VERIFY GAIN FROM EACH BUFFER
& DRIVER STAGE
2) REPLACE LOW/NO GAIN DEVICE(S)
TROUBLESHOOT
VCO
YES
NO
NO
DC-DC OUTPUT
1) SD-161 : 5.5V
2) SD-164 : 6.5V
3) SD-171 : 7.5V
4) SD-174 : 7.5V
(COLLECTOR Q11 > 5.0V)
( < 0.1A )
Figure 9.2. Troubleshooting Flow Chart for Transmitter