TM 11-6625-3053-14
ITEM
MALFUNCTION
CHECKS/CORRECTIVE ACTION
11 4. Q1 check.
(cont'd)
a) Continuing with multimeter, set to 100 VDC range. Measure
voltage between pin 4 of U1 and test pin 12 of A2A2 card.
Voltage should be approx 0.
If reading is obtained, replace Q1.
If reading is not obtained, go to step 5.
5. U1 check.
a) Continuing with multimeter, set it to 100 VDC range.
b) Set MODULATION Switch to RF OFF.
c) Measure voltage between test point 10 and 9 of A2A2 card assy.
Voltage should be between 40 and 44 VDC.
If reading is obtained, replace U1.
If reading-is not obtained, go to T/S item 12, check 2.
6. Check input to grid supply.
a) Continuing with the multimeter, set to 100 VDC range.
b) Measure voltage between test pins 9 and 10 on the A2A1 card
assy.
Voltage should be approx 20 VAC.
If this reading is obtained, go to check 2 below.
If this reading is not obtained, go to T/S item 8.
7. Bridge circuit check.
a) Continuing with multimeter as set, measure voltage between pin
1 of AR2 and pin 12 on the A2A1 card assy.
Voltage should measure approx +21 VDC.
If voltage is obtained, go to check 8 below.
If voltage is not obtained, check CR11 through CR14, C5, and
C6. Replace faulty components.
8. AR2 check.
a) Set MODULATION to CW.
b) Continuing with multimeter as set.
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