TM 11-6625-3053-14
ITEM
MALFUNCTION
CHECKS/CORRECTIVE ACTION
g) Using multimeter, check voltage between test pin 6 (ground) and
test pin 3 on the A2A3 card assy.
Voltage should measure -325V +/- 1 VDC.
If this voltage is not obtained, go to check 2 below.
If this voltage is obtained, check the wiring between pin 3 on
A2A3 and the -325TP on the tuning head tracking board. Repair
as required.
2. Output filter circuit check.
a) Using multimeter, measure voltage between test pin 6 (ground)
and the negative side of C1 on the A2A3 card assy.
Voltage should be approx -326 VDC.
If this voltage is not obtained, go to check 3 below.
If this voltage is obtained, check L1, C6 through C9 and R5
through R8. Replace defective components.
3. Input filter check.
NOTE
Next measurement is in volts AC.
a) Using multimeter set to 1000 VAC, measure voltage across test
pins 1 and 2 on the A2A3 card assy.
Voltage should be approx 364 VAC.
If this voltage is not obtained, go to T/S item 8.
If this voltage is obtained, check CR1 through CR4, C1 through
C4, R1 through R4, C5 & R14. Replace defective components.
8
A2 Power Supply Assembly Check.
1. A2 assy output check.
a) Using multimeter set to 1000 VAC range, measure voltage across
the following pins: Note typical voltages to the right of the points.
1 and 2 of A2A3 card assy 364 VAC
1 and 2 of A2A1 card assy 588 VAC
9 and 10 of A2A1 card assy 20 VAC
If these voltages are not obtained, go to check 2 below.
6-58