TM 11-6625-3053-14
ITEM
MALFUNCTION
CHECKS/CORRECTIVE ACTION
b) Measure voltage between test pins 1 and 2 of A2A2 card assy.
Voltage should measure approx 10.8 VAC.
If voltage is obtained, individually check CR1 through CR4 for
directional conductivity, and check individually C1 and C2 for non
shorted state. Replace faulty components.
If voltage is not obtained, check main input transformer T1 per
T/S item 12.
11
Grid Voltage Faulty.
1. Grid supply output check.
a) Remove instrument dust cover (para 6-20) and high voltage
supply cover, (para 6-22) if on.
b) Set sig gen to initial settings of para 2-4 and energize.
c) Wait 2 mins and set MODULATION Switch to CW.
d) Using multimeter, set to 1000 VDC range and measure voltage
between ground and test pin 17 on A2A2 card assy.
Voltage should measure approx -317.5 VDC.
If voltage is obtained but was not obtained when measured on
tracking board, check wiring between A2A2 card and the tuning
head.
If voltage is not obtained, go to check 2 below.
2. Check voltage at pin 12.
a) Continuing with multimeter as set. Measure voltage between
chassis ground and test pin 12 of A2A2 card assy.
Voltage should be -345 VDC.
If voltage is obtained, go to check 3 below.
If voltage is not obtained, go to check 6 below.
3. Check L1.
a) Continuing with multimeter as set, measure voltage at the
junction of L1 and R9.
Voltage should be approx. -345V.
If voltage is obtained, replace L1.
If voltage is not obtained, go to check 4 below.
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