TB 9-6625-1138-24
(6) Repeat (3) above.
(7) Slowly decrease calibrator frequency until AFC circuit loses control. If counter
indication is less than 3.3 ms, perform b below.
b. Adjustments (fig. 1)
(1) Set MODE SELECTOR switch to NORMAL.
(2) Connect multimeter positive lead to center tap (wiper arm) of R129 and negative
lead to chassis ground.
(3) Adjust R129 for a -1 V dc indication on multimeter (R).
(4) Remove positive lead from R129 and reconnect to center tap of R131.
(5) Adjust R131 for a -1 V dc indication on multimeter (R).
(6) Repeat a (4) through (7) above.
13. Power Supply
NOTE
Do not perform power supply check If all other parameters are
within tolerance.
a. P e r f o r m a n c e C h e c k . C o n n e c t m u l t i m e t e r p o s i t i v e l e a d t o e m i t t e r o f
Q 2 0 (SOCKET) (fig. 1) and negative lead to chassis ground. If multimeter does not
indicate between -14.8 and -15.2 V dc, perform b below.
b. Adjustments.
Adjust R160 (ADJ -15 V) (fig. 1) for a -15 V dc indication on
multimeter (R).
14. Final Procedure
a. Deenergize and disconnect all equipment.
b. Annotate and affix DA label/form in accordance with TB 750-25.