TM 32-5835-005-14 & P
Section IV. DIRECT SUPPORT MAINTENANCE OF THE POWER SUPPLY
d. Test voltage at TP3 on A1A7. In-
7-7. General.
dication should be +15 VDC 1 VDC.
Before troubleshooting to correct an ob-
e. Test voltage at TP1 on AlA7.
served fault, the performance of the
Indication should be 1 volt of input
unit power supply must be verified.
line voltage.
Proceed as follows:
7-8. Disassembly Procedure.
f. Should any tests made in steps b.
through e. indicate voltages out of
a. Remove. Remove all power cables
range, replace board A1A7.
from the unit.
g. Repeat measurements b. through e.
b. Loosen. Remove unit top cover by
after replacement of A1A7. Should any
loosening captive screws.
tests now indicate voltages out of range,
refer to higher level of maintenance.
7-9. Power Supply Testing Procedure.
7-10. Repair.
a. Connect power cable to the unit
and activate the POWER ON switch to ON.
Repair of the power supply at the Direct
Support level is not authorized. Re-
b. Connect negative lead of multimeter
quest higher level of maintenance.
to the reference ground terminal TP2 on
logic board A1A6. (See Figure 7-1.)
c. With the positive lead of the mul-
timeter, test voltage at TP2 on power
supply card A1A7. Indication should be
+23 to +25 VDC.
Section V. DIRECT SUPPORT MAINTENANCE OF THE LOGIC CONTROL BOARD (A1A6)
c. Faulty take-up action.
7-11. General.
d. Improper foot switch operation.
Should any of the following symptoms/
malfunctions evidence themselves during
unit operation, probable cause is a
e. Unit will not go into RECORD/REP-
defective LOGIC CONTROL board (A1A6.)
RODUCE, FAST FWD, or REWIND modes of
operation.
a. Capstan motor fails to operate in
RECORD/REPRODUCE modes of operation.
f. Unit reproduces but does not re-
cord, or records but does not reproduce.
b. Capstan motor operates but there
is no tape motion.
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