8-66
ARMY TM 5-6675-238-14
MARINE CORPS TM 08839A-14/1
Table 8-8. Tape Reader Testing and Troubleshooting Procedure - Continued
Malfunction indication
Test procedure
Normal indication
corrective action
1g. Move take-up tape sensing
arm (right) to extreme right
(away from reading head)
1h. Press SPU MEMORY
switch-indicator to on
1i. Press SPU MEMORY
switch-indicator to off
1j. Press SPU REVERSE
indicator to on
LOAD
LOAD
switch-
1k. Remove A1 from card cage.
11.
Install A1 on card extender
and insert into A1 card cage
position
Press SPU ON switch-indicator
to on position. Connect digital
voltmeter (DVM) negative test
lead to ground (TB2 terminal
10; TP5), and positive test lead
to TB2 terminals 1 through 9
(TP16 through TP24) in order,
See figure 8-3, sheet 2, for lo-
cations of test points
1m. Set tape reader SPOOLING
1n.
10.
1p.
lq.
switch- S1 to DISABLE posi-
tion
Press SPU ON switch-indica-
tor to off
Press SPU ON switch-indica-
tor to on
Set tape reader SPOOLING
switch S1 to ENABLE
Connect DVM negative test
lead to ground (TB2 terminal
10; TP5) and positive test lead
to Al connector pins E, H, M,
P, R, S, W, X, and 2, one at a
time
1r. Press SPU ON indicator to off
The take-up (right) reel rotates If reel does not operate properly, per-
counterclockwise
form tests 2 and 3.2
The stepping motor sprocket ro-
NOTE
tates counterclockwise
Record and save results of step lj
The stepping motor sprocket ro-
N O TE
tates clockwise
If either test failed (step 1j or 1j), per-
form tests 2 and 4
See note at beginning of test 1
DVM indicates -0.2V or more Voltage out of tolerance: Perform teat 2
negative on all terminals
Reels stop rotating and lamp as- Same as step 1c
sembly bulbs go off
SPU ON switch-indicator goes off Refer to table 8-6
SPU ON switch-indicator lights
Refer to table 8-6
DVM indicates +3.0 to + 5.5V at Any voltage out of tolerance Insure that
each pin
the lamp assembly is lighted; then
perform tests 2 and 5
NOTE
If the tape reader appears to function properly mechanically and passes steps 11 and 1q, but does not pass the SPU
self-test (88 appears on FAILURE/ACTION indicator), then perform tests 2 and 5; otherwise, proceed to step 3.
2. POWER SUPPLY.
