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
4.2g. Connect oscilloscope chan-
Oscilloscope displays waveform A Voltage out of tolerance: Replace A2
nel A probe ground return
shown in figure 8-5
to ground (TB2 terminal 10,
Period T1 out of tolerance: Replace A2
TP5) and connect same
Period T2 out of tolerance: Perform cal-
channel A probe to A5 card
ibration procedure listed in test step
pin A, (Check that SPU RE-
5.1b. If cannot calibrate, replace A2
VERSE switch-indicator is
on by cycling the switch)
4.2h. Set SPOOLING switch S1
to DISABLE position
4.3 STEPPING MOTOR.
4.3a.
4.3b.
Use multimeter to measure Multimeter indicates 10 to 200 Resistance out of tolerance: Replace B1
resistance between A4 card
ohms
cage pins D and V (card ex-
tender must be used)
Use multimeter to measure Multimeter indicates 10 to 200 Resistance out of tolerance: Replace B1
resistance between A5 card
ohms
cage pins D and V (place
card extender in card cage
position A5)
4.4 DIRECTION AND MOTOR
DRIVE CONTROL
4.4a.
4.4b.
4.4c.
4.4d.
.
nel A probe ground return
shown in figure 8-5
to ground (TB2 terminal 10,
Reinstall A3 and A4 into
card cage
Jumper A5 card cage pins B
and C together. (Suggestion:
20 AWG solid wire into
card extender slot)
Jumper A5 card cage pins E
and H. Verify that SPU. RE-
VERSE switch-indicator is
on (switch-indicator must be
lighted) Also, check that
tape
reader SPOOLING
switch S1 is in the ENABLE
position
Connect oscilloscope than- Oscilloscope disdays waveform B Record and save test results for step 4.4n
TP5) and connect same
channel A probe to either
side of R9 on TB1 (TP35).
Refer to figure 8-3, sheet 2
of 2
8-71
