8-69
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
3. If. While observing DVM, man-
DVM indication varies continu-
Voltage range out of tolerance: Adjust
ually move tape
reader sup-
ously from 0 (-0/ + 4)V (low
R2 as follows: Loosen R2 body clamp.
ply (left front tape sensing
end) to +28 (-4/ + 0)V (high
Hold supply tape sensing arm approxi-
arm to its extreme left posi-
end)
mately midway between its extreme
tion (away from read head)
positions. Adjust R2 body for + 14V
DVM indication. Tighten R2 body
clamp. Repeat this test procedure
step; if voltage still out of tolerance,
replace R2. Voltage does not vary
continuously Replace R2
3.1g. Connect DVM negative test
lead to ground (TB2 termi-
nal 10; TP5) and positive
test lead to A6 card cage pin
D
3.1h. While observing
DVM, DVM indication varies continu-
Voltage range out of tolerance. Adjust
manually move tape reader
ously from 0 (-0/ + 4)V (low
R3 as follows: Loosen R3 body clamp.
take-up (right front) tape
end) to +28 (-4/ + 0)V (high
Hold supply tape sensing arm approxi-
sensing arm to its extreme
end)
mately midway between its extreme
right position (away from
positions. Adjust R3 body for + 14V
read head)
DVM indication. Tighten R3 body
clamp and repeat this test procedure
step; if voltage still out of tolerance,
replace R3.
3.li. Remove card extender and
reinstall A6 card in card
cage.
4. STEPPING MOTOR CIRCUI-
TRY.
4.1 CONTROL
INTERFACE
CHECK
4.1a. Remove A2, A3, A4, and AS
from card cage and mark ap-
propriate cards using mask-
ing tape for identification
during reinstallation; also,
cards are identified in figure
FO-19 and on side of card
cage.
Set tape reader
SPOOLING switch S1 to
ENABLE position
Voltage does not vary continuously Re-
place R3
