ARMY TM 5-6675-238-14
MARINE CORPS TM 08839A-14/1
Table 8-6.1. PADS Test Set Self- Test Procedure Using Tape Reader, Part No. 877406-2 - Continued
Malfunction
Test procedure
Normal indication
indication/corrective action
c. If receive circuit bias current can-
not be adjusted as outlined above,
perform the following SPU short
circuit current test. Set meter up
to read current. Remove cable
W212 P1 from the front of the
SPU. Put positive ( + ) lead of me-
ter on pin 3 of J12 (TTY connec-
tor on front of SPU) and negative
(-) lead on pin 4 of J12. The
meter should indicate 30 mA ±10
mA. If meter does not indicate 30
mA, replace Al. If meter does
indicate 30 mA, replace or repair
TTY
TTY does not print out or prints out
incorrectly:
a. If the receive circuit bias current
is correct or can be adjusted, per-
form the send circuit test. Re-
move cable W212 P1 from SPU
and set meter up to read DC
volts. Place positive ( + ) lead of
meter on pin 2 of J12 (TTY con-
nector on front of SPU) and nega-
tive (-) lead of meter on pin 1 of
J12.
Meter
should
indicate
+ 30V. If meter does not indicate
+ 30V, replace Al. If meter does
indicate + 30V, set up meter to
read current. Place positive ( + )
lead of meter on pin 2 of J12
(TTY connector on front of SPU)
and negative (-) lead of meter on
pin 1 of J12. Meter should indi-
cate 39 mA ±3 mA. If meter does
not indicate 39 mA, replace A1.
If meter does indicate 39 mA,
proceed to next step
8-54.10
Change 1
