TM 11-6625-3041-12/TO 33A1-8-908-1
2-7.
LOOPBACK TESTING (cont)
On other end, connect timing output from path under test
q
back to timing input.
If an external STA CLOCK input is used, connect the station
q
clock signal from the path under test to SG-1139 STA CLOCK
input.
Set SG-1139 controls as follows:
POWER . . . . . ON
TIMING . . . . MASTER, LOOPED, or STA CLK as required
DATA RATE . As required
DATA IN indicator will be lit. TMG IN indicator (or STA
CLOCK indicator if external station clock signal is connected
to STA CLOCK input) will be lit. FAULT indicator will not
be lit. If indications are not proper, connections are impro-
per or path is faulty.
Press SINGLE ERROR several times:
q
ERRORS display will advance one count each time SINGLE
ERROR is pressed, which indicates setup is proper.
Press RESET DISPLAY:
q
Display will read 0. Display will remain O or will advance
count very slowly if path under test is operating properly.
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