Orban Optimod-AM 9400, Руководство по эксплуатации

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4-12
MAINTENANCE ORBAN MODEL 9400
previous tests may fail to detect faults in certain DSP chips. To verify that all of
the DSP chips are working correctly:
a) Connect the oscillator to both 9400’s analog inputs.
b) Navigate to
S
ETUP
> T
EST
and set the 9400’s operating mode to
O
PERATE
.
c) Recall the
G
EN
M
ED
preset.
d) Set the oscillator’s frequency to 400 Hz and its output level to create 10 dB
of gain reduction as indicated on the
AGC M
ASTER
gain reduction meter.
e) Connect the N&D test set to the 9400’s left Analog Output #1.
f) Navigate to
S
ETUP
> IO C
ALIB
> O
UTPUT
> A
NALOG
1 > S
OURCE
and set the
9400’s left Analog Output #1 to emit the analog AM signal.
g) Verify that combined noise and distortion are below 0.1%.
h) Repeat steps (f) and (g) for the right Analog Output #1.
i) Navigate to
S
ETUP
> IO C
ALIB
> O
UTPUT
> A
NALOG
1 > S
OURCE
and set the
9400’s left Analog Output #1 to emit the digital radio AM signal.
j) Verify that combined noise and distortion are below 0.1%.
k) Repeat steps (i) and (j) for the right Analog Output #2.
9. Return OPTIMOD-AM to service.
A) Remove the 600

resistors connected across the outputs.
B) Restore your normal operating parameters, using the notes you made in step
(1.B) on page 4-7.
C) Navigate to S
ETUP
> T
EST
> M
ODE
and choose O
PERATE
.
D) Recall your normal operating preset.