OPTIMOD-AM DIGITAL
MAINTENANCE
4-9
(1) + unreg.
(3) digital gnd
(5) +15V
(7) +5 V digital
(9) –5V analog
(2) - unreg
(4) chassis gnd
(6) -15V
(8) +5V analog
(10) NC
Table 4-2: Layout Diagram of J7, with expected voltages on each pin
The +3.3V and +2.5V supplies are locally regulated on the DSP and base
boards (see Section 6).
C)
Measure the regulated voltages at J7 with the DVM and observe the ripple
with an oscilloscope, AC-coupled. The following results are typical:
Power Supply Rail
DC Voltage (volts)
AC Ripple (mV p-p)
+15VDC
+15
0.5
<20
–15VDC
–15
0.5
<20
+5VDC
+5
0.25
<20
–5VDC
–5
0.25
<20
D5VDC
+5
0.25
[Obscured by noise]
Table 4-3: Typical Power Supply Voltages and AC Ripple
3.
Adjust Analog Output Level Trim.
A)
Verify 9400 software controls are set to their default settings. [Refer to step
(1.B) on page 4-7.]
B)
Feed the 9400 output with the built-in 400 Hz test tone:
a)
Navigate to
S
ETUP
>
T
EST
.
b)
Set the
M
ODE
to
T
ONE
.
C)
Connect the audio voltmeter to the Left Analog Output.
D)
Adjust output trim VR200 to make the meter read +10.6 dBu. (0 dBu = 0.775V
rms.) Verify a frequency reading of 400 Hz.
E)
Verify THD+N reading of <0.05% (0.02% typical) using a 22 kHz low pass filter
in the distortion analyzer.
F)
Set the
M
ODE
to
B
YPASS
.
B
YPASS
defeats all compression, limiting, and program equalization but
retains pre-emphasis.
G)
Verify a reading (noise) of <–80 dBu at the output of the unit.
H)
Using VR201, repeat steps (C) through (G) for the Right Analog Output.
4.
Check frequency response of Analog I/O.
A)
Verify 9400 software controls are set to their default settings. [Refer to step
(1.B) on page 4-7.]
B)
Be sure you are still in
B
YPASS
mode [see step (3.F)].
C)
Connect the oscillator to the Left Analog Input XLR connector.
Summary of Contents for Optimod-AM 9400
Page 1: ...Operating Manual OPTIMOD AM 9400 Digital Audio Processor Version 1 2 Software...
Page 7: ...Operating Manual OPTIMOD AM 9400 Digital Audio Processor Version 1 2 Software...
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Page 261: ...OPTIMOD AM DIGITAL TECHNICAL DATA 6 29...
Page 267: ...OPTIMOD AM DIGITAL TECHNICAL DATA 6 35 CPU Module...
Page 273: ...OPTIMOD AM DIGITAL TECHNICAL DATA 6 41 RS232 BOARD PARTS LOCATOR...
Page 275: ...OPTIMOD AM DIGITAL TECHNICAL DATA 6 43 8300 POWER SUPPLY PARTS LOCATOR...
Page 284: ...6 52 TECHNICAL DATA ORBAN MODEL 9400 DSP BOARD PARTS LOCATOR DRAWING 32170 000 14...
Page 292: ...6 60 TECHNICAL DATA ORBAN MODEL 9400 DISPLAY BOARD PARTS LOCATOR...
Page 293: ...OPTIMOD AM DIGITAL TECHNICAL DATA 6 61 DISPLAY BOARD...