4-10
MAINTENANCE
ORBAN MODEL 8300
D)
Inject the Analog Input XLR connector with a level of 0 dBu with the oscillator
set to 100 Hz.
This is 20 dB below the clip level, which allows headroom for pre-
emphasis. (75
s pre-emphasis will cause 17 dB of boost at 15 kHz.)
E)
Connect the audio analyzer to the 8300's Left Analog Output XLR connector.
F)
Verify a level of 0 dBu ±1 dB. Use this level as the reference level.
G)
Verify that frequency response at 50 Hz, 100 Hz, 400 Hz, 5 kHz, and 15 kHz is
within ±0.1 dB of the reference level.
This procedure tests the analog input circuitry, the A/D converter, the
DSP, the DAC, and the analog output circuitry.
H)
Repeat steps (C) through (G) for the right channel.
5.
Check distortion performance of Analog I/O.
A)
Verify 8300 software controls are set to their default settings. (Refer to page
4-7.)
B)
Be sure you are still in
B
YPASS
mode [see step (3.F)].
C)
Connect a THD analyzer to the Left Analog Output XLR connector. Set the
THD analyzer's bandwidth to 22 kHz.
D)
Connect the oscillator to the Left Analog Input XLR connector.
E)
For each frequency used to measure THD, adjust the output level of the oscil-
lator to make the
C
OMP
meter on the 8300 read
100
.
You will have to reduce the output level of the oscillator at higher fre-
quencies to compensate for the pre-emphasis boost in the 8300.
F)
Measure the THD+N at the frequency levels listed below.
Frequency
THD+N Typical
THD+N Maximum
50 Hz
0.015%
0.03%
100 Hz
0.015%
0.03%
400 Hz
0.015%
0.03%
1 kHz
0.015%
0.03%
2.5 kHz
0.015%
0.03%
5 kHz
0.015%
0.03%
7.5 kHz
0.015%
0.03%
10 kHz
0.015%
0.03%
15 kHz
0.015%
0.03%
G)
Repeat the above measurements for the right channel. Connect the oscillator
to the right analog input and the distortion analyzer to the right analog out-
put.
H)
Disconnect the oscillator and THD analyzer from the 8300.
Summary of Contents for 8300J
Page 1: ...Operating Manual OPTIMOD FM 8300 Digital Audio Processor Version 2 1 Software...
Page 7: ...Operating Manual OPTIMOD FM 8300 Digital Audio Processor Version 2 1 Software...
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Page 247: ...OPTIMOD FM DIGITAL TECHNICAL DATA 6 29...
Page 254: ...6 36 TECHNICAL DATA ORBAN MODEL 8300 CPU Module...
Page 260: ...6 42 TECHNICAL DATA ORBAN MODEL 8300 8300 RS232 BOARD PARTS LOCATOR...
Page 262: ...6 44 TECHNICAL DATA ORBAN MODEL 8300 8300 POWER SUPPLY PARTS LOCATOR...
Page 264: ...6 46 TECHNICAL DATA ORBAN MODEL 8300 8300 I O BOARD PARTS LOCATOR...
Page 270: ...6 52 TECHNICAL DATA ORBAN MODEL 8300 DSP BOARD PARTS LOCATOR DRAWING 32170 000 14...
Page 278: ...6 60 TECHNICAL DATA ORBAN MODEL 8300 8300 DISPLAY BOARD PARTS LOCATOR...
Page 279: ...OPTIMOD FM DIGITAL TECHNICAL DATA 6 61 DISPLAY BOARD...