Orban OPTIMOD 6300, Руководство по эксплуатации

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OPTIMOD 6300 DIGITAL MAINTENANCE
4-9
H) Using VR201, repeat steps (C) through (G) for the Right Analog Output.
4. Check frequency response of Analog I/O.
A) Verify 6300 software controls are set to their default settings. [Refer to step
(1.A) 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.
D) Inject the Analog Input XLR connector with a level of 0 dBu with the oscillator
set to 100 Hz.
E) Connect the audio analyzer to the 6300'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 20 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 6300 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
O
UTPUT
meter on the 6300 read
0
D
B
.
You will have to reduce the output level of the oscillator at higher fre-
quencies to compensate for the preemphasis boost in the 6300.
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%
20 kHz 0.015% 0.03%