Orban Optimod-TV 8382, Руководство по эксплуатации

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4-8
MAINTENANCE ORBAN MODEL 8382
NOTE: Bypass defeats all compression, limiting, and program equaliza-
tion, but retains the selected pre-emphasis (either 50

s or 75

s).
BYPASS GAIN ....................................................................................0 dB
TONE FREQ....................................................................................400 Hz
TONE LVL........................................................................................ 100%
g) Press the N
EXT
button.
h) Set controls as follows:
TONE CHAN........................................................................................ L+R
2. Test the power supply
A) If the power supply is entirely dead and the fuse is not blown, verify that the
primary winding of the power transformer is intact by measuring the resis-
tance of the power supply at the IEC AC line connector.
For 115-volt operation, the resistance should be approximately 7.6

.
For 230-volt operation, the resistance should be approximately 27

.
Number of Red Flashes Problem With
1 + unregulated supply
2 +15V or –15V
3 +5V or –5V
4 +5V Digital
5
Analog

Digital ground connection broken
6 DSP A +3.3V supply
7 DSP B +3.3V supply
8 CPU +3.3V supply
9 CPU +2.5V supply
Table 4-1: Decoder Chart for Power Supervisor
B) The green LED power indicator on the lower left of the front panel monitors
the DC power supply outputs. If one or more power supply voltages are out of
tolerance, red flashes will report them according to Table 4-1. If there are
multiple values out of tolerance, they are reported one after another in a
continuous loop, with one green flash indicating the beginning of each count.
You can monitor power supply voltages at connector J7 on the power
supply board (see Section 6 for schematic and parts locator drawing).
When one faces the connector, the voltages can be found on the pins in
the following pattern:
(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: