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GENERAL SAFETY CHECKS
•
High voltage BEAB test to confirm components across barrier (including sub board).
•
Deg relay insertion orientation test (relay can be fitted inverted on main and sub PSU console stand). + Job instruction to
show orientation of relay.
SUB BOARD PSU CHECK (DTT/BASS/CONSOLE PSU)
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Short circuit test (all rails)
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Output voltage test (all rails), see table.
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Standby operation. All rails should be off. +10V remains to supply, sub PSU & opto.
•
Full load operation check.
RAIL
DTT
BASS
38V
/
0.62A
32V
/
/
9V
400mA
/
5.1V
1.5A
Used for mute
3V3
2.7A
/
30V
10mA
/
12V
10mA
/
DTT +5V SETTING
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Set VR1 to approx. centre position (10kΩ).
•
Turn power on applying external load, see table.
•
Adjust VR1 making sure +5.2V rail is within ± 0.05V.
SUB-BOARD MUST BE BEAB TESTED IN A SET OR CONSOLE STAND.
HIGH VOLTAGE LIMITER CIRCUIT CHECK
•
Mount the PW board to the set and adjust normally.
•
Receive the circle pattern signal.
•
Set the contrast and brightness to maximum.
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Add R=470K in parallel with R718 and R718A.
•
Check that picture and sound disappear when R is added.
NOTE:
High voltage limiter circuit jig:
ANODE/FOCUS SHORT-CIRCUIT TEST PROTECTION CIRCUIT CHECK
•
Add a dc voltage to R760 until set trips ( The dc level should be equivalent to 1.7 x (+B current peak value )
0.6 VDC R760 SET SHOULD NOT TRIP
1.6 VDC R760 SET SHOULD TRIP
FINAL ANODE VOLTAGE LEVEL CHECK.
Please check on all A8 models that the final anode voltage does not exceed the voltages stated.
28" widescreen
32" widescreen
This test should be carried out with the brightness and the contrast set to minimum.
All manuals and user guides at all-guides.com
CONSOLE
0.62A
0.92A
/
Used for mute
/
/
/
25",28"
28" 16/9
32" 16/9
31kV
32kV
6
R719
R749
2
47K
4K7
47K
4K7
47K
4K7
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