X-Ray Protector Adjustment/Check - JVC DT-V1710CG Service Manual

4.10.3 X-RAY PROTECTOR ADJUSTMENT/CHECK

X-RAY PROTECTOR ADJUSTMENT/CHECK
Measuring Instruments
Card (Slot)
Test Points
Adjustment Points
Note: Perform the following adjustment after completing the Screen Voltage Coarse adjustment.
(1) Turn the VR502 fully clockwise (the minimum position).
(2) Turn the VR501 fully counterclockwise (the minimum position).
(3) Set the CONTRAST and BRIGHT potentiometers on the front panel to the fully clockwise positions.
(4) Connect the high-voltage voltmeter to the anode of the CRT and turn the unit ON.
(5) Apply the 1080/60i all-white signal to INPUT A (Terminal Y on the Component/RGB Input Card).
(6) Turn the VR502 slowly counterclockwise until the value of the high-voltage voltmeter is 27.0 kV ± 0.2 kV.
(7) Connect the DC voltmeter across TP-XR and TP-GND.
(8) Turn the VR501 clockwise until the voltmeter reading is 5.5 V.
(9) Turn the VR501 slowly clockwise until the point at which the X-ray protector starts operation.
(The power turns off at the first operation and then turns on again 5 seconds later. At the second operation, the power turns off
and the LED of the INPUT SELECT D of the front panel blinks. When two operations are done consecutively, it stops at the
stand-by position.)
(10) Turn the VR502 slightly clockwise and turn the unit ON again.
(11) Turn the VR502 slowly counterclockwise and check the point at which the X-ray protector starts to operate.
Check that the high-voltage voltmeter value at which the X-ray protector starts to operate, is 27.0 kV ± 0.2 kV.
(12) Apply adhesive for fixing the VR501 in the adjusted position.
(13) Set the CONTRAST and BRIGHT potentiometers on the front panel to the center click positions.
(14) Turn the VR502 fully clockwise (the minimum position).
S. CORRECTION PWB
MAIN PWB
1-44 (No. 52152)
Signal generator (All-white signal)
High-voltage voltmeter
DC voltmeter
Component/RGB Input Card (Slot 1)
Anode of CRT
TP-XR, TP-GND [S. CORRECTION PWB]
VR501 (X-Ray Protector Adjustment VR) [S. CORRECTION PWB]
VR502 (High-Voltage VR) [S. CORRECTION PWB]
TP-XR
TP-G
Front side
(Top surface view of the S. CORRECTION PWB)
VR502
VR501
(Min)
(Max) (Min)
Front side
(Max)