JVC PD-50X795 Service Manual page 34

4.7.2 POWER CIRCUIT [DISPLAY UNIT: PD-50X795]
Measuring
Item
instrument
PDP POWER Signal
VOLTAGE generator
DC voltmeter
MAIN POWER UNIT voltage adjustment point
CN806
1. Vs
2. Vs
3. Vs
4. NC
5. GND
6. GND
7. GND
8. GND
9. Va
10. Va
GND
GND
GND
GND
Voltage label
MODEL:PDP50x2xxxx
ALL Voltage:DC5V
Va:xxV Vs:xxxV
Max Watt:xxxW
1-34 (No.YA100)
Test point Adjustment part
Connector Vs VR:190V ADJ (R551)
CN806 Va VR:60V ADJ (R351)
Vs [MAIN POWER UNIT]
Va
[MAIN
POWER
UNIT]
R551
Vs
R531
Va
Voltage adjustment VR
Fig.1
CN806
Vs 1
Vs 2
Vs 3
Vs
NC 4
5
6
7
8
Va
Va 9
Va 10
Fig.2
MAIN POWER UNIT
Fig.3
Description
CAUTION:
• During adjustment operation of PDP POWER
VOLTAGE, don't touch the heat sink of the MAIN
POWER UNIT. If you touch it, electric shock may
be caused.
< When MAIN POWER UNIT is not replaced >
(1) Connect the DC voltmeter to the
connector and turn on the power. (See Fig.2)
(2) Adjust Vs (190V ADJ) VR and Va (60V ADJ) VR
so that the Vs and Va voltage coincides with the
values in the voltage label.
(3) Input a NTSC all-black signal and check that it
coincides with the values in the voltage label.
(4) Readjust if the adjusted value is different from
those in the voltage label.
NOTE:
• Designed value for the panel is printed on a label
on the upper-left at the back of the PDP. (See
Fig.3)
< When MAIN POWER UNIT is replaced >
CAUTION:
• Before making adjustments, be sure not to turn
on the power when the
connectors are connected, as this may cause
the PDP to break down.
(1) Disconnect the CN805
on the MAIN POWER UNIT.
(2) Connect DC voltmeter to the
and turn on the power. (See Fig.2)
(3) Adjust Vs (190V ADJ) VR and Va (70V ADJ) VR
so that the Vs and Va voltage coincides with the
values in the voltage label.
(4) Turn off the power, and connect the
CN806 connectors and turn on the power again.
(5) Input a NTSC all-black signal and check that it
coincides with the values in the voltage label.
(6) If the adjusted value is different from those in
the voltage label, fine-tune without unplugging
the connectors.
CAUTION:
• Designated power supply voltage of the panel
(Vs, Va) varies according to the PDP unit.
• Pay careful attention during adjustment, as
any error in procedure may cause the PDP to
break down.
CN806
CN805 and CN806
and CN806 connectors
CN806 connector
CN805 and