JVC PD-35DX Service Manual page 39

3.8 ADJUSTMENT PROCEDURE
3.8.1 DISPLAY UNIT
Measuring
Item
instrument
PDP POWER DC voltmeter
SUPPLY
VOLTAGE Signal generator
Resistor
(5ohm ±20% /
5W)
Item CN0AU/CN0AT
measured Disconnected
Designated
Vs value for panel
±0.5V
Designated
value for panel
Vd
±0.5V
5V 5.25 ± 0.15V
CN0C4 (PDP POWER PWB: Chassis base)
Vs 1
NC 2
Vd 3
4
NC
5
5V
GND 6
Designated panel voltage Designated panel voltage
Vs/Vd voltage label Vs/Vd voltage label
R628
170V ADJ
Heat sink Heat sink
PDP POWER PWB PDP POWER PWB
LINE FILTER PWB LINE FILTER PWB
DANGER ! DANGER !
HAZARDOUS LIVE PARTS HAZARDOUS LIVE PARTS
Designated value for panel / layout of adjustment VR Designated value for panel / layout of adjustment VR
Test point Adjustment part
Connector Vs VR :170V ADJ
CN0C4 (R628)
[PDP POWER Vd VR : 60V ADJ
PWB] (R721)
CN0AU/CN0AT Adjustment
Connected
Designated
value for panel
±0.5V
Designated
value for panel
±0.5V
5.20 ± 0.15V
5Ω/5W /5W
(Load resistor) (Load resistor) 5V Vd
Fig.1
Voltage adjustment Voltage adjustment
VR (Vs, Vd) VR (Vs, Vd)
CN0C4
CN0AU
Connector for Connector for
adjustment adjustment
CN0AT
Fig.1 Fig.1
R721
60V ADJ
SYSTEM POWER PWB SYSTEM POWER PWB
AUDIO AUDIO
PWB PWB
Chassis Chassis
Base Base
(Rear view) (Rear view)
Fig.2
CAUTION:
During adjustment operation of PDP POWER SUPPLY
VOLTAGE, don't touch the heat sink of the PDP
POWER PWB. If you touch it, electric shock may be
caused. (See Fig.2)
<When PDP POWER PWB is not replaced>
(1) Connect the load resistor (5Ω/5W) to the CN0C4
connector on the PDP POWER PWB. (See Fig.1)
(2) Adjust Vs (170V ADJ) VR and Vd (60V ADJ) VR
such that the Vs and Vd load resistor voltage tally
with those in the table.
VR
(3) Ensure that the voltage between pins 5 and 6 of
CN0C4 (5V) coincides with the table's value.
R628
(4) Input a PAL (625i) all-black signal and check that
voltage coincides with the values in the table.
R721
(5) Readjust if the adjusted value is different from those
in the table.
-
NOTE:
Designated value for the panel is printed on a small
label on the top left corner at the back of the PDP.(See
Fig.2)
<When PDP POWER PWB is replaced>
CAUTION:
Before making adjustments, be sure not to turn on the
power when the CN0AT and CN0AU connectors are
connected, as this may cause the PDP to break down.
(1) Disconnect the CN0AT and CN0AU connectors on
the PDP POWER PWB.
(2) Connect the load resistor (5Ω/5W) to the CN0C4
Vs
connector and turn on the power.
(3) Adjust Vs (170V ADJ) VR and Vd (60V ADJ) VR so
that the Vs and Vd voltage coincides with the values
in the table.
(4) Ensure that the voltage between pins 5 and 6 of
CN0C4 (5V) coincides with the values in the table.
(5) Turn off the power, and connect the CN0AT and
CN0AU connectors and turn on the power again.
(6) Input a PAL (625i) all-black signal and check that it
coincides with the values in the table.
(7) If the adjusted value is different from those in the
table, fine-tune without unplugging the connectors.
CAUTION:
Designated power supply voltage of the panel (Vs, Vd)
varies according to the PDP unit. (See Fig.2)
Pay careful attention during adjustment, as any error in
procedure may cause the PDP to break down.
Description
(No.52089)1-39
PD-35DX