Nakamichi PDP-42 User manual

1
Service Manual
PDP-42
Plasma Display System
CONTENTS
1. GENERAL .............................................................................................................2
2. DISPLAY PANEL ................................................................................................... 3
2-1 Location of Major Parts ................................................................................. 3
2-2 Removal Procedures ..................................................................................... 4
3. VIDEO PROCESSOR / CONTROL UNIT.............................................................. 6
3-1 Location of Major Parts ................................................................................. 6
3-2 Removal Procedures ..................................................................................... 6
3-3 A/D Converter Level Adjustment..................................................................7
4. MECHANICAL ASS’Y and PARTS LIST (Display Unit) ...................................... 8
5. ELECTRICAL PARTS LIST (Display Unit)......................................................... 11
6. MECHANICAL ASS’Y and PARTS LIST (Control Unit) .................................... 12
7. ELECTRICAL PARTS LIST (Control Unit)......................................................... 14
8. PACKAGE ASS’Y AND ACCESSORY KIT......................................................... 17
9. DESKTOP STAND PARTS LIST ........................................................................17
10. RECOMMENDED SPAER PARTS LIST .............................................................18
11. IC BLOCK DIAGRAMS ....................................................................................... 19
12. SPECIFICATIONS ...............................................................................................27
For Schematic Diagrams, and Mounting Diagrams, see the separate volume.
Power
InputSelector
PC/ RGBAV5 AV 6 AV7 DVD1AV3 AV 4AV1
Power AV2
Front
Europe
InputCall
DVD2
Standby/On
PDP-42
PushOpen

Front Component S-Video
Plasma Display System
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1.GENERAL
1.5 Precautions concerning the DISPLAY PANEL
1. Never lay the DISPLAY PANEL directly on a table.
Placing the display panel directly on the table may
cause serious damage to the DISPLAY TUBE.You
must place a sponge pad (or some other soft ma-
terial) on the table first then place the DISPLAY
PANEL on top of the pad.
2. Never carry or move the DISPLAY PANEL alone.
At least two people should be used to move it.Add-
ing too much stress to the DISPLAY PANEL may
cause serious damage to the DISPLAYTUBE. Use
extreme caution when handling.
3. As the DISPLAY TUBE is a vaccum tube, never
damage the neck (protruding) part of the tube.
Use exreme caution when handling (the DISPLAY
BLOCK is an extremely expensive piece of equip-
ment).
SPONGE PAD
DISPLAY PANEL
1.1 Product Code
R535: PDP-42
R554: PDP-42 Display Unit
R555: PDP-42 Control Unit
N935: PDP-42 Accessory Kit
N225: PDP-42 Stand Ass’y
1.2 Destinations
CAN, CH, DA, EP, HK, JPN, OTR, TW, UK, USA,
Abbreviations
CAN - Canada CH - China
DA - South America EP - Europe
HK - Hong Kong JPN - Japan
OTR - Other TW - Taiwan
UK - United Kingdom USA - U.S.A.
1.3 Cautions / Warnings
(1) Product Safety Notice
Parts marked with the symbol in the schematic
diagram have critical characteristics.
Use ONLY replacement parts recommended by the
manufacturer. It is recommended that the unit be op-
erated from a suitable DC supply or batteries during
initial check-out procedures.
(2) Leakage Current Check / Resistance Check
Before returning the unit to the customer, make sure
you make either (1) a leakage current check or (2) a
line to chassis resistance check. If the leakage cur-
rent exceeds 0.5 miliamp, or if the resistance from
chassis to either side of the power cord is less than
240 k ohms, the unit is defective.
1.4 Precoutions in Repairing
1. When the base is removed for repair or adjustment,
be sure that there are no metal objects in the nar-
row gap between the P.C.B. assembly or the me-
chanical part and the base.
2. When soldering the Microprocessor and Video sig-
nal processing ICs, use a ceramic soldering iron or
a soldering iron whose metal part is grounded since
they are not resistant to static electricity.
3. Make sure that wires do not contact heat produc-
ing parts.
4. Check that replaced wires do not contact sharp
edged or pointed parts.
5. Make sure that foreign object (screws, solder drop-
lets etc.) do not remain inside the set.
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2. DISPLAY PANEL
2-1 Location of Major Parts
Fig.2-1 FrontView
Fig.2-2 FrontView (under the DISPLAY BLOCK)
DISPLAY TUBE
COOLING FAN COOLING FANCOOLING FAN
FAN-A PCB FAN-B PCB
CONNECTION PCB POWER SW PCB FILTER PCB
POWER SUPPLY-2
PCB POWER SUPPLY-1 PCB REMOTE SENSOR-2 PCB
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DISPLAY PANEL
2-2 Removal Procedures
2-2-1. REAR COVER
Fig.2-3
(1) Remove the 20 ascrews (⇨marked) on the REAR
COVER.
(2)Remove the 6 bscrews (➡marked) on the REAR
COVER.
(3)Carefully remove the REAR COVER from the
DISPLAY PANEL.
2-2-2. FRONT COVER
1) Place the DISPLAY PANEL face up on the sponge
pad.
2) Remove the 16 retaining screws (top & bottom : 5
each, left & right : 3 each).
Fig.2-4
3) Carefully lift up and remove the FRONT COVER.
2-2-3. Removal of the DISPLAY BLOCK
1) Place the DISPLAY PANEL on the sponge pad so
that the front is facing down.
2) Remove the 4 retaining screws (⇨marked) on the
left side POWER SUPPLY-2 PCB and move the
PCB to remove the 3 connectors on the base.
Fig.2-5
3) Remove the 8 retaining screws (➡marked) that
secure the DISPLAY BLOCK.
4) Carefully lift the chassis straight up to remove the
DISPLAY BLOCK.
5) If DISPLAY BLOCK replacement is necessary, use
extreme caution not to break the protruding part of
the DISPLAY TUBE.
Fig.2-6
::
POWER SUPPLY-2 PCB
CONNECTOR
: A SCREW : B SCREW
Protruding part of the tube
DISPLAY BLOCK
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2-2-4. Reassembling the DISPLAY BLOCK
1) Reassemble in the reverse order for installation.
Special notes before placing the chassis on the
DISPLAY BLOCK !
When placing the chassis on the DISPLAY BLOCK,
use extreme caution not to break the protruding part
of the DISPLAY TUBE as shown in Fig.2-6.
2) When placing the FRONT COVER on the display
block, connect the lower side first (taking care to
avoid damaging the REMOTE SENSOR-2 PCB), but
do not push all the way down yet.
Then connect the upper side of the FRONT COVER
to the display block by inserting the two thin metal
plates (they look like a pair of bookends) between
the chassis and the FRONT COVER (aand bpart).
Fig.2-7
Next carefully press the upper and lower FRONT
COVER until the FRONT COVER completely engages
to the chassis of DISPLAY BLOCK.
Cautions:
1) When moving the DISPLAY BLOCK, do not hold
the glass section of the DISPLAY TUBE when
doing so as this may damage the glass.
2) Please be sure to wipe off any dust that may
have collected on top of the DISPLAY TUBE
before attaching the FRONT COVER to the DIS-
PLAY BLOCK.
AB
FRONT COVER
CHASSIS OF
DISPLAY BLOCK
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