Nakamichi PDP-42 Service Manual Digest - page 2
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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 DISPLAY TUBE. 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.