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3-1
3. SERVICING HINTS
To prevent loose metal objects from getting in the CD
mechanism, it will be necessary to see to a ciean repair
station.
The objective can be cleaned with a blow brush.
When effecting repairs to, or making measurements on
the CD mechanism, be careful not to damage the flat
springs of the focusing unit.
THE PHOTODIODES AND THE LASER ARE MORE
SENSITIVE TO ELECTROSTATIC DISCHARGES THAN
MOS ICS.
CARELESS HANDLING DURING SERVICING MAY
REDUCE LIFE EXPECTANCY DRASTICALLY.
FOR THIS REASON CARE SHOULD BE TAKEN THAT
DURING SERVICING THE POTENTIALS OF THE AIDS
AND YOURSELF ARE EQUAL TO THAT OF THE
SCREENING OF THE SET.
-or measurements and adjustments it is possible to
d0sIition the working mechanism outside the set.
-or this purpose, an extension cable can be made from
he following parts.
-
Service flat cable (14-pole)
-
Service connector (14-pole)
4822 322 40066
—
4822 290 60602
"hese two items should be used to assemble an
»xtension cable between the connector and the flex
cable of the CDM-2 unit.
"he two connections to the motor should be lengthened
vith loose wires.
%emark: The service cable should be assembled as
follows; (see Fig. 1)
CDM
FLEX—CABLE
4822
290
60602
SOLDER
JOINT
4822
322
40066
Demounting the Rafoc unit
— Take the CD-mechanism out of the set.
(For the demounting instructions see the service
_ manual of the set).
— Remove the flexible PCB from the connector on the
PCB by lifting the upper part of the connector and
taking the flexible PCB out. (see Fig. 2)
MDA.00232
T22/48
Fin
2
— The RAFOC unit can be removed after the two fixing
screws M3 x 25 have been loosened.
Caution: when doing so, the two nuts M3 on the upper
side of the CD mechanism come loose.
— Now the pivot plate, item no. 56, can be removed.
— After removing the clamping piece, item no. 51, the
RAFOC unit/flexible PCB assembly can be taken out.
Attention: when mounting the RAFOC unit, see to it
that the flexible PCB reset weil against the mounting
plate at the height of the clamping piece (item no. 51).
In some cases, after exchanging the RAFOC
unit/flexible PCB assembly, it may be necassary to
|
glue the flexible PCB with a fast-drying glue to prevent
the RAFOC unit from rubbing against the flexible PCB.
The glueing shouid be done very carefully.
— When the laser and/or the monitor diodes are
defective, it will be necessary to replace the CDM unit.
— After mounting the RAFOC unit you should make sure
that the arm runs clear over the entire disc diameter.
This can be checked by means of a spring-pressure
&
2
x.
Ry
MDA.0031 1
'
621/T19
Fig. 1.
gauge which is held against the magnet of the focusing
unit.
The friction of the arm, measured over the entire meter
Service aids
Audio test disc
Disc without errors +
Disc with DO errors,
black spots and fingerprints
Disc hold-down
Torx screwdrivers
Set (straight)
Set (Square)
Glass disc
CS 9 486 %
4822 397 30085
4822 397 30096
4822 532 51755
4822 395 50145
4822 395 50132
4822 395 90204
reading, may not be greater than 25mN.
— A fast check of the clearance of the arm is possible in
service position 0.
For servicing positions see the service manual of the
set.
— After mouning, the angle setting should be adjusted.
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