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4-2
-
service posHion "2"
To be attained by pressing the "NEXr key after
service position
"1" is
reached. The Indication "0002"
appears on the display. Make sure that the rafoc unit
is within the reach of the disc. If a disc is put on the
turntable in this position, the working of the decoder
(MC signal) and the turntable motor control can be
checked (turntable motor is running at the right
speed). Laser control, focus control and turntable
motor control are active. This position is very suitable
for measurements of the turntable motor control. If
the HF-signal Is not well coded or if no disc is
present, the turntable motor will start rotating at
maximum speed.
-
Service position
"3"
To be attained by pressing the "NExr key after
service position "2" is reached. The indication "0003"
appears briefly on the display. Then the normal
standby display is shown. The set is now in the 2
nd
standby
position. All keys have their original function
again. In case of deviations an extensive
error
indication
takes place via the display.
-
If the
µP
observes a system error, a system error
Indication will appear on the display: Er 01 to
Er
08.
-
If the
µP
observes an
operating error,
an operating
error indication will appear on the display for
1.5
sec.:
Er 30 to
Er
37 and
Er 60
to Er
61.
For an explanation of the error indications: see Error
table.
The service program can be abandoned by turning the
mains switch (POWER ON/OFF) off and on again
(Hardware reset).
CS 11
950 1GB
Specification measurement
CO PLAYER
"'-----1
FILTER
t-------:R="
Fig. 4
!VN AND
DISTORTION
METER
•-G·
SOU NC TECl!NOLOGV
ST 1700B
30 '59 A12
To measure the specification use can be made of audio
test disc 4822 397 30095.
Use 13th order filter 4822 395 30204 to measure (see
Fig.4):
- Total harmonic distortion (THD)
- Intermodulation distortion
- Signal-to-noise ratio (S/N)
Continuous burning of the laser
See initiation of the Servicing programm
Service position "O"
Note:
Danger
Invisible laser radiation.
Avoid direct exposure to beam.
Check of the laser supply
The laser and, the laser supply in IC6525 plus the
monitor diode form a feedback system.
A defect in the laser supply can result in the destruction
of the laser.
If, in that case, the laser (= complete CDM2 unit) is
replaced, the new laser will also become defective.
However, it is impossible to check and repair a feedback
system if a link Is missing. The laser supply can be
checked with the circuit below. The green LED replaces
the laser, the voltage across the
18
Ohm resistor is feed
back as monitor voltage, the 33 Ohm resistor and the
switch serve to draw more current from the laser supply .
..---------<>
to
LO
.__ _ _ _ _ _ ---a
to
..L
Fig.
5
LED GREEN e.g. COY 94 IV
CONNECTED
DIRECTLY
TO PANEL
42 444 A12
5322 130 32182
The above circuit Is connected to the connector on the
main
panel·
via an extension cable instead of a flex print.
The normal flex print is not suited for this purpose
because of its high internal resistance.
Code no. extension cable 4822 322 40066
C
C
(
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