ii
CD PLAYER ADJUSTMENT PROCEDURES
BEFORE CHECKING OR ADJUSTING CD
PLAYER
1.
Procedures for all adjustments for the CD player from atart
to finish are described below.
2. The pick-up does not have to be adjusted if everything has
been checked and no problems were found.
CHECKING FOCUS ERROR SIGNAL
The effectiveness of the pick-up is determined by checking its fo-
cus error signal. This must be checked before any repairs are
performed on the CD player.
1.
Apply Power Switch to the set and press the STOP button.
2.
Short test terminal (CN15) TOFF pin to GND to turn the
tracking servo OFF.
3. Connect the oscilloscope to test point TP12 (focus
error) pinandto GND.
(Set the time at 0.5 Sec/DIV.)
4.
Press the OPEN/CLOSE button, place the test disc on
the table load, and then press the OPEN/CLOSE but-
ton once again.
5.
Once the disc is set, a waveform like that shown in
the illustration below will be repeated three times.
Check that the p-p voltage of this waveform is the
same above and below the horizontal axis at 3V.
Repeated three times
;=
------~----w---+-------------------
(Measured with a Memory Scope)
6,
7.
-4
Ov ---- -“” ---7----
iv ● p-p voitage of 3V
● + and – voltage roughly same
Press the OPEN/CLOSE button repeatedly to pull out
and Insert the disc until the waveform appears each
time the disc is inserted and removed.
If the resuits of the above procedure are not satis-
factory, the pick-up is damaged.
FREE RUN FREQUENCY ADJUSTMENT
1.
Connect the frequency counter to VCO test terminal
(CN5)
PCK test pin and to GND, (Use a 10:1 probe.)
2. Short the test point TP4 (OSC ON) pin to GND.
3. Apply Power Switch to the set and press the STOP
button.
4. Adjust the OSC coil T102 using a plastic screwdriver
until the frequency counter indicator
reads
4.3218 MHz+ 1OHZ.
SETTING OF INITIAL POSITION OF VOLUME
1.
Set the variable resistors to the initial positions listed
below:
P101 (FOCUS OFFSET) ................. Mechanical Center
PI02 (E/F BALANCE) .................... Mechanical Center
P103 (TRACKING OFFSET) ........... Mechanical Center
P104 (TRACKING GAIN) ..
At the position of 45° in the
clockwise from the Mechanical Center
P105 (KICK GAIN) ......................... Mechanical Center
P106 (LINEAR MOTOR OFFSET) .. Mechanical Center
P301 (FOCUS GAIN) ......... At the position of 45° in the
clockwise from the Mechanical Center
FOCUS OFFSET ADJUSTMENT
1, Apply Power Switch to the set and press the STOP button,
2. Connect a DC Voltmeter to the test terminal (CNI 1) F (fo-
cus coil) pin and short the test terminal (CN5) FOCS pin
to GND.
3. In this condition check that the DC Voltmeter indicator is
in the range – 0.5Vt50mV, and adjust PIOI if it Is not.
,1
TRACKING OFFSET ADJUSTMENT
1.
Appiy Power Switch to the set and press the STOP button.
2. Connect a DC Voltmeter to the test terminal (CN11) T
(tracking coii) pin and short the test point TP1l (T-OF) pin
to GND.
3. in this condition check that the DC Voltmeter indicator is
in the range 100mV~50mV, and adjust P103 if it is
not.
NOTE:
Perform this adjustment once again after adjusting the
E/F BALANCE and TRACKING GAIN signals.
LINEAR MOTOR OFFSET ADJUSTMENT
1. Apply Power Switch to the set and press the STOP button.
2. Connect a DC Voltmeter to the test terminal (CN7) LIN-
EAR MOTOR pin.
3. in this condition check that the DC Voltmeter indicator is
in the range OVk100mV, and adjust P106 if it is not.
E/F BALANCE ADJUSTMENT
1.
Place the test disc (Modern Wave II) on the table load,
and play the fourth item on the disc. Short the test point
TP2 (TEST) pin to GND, and test terminal (CN15) TOFF
pin to GND to turn tracking servo OFF.
2,
Connect a DC Voitmeter and an oscilloscope via the low-
pass, filter like that shown in the illustration below to the
test terminal (CN15) TE (tracking error) pin.
6No~6N’ )
#
Measurement circuit
3. Adjust P102 so that the DC Voltmeter reading is
OVA15mV (oscilloscope waveform is symmetric to + and j
– about the zero level).
–6–
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