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(3) FOCUS GAIN ADJUSTMENT
1. Connect the servo gain adjuster to the player (see
page 55).
2. Set the servo gain adjuster's gain switch to position
"3" and the ON/OFF switch to ON.
3. Set up the AF oscillator output for 1 kHz, 150 mVp-p,
and connect it across the OSC and GND terminals on
the servo gain adjuster.
VOLT ia tae aise pag
Inputcoupling
...........
ccc cece eee eee
5. Play the test disc (SZZP1014F or SZZP1054C).
6. Set the servo gain adjuster's gain switch to position
"3", and you will see a 1 kHz signal on the oscillo-
scope. Adjust VR704 until the signal amplitudes on
both channels become
identical to each other.
. Set the gain switch back to position '2'.
(4) TRACKING
GAIN ADJUSTMENT
1. Set up the AF oscillator output for 1 kHz, 150 mVp-p,
and connect it across the OSC and GND terminals on
the servo gain adjuster.
VOLT?
aoa dae desi aens
Input coupling .............
cece cece eee
3. Switch the player power ON, and play the test disc
(SZZP1014F or SZZP1054C).
4. Set the servo gain adjuster's gain switch to position
"1", and
you will see
a 1 kHz signal on the
oscilloscope. Adjust. VR705 until the signal ampii-
tudes on both channels become identical to each
other.
. Set the gain switch back to position "2".
FOCUS OFFSET ADJUSTMENT
Note: Make sure that the servo gain adjuster's gain
switch is set to position "2".
1. Connect
the
oscilloscope's
CH.1
probe
across
ixaek) (+) and
(V-REF) on the Servo
P.C.B. and CH. 2 probe across
(+) and
iden (V-REF).
Oscilloscope setting:
1 V (CH. 2)
SWEEP
fe c ceatiohuce
tara oho ea ner
1 msec.
Input coupling
.......... AC (both CH. 1 and 2)
Trigger mode
.......... NORM (trigger CH. 1)
waveforms are observed. Adjust VR703 until the dip in
the RF signal envelope on CH. 1 is smooth and the
signal amplitude on CH.2 is minimized, i.e. when
amplitude A equals amplitude B.
-57-
"Adjust VR704 until a equals b.
"Adjust VR705 until a equals b.
(6) TRACKING
OF OFFSET ADJUSTMENT
Note: Make sure that the servo gain adjuster's gain
switch is set to position "2".
1. Connect
the
oscilloscope's
CH.1
probe
across
Gicek) (+) and
(V-REF) on the Servo
P.C.B. and CH. 2 probe across IfyZe¥] (+) and
fice) (V-REF).
Oscilloscope setting:
200 mV (CH. 1)
1 V (CH. 2)
1 msec.
input coupling
AC (both CH. 1 and 2)
Trigger mode
NORM (trigger CH. 1.)
. Switch the player power ON, and play rack 9 on the
test disc (SZZP1057C).
. Trigger the oscilloscope's CH. 1 so that the following
waveforms are observed. Adjust VR706 until the dip in
the RF signal envelope on CH. 1 is smooth and the
signal amplitude on CH. 2 is minimized,
i.e. when
amplitude A equals amplitude B.
Oscilloscope setting:
100 mV (CH. 1)
1 msec.
Input coupling
AC (both CH. 1 and 2)
Trigger mode
NORM (trigger CH. 2)
CHECK
OF PLAY OPERATION
AFTER ADJUSTMENT
*Checking Skip Search
1, Play an ordinary musical program disc.
2. Press the skip button to check for normal skip search
operation (in both the forward and reverse direc-
tions).
"Checking Manual Search
1. Play an ordinary musical program disc.
"Checking Using Defect Disc
1. Play the 0.7 mm black dot and the 0.7 mm wedge on
the defect test disc (SZZP1054C) and verify that no
sound skip or noise occurs.
2. Play the middle tracks of the uneven test disc and
verify that no sound skip or noise occurs.
envelope
Minimize the amplitude on make A=B.
5. Adjust the VR702 so that the section of the output of
the waveform
marked with x is balanced.
6. Disconnect the servo gain adjuster's leads from the
|
This section of the waveform must be balanced.
@ ALIGNMENT POINT
Please refer to Circuit Board and Wiring Connection Diagram for
test point locations.
TRACKING
TRACKING
GAIN
BALANCE
1¢701
VR705
TRACKING
[Vr7o2
[vares
ear
1c 702
VR706
(C705
~
OE
1c 707
[eran]
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