Sony HCD-GTX66 Service Manual page 29

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3. Mode: Playback
test tape
P-4-A100
(10 kHz, –10 dB)
L-CH
MAIN
board
CN510
R-CH
in phase 45 °
4. After the adjustments, apply suitable locking compound to
the pats adjusted.
Adjustment Location: Playback Head (Deck A).
TE
L 13942296513
forward
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oscilloscope
pin 1
pin 2
L
V H
R
pin 3
waveform of oscilloscope
90 ° 135 ° 180 °
good wrong
Record/Playback/Erase Head (Deck B).
reverse
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CD SECTION
[TEST DISC LIST]
Use the following test disc on test mode.
• CD: YEDS-18 (PART No. 3-702-101-01)
PATD-012 (PART No. 4-225-203-01)
Note:
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use YEDS-18 (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10MW impedance.
4. Clean the object lens by an applicator with neutral detergent
when the signal level is low than specified value with the
following checks.
[S-CURVE CHECK]
BD91 board
TP106(FE)
TP124(VC)
Procedure :
1. Connect an oscilloscope to TP106 (FE) and TP124 (VC).
2. Turn the power on.
3. Load a disc (YEDS-18) and actuate the focus search. (In
Q Q
consequence of open and close the disc tray, actuate the focus
3 6 7 1 3 1 5
search)
4. Confirm that the oscilloscope waveform (S-curve) is
symmetrical between A and B. And confirm peak to peak level
within 3 ± 0.5 Vp-p.
S-curve waveform
Note: • Try to measure several times to make sure than the ratio
of A : B or B : A is more than 10 : 7.
• Take sweep time as long as possible and light up the
brightness to obtain best waveform.
co
.
HCD-GTX66/GTX77
9 4 2 8
or
oscilloscope
+
–
0 5 8 2 9 9 4 2 8
symmetry
A
within 3 ± 0.5Vp-p
B
m
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