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20
HCD-XGR88
CD SECTION
Note :
1. CD Block is basically designed to operate without adjustment.
Therefore, check each item in order given.
2. Use LUV-P01 (4-999-032-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10M 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
BD board
Oscilloscope
TP(FE)
TP(DVC)
Procedure :
1. Connect oscilloscope to TP (FE).
2. Connect between TP (FE) and TP (DVC ( 1.65 V) by lead
wire.
3. Press the
\/1
button to turn the power ON.
4. Load a disc (LUV-P01) and actuate the focus search. (In conse-
quence of open and close the disc tray, actuate the focus search)
5. Confirm that the oscilloscope waveform (S-curve) is symmetri-
cal between A and B. And confirm peak to peak level within 2
±
0.5 Vp-p.
symmetry
S-curve waveform
within 4
±
1Vp-p
A
B
6. After check, remove the lead wire connected in step 2.
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.
RF Level Check
TP(RFDC)
TP(RFAC)
BD board
oscilloscope
Procedure :
1. Connect oscilloscope to TP2 (RFDC) and TP1 (RFAC).
2. Press the
\/1
button to turn the power ON.
3. Load a disc (LUV-P01) and playback.
4. Confirm that oscilloscope waveform is clear and check RF
signal level is correct or not.
Note:
Clear RF signal waveform means that the shape “
◊
” can be
clearly distinguished at the center of the waveform.
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.45
±
0.3Vp-p
E-F Balance (1 Track jump) Check
TP(TE)
TP(DVC)
BD board
oscilloscope
Procedure:
1. Connect oscilloscope to TP (TE) and TP (DVC) board.
2. Press the
\/1
button to turn the power ON.
3. Load a disc (LUV-P01) and playback the number nine track.
4. Press the
bB
button. (Becomes the 1track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscillo-
scope waveform.
B=1.3
±
0.6Vp-p
symmetry
A (DC voltage)
center of
waveform
B
0V
Specified level:
×
100=less than – 22%
B
A
6. Adjust RV101 so that A (DC voltage) becomes 0.
Checking Location:
[BD BOARD]
DVC
RFAC
FE
SE
TE
RFDC
RV101
Summary of Contents for HCD-XGR88
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