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20
HCD-XGV50
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
Ω
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
Procedure :
1. Connect oscilloscope to TP (RFDC) and TP (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
Checking Location:
[BD BOARD] (SIDE B)
DVC
RFDC
RFAC
TE
FE
SE
DVC
TP(RFDC)
TP(RFAC)
BD board
oscilloscope
Summary of Contents for HCD-XGV50
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