Sony HCD-XGV6 Service Manual page 21

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
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.
S-curve waveform
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
BD board
TP(RFDC)
TP(RFAC)
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.
Oscilloscope
symmetry
A
within 4 ± 1Vp-p
B
oscilloscope
HCD-XGV6/XGV8/XGV10AV
Note: Clear RF signal waveform means that the shape "◊" can be
clearly distinguished at the center of the waveform.
E-F Balance (1 Track jump) Check
oscilloscope
BD board
TP(TE)
TP(DVC)
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 oscilloscope
waveform.
0V
B=1.3 ± 0.6Vp-p
A
× 100=less than – 22%
Specified level:
B
Checking Location:
[BD BOARD]
SE
DVC
TE
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 1.45 ± 0.3Vp-p
center of
waveform
B
A (DC voltage)
symmetry
FE
RFDC
RFAC
DVC
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