21
HCD-GX8000/RG77
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
Procedure :
1. Connect an oscilloscope to TP (FEO).
2. Connect between TP (FEI) and TP (DVC) ( 1.65 V) by lead
wire.
3. Turn the power ON.
4. Load a disc (LUV-P01) and actuate the focus search. (In
consequence of open and close the disc tray, actuate the focus
search)
5. Confirm that the oscilloscope waveform (S-curve) is
symmetrical between A and B. And confirm peak to peak level
within 2
±
0.5 Vp-p.
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.
Procedure :
1. Connect an oscilloscope CH1 to TP (RFDC) and CH2 to TP
(RFAC).
2. Turn the power ON.
3. Load a disc (LUV-P01) and playback.
4. Confirm that oscilloscope waveform is clear and check if RF
signal level is correct or not.
BD board
Oscilloscope
TP(FEO)
TP(DVC)
symmetry
S-curve waveform
within 2
±
0.5Vp-p
A
B
oscilloscope
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) ADJUSTMENT
Procedure :
1. Connect an oscilloscope to TP (TEO) and TP (DVC).
2. Turn the power ON.
3. Load a disc (LUV-P01) and playback the number nine track.
4. Press the
hH
button. (Becomes the 1 track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscilloscope
waveform.
6. Adjust RV101 on the BD board so that the center of waveform
becomes the same voltage of DVC. (i.e. A=0V)
Connecting and Adjustment Location: BD board
RF signal waveform
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 0.65
±
0.15Vp-p (RFDC)
1.1
±
0.4Vp-p (RFAC)
TP(TEO)
TP(DVC)
BD board
oscilloscope
level=1.0
±
0.5Vp-p
symmetry
A (DC voltage)
center of
waveform
B
DVC
1 track jump waveform
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