Sony HCD-M80, Руководство по обслуживанию

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14
HCD-M80
SECTION 5
ELECTRICAL ADJUSTMENTS
– BD BOARD (Conductor Side) –
TP70
(TE)
TP68
(FE)
TP71
(RFDC)
TP73
(DVC)
TP72
(RFAC)
Note:
Clear RF signal waveform means that the shape “ ◊ ” can be clearly
distinguished at the center of the waveform.
TRAVERSE LEVEL CHECK
Procedure :
1. Connect an oscilloscope to TP70 (TE) and TP73 (DVC) on the
BD board.
2. Turn the power ON.
3. Load a disc (LUV-P01) and playback the number nine track.
4. Press the
CD N
button. (Becomes the 1 track jump mode.)
5. Confirm that the level B and A (DC voltage) on the oscillo-
scope waveform.
Connecting Location:
Note:
1. CD Block is basically designed to operate without adjustment. Therefore,
check each item in order given.
2. Use LUV-P01 (Part No. 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 TP68 (FE) and TP73 (DVC) on the
BD board.
2. Turn the power ON.
3. Load a disc (LUV-P01) and actuate the focus search. (In conse-
quence of open and close the disc tray, actuate the focus search)
4. 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.
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 an oscilloscope CH1 to TP71 (RFDC), CH2 to TP72
(RFAC) and TP73 (DVC) on the BD board.
2. Turn the power ON.
3. Load a disc (LUV-P01) and playback the number nine track.
4. Confirm that oscilloscope waveform is clear and check if RF
signal level is correct or not.
level=1.2
±
0.55Vp-p
symmetry
A (DC voltage)
center of
waveform
B
DVC
1 track jump waveform
TP70 (TE)
TP73 (DVC)
BD board
+
–
oscilloscope
RF signal waveform
VOLT/DIV : 200mV
TIME/DIV : 500ns
level : 0.75 ± 0.1Vp-p (RFDC)
1.05 ± 0.3Vp-p (RFAC)
+
–
oscilloscope
TP71 (RFDC)
TP72 (RFAC)
BD board
TP73 (DVC)
symmetry
S-curve waveform
within 2 ± 0.5Vp-p
A
B
+
–
oscilloscope
BD board
TP68 (FE)
TP73 (DVC)
CD SECTION