Cd Section - Sony HCD-CPX11 Service Manual

CD SECTION

Note:
1. CD Block is basically constructed to operate without
adjustment.
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicated.
3. Use an oscilloscope with more than 10 MW 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.
5. Check the focus bias check when optical pick -up block is
replaced.
FOCUS BIAS CHECK
BD81A board
TP (RFAC)
TP (VC)
Procedure :
1. Connect oscilloscope to TP (RFAC) and TP (VC) on the
BD81A board.
2. Press the ?/1 button to turn the power ON, and press the Z
(CD) button to open the CD disc tray.
3. Set disc (YEDS-18) on the tray and press the
to playback.
4. Confirm that oscilloscope waveform is as shown in the figure
below. (eye pattern)
A good eye pattern means that the diamond shape ( ◊ ) in the
center of the waveform can be clearly distinguished.
oscilloscope
(DC range)
+
–
NX button
CD
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
level:
0.9 ± 0.4 Vp-p
Checking Location:
– BD81A BOARD (Side B) –
IC251
TP
(VC)
(RFAC)
HCD-CPX11
IC301
IC101
TP
25