20
HCD-CPX1
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 M
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.
5.
Check the focus bias check when optical pick -up block is
replaced.
FOCUS BIAS CHECK
Procedure :
1.
Connect oscilloscope to TP (RFAC) and TP (VC) on the BD
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
CD
NX
button
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.
s
Checking Location:
+
–
BD board
TP (RFAC)
TP (VC)
oscilloscope
(DC range)
VOLT/DIV: 200 mV
TIME/DIV: 500 ns
level:
0.9
±
0.4 Vp-p
TP
(RFAC)
TP
(VC)
– BD BOARD (Conductor Side) –
IC103
IC102
IC101
