RF Level Check
CD SECTION
CD DECODERoscilloscope
board
Note:
1. CD Block is basically constructed to operate without adjustment.
Therefore, check each item in order given.
TP (RF)
2. Use YEDS-18 disc (3-702-101-01) unless otherwise indicatedCN12 (VC).
3. Use an oscilloscope with more than 10MW impedance.
4. Clean the object lens by an applicator with neutral deterProcedure :gent
when the signal level is low than specified value with the f1. Connect oscilloscope to test point ol-TP (RF) on CD DECODER
lowing checks.board.
5. Adjust the focus bias adjustment when optical block is replaced.2. Turned Power switch on.
3. Put disc (YEDS-18) in and playback.
Focus Bias Adjustment4. Confirm that oscilloscope waveform is clear and check RF sig-
nal level is correct or not.
Note:Clear RF signal waveform means that the shape Oa� can be
DC voltmeter
clearly distinguished at the center of the waveform.
CD DECODER
board
CN12VOLT/DIV: 200 mV
FEO+TIME/DIV: 500 nS
VC�
+0.3
level: 1.0 Vp-p
�0.2
Procedure:
1. Connect DC voltmeter to test point CN12 (FEO), (VC) on CD
DECODER board.
2. Turned Power switch on.Adjustment Location:CD DECODER board
3. Put disc (YEDS-18) in and stop.
4. Adjust VR01 so that the DC voitmeter reading is 0 ? 20 mV.
Adjustment Location:CD DECODER board
Focus Gain Adjustment (VR02)
This gain has a margin, so even if it is slightly off.
There is no problem.
Therfore, do not perform this adjusment.
Please note that it should be fixed to mechanical center position
when you moved and do not know original position.
Adjustment Location
[CD DECODER BOARD] N Component side N
CN12
IC03
VC
FEO
RF Level
IC01
VR01
Focus Bias
R07
VR02
Focus Gain
N 13 N |
ACEC
SONY
