SECTION 5
ADJUSTMENTS
Focus Bias Check
CD SECTION
Condition :
Precautions for Adjustment
Y Hold the set in horizontal state.
1. Before beginning adjustment, set the equipment to service mode.
After the completion of adjustment, be sure to reset the service
Procedure :
mode.
For more information, see OService Mode (service program)�
[MAIN BOARD] (Side B)
on page 7.
2. Perform adjustments in the order given.oscilloscope
(AC range)
3. Use the disc (YEDS-18. Part No. 3-702-101-01) unless other-
wise indicated.IC501 @L pin
4. Power supply voltage requirement : DC 4.5 V2 kW(RF0)
HOLD switch : OFF
VOLUME: MinimumIC501 #1 pin
SOUND switch : NORM(VC)
AVLS switch: OFF
Before Beginning Adjustment
Set the equipment to service mode (See page 7) and check the fol-
lowing.
If there in an error, repair the equipment.
Y Checking of the sled motor
1. Open the upper panel.
23
2. Press the + and = keys and check that the optical pick-up
can move smoothly without sluggishness or abnormal noise in
innermost periphery n outermost periphery n innermost pe-
riphery.
+ : The optical pick-up moves outwardly
= : The optical pick-up moves inwardly
Y Checking of focus searching
1. Open the upper panel.
2. Press the ^ key. (Focus searching operation is activated con-
tinuously).
3. Check the object lens of the optical pick-up for smooth up/down
motion without sluggishness or abnormal noise.
4. Press the p key.
Check that focus searching operation is deactivated. If not, again
press the p key slightly longer.
1. Set the equipment to service mode stop state (See page 7).
2. Connect the oscilloscope between IC501 @L pin (RF0) and #1
pin (VC) on the MAIN board.
3. Move the optical pick-up by Pressing the + and = keys.
4 Put the disc (YEDS-18).
5. Press the ^ key.
From focus searching, focus is turned ON while entering
( )
CLV drawing-in mode. Tracking and sled are turned OFF.
6. Press the PLAY MODE key. (Both tracking and sled are turned
ON).
7. Check the oscilloscope waveform is as shown below.
A good eye pattern means that the diamond shape (a) in the cen-
ter of the waveform can be clearly distinguished.
RF level
0.8 � 1.2 Vp-p
Y RF Signal Reference Waveform (eye pattern)
To watch the eye pattern, set the oscilloscope to AC range and
increase the vertical sensitivity of the oscilloscope for easy watch-
ing.
8. Stop removing of the motor by pressing the p key.
9. After the completion of adjustment, reset service mode.
(See page 7 )
� 8 � |
ACEC
