Adjustments - Sony Discman D-180AN Service Manual

CD SECTION
Precautions for Adjustment
1. Before beginning adjustment, set the equipment to service mode.
After the completion of adjustment, be sure to reset the service
mode.
For more information, see "Service Mode (service program)"
on page 7.
2. Perform adjustments in the order given.
3. Use the disc (YEDS-18. Part No. 3-702-101-01) unless other-
wise indicated.
4. Power supply voltage requirement : DC 4.5 V
HOLD switch
VOLUME
BASS BOOST switch
AVLS switch
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.
• Checking of the sled motor
1. Open the upper panel.
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 periph-
ery
+ : The optical pick-up moves outwardly
= : The optical pick-up moves inwardly
• 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.

ADJUSTMENTS

: OFF
: Minimum
: NORM
: OFF
SECTION 5
Focus Bias Check
Condition :
• Hold the set in horizontal state.
Procedure :
[MAIN BOARD] (Side B)
oscilloscope
(AC range)
IC501 #º pin
1. Set the equipment to service mode stop state (See page 7).
2. Connect the oscilloscope between IC501 @£ pin (RF0) and #º
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 (◊) in the cen-
ter of the waveform can be clearly distinguished.
• 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 –
IC501 @£ pin
2 k Ω
(RF0)
(VC)
IC501
30
23
RF level
1.0 ± 0.2V
)