Cd Pick-Up Maintenance; How To Assemble/Remove Power Ic P.w.b - Sanyo DC-M3 Service Manual

CD PICK-UP MAINTENANCE

Pick-up (Optical lens) Cleaning
Clean the lens with the specified cleaning disc or moisten a cotton swab with isopropyl alcohol and cleaning paper.
Specified cleaning disc : LC-1 (Part code : 645 026 1961 ..... manufactured by SANYO.)
Regarding procedure of cleaning with moisten cotton swab, please refer to the attached as follows.
1. Cotton swab wrapped with Cleaning paper.
2. Add the isopropyl alcohol.
3. Gently move the tip of cotton swab just like a draw a whirlpool from inside to outside on the surface of lens.
CD ADJUSTMENTS
1. Confirm the tracking balance
1. Connect an Oscilloscope to TP2 (TE) and TP1 (VC).
2. Turn on the POWER switch.
3. Set the test disc. (DISC 1)
4. Press "STOP" button and "FM MODE" button simultaneously.
Within 1 second after pressing the "PLAY/PAUSE" button.
(SERVICE MODE : Tracking balance adjustment mode)
5. Confirm that the oscilloscope waveform is symmetrical on the
top and bottom in relation to 0V (VC).
2. Checking the "eye" pattern
1. Switch "ON" the POWER.
2. Connect an oscilloscope to TP4 (RF) and TP1 (VC).
3. Load the test disc.
4. Press the PLAY button.
5. Check to be sure that the "eye" pattern is at the center of
waveform and that the diamond shape is clearly defined.
6. Press the STOP button.
7. Turn off the POWER switch.

HOW TO ASSEMBLE/REMOVE POWER IC P.W.B

When assembling or removing power IC P.W.B, any stress should not be added on IC terminals.
At assembling : After connecting CN478 to CN470, fix heatsink
on the frame of power transformer with two
screws.
At removing : Remove two screw fixing heatsink and hold "A"
places as shown, then remove or connect socket.
200mV/div.
5ms/div.
TP4
(RF)
TP1
(VC)
Make sure that this socket is inserted to its end.
CN487
CN470
- 5 -
+
OSCILLOSCOPE
-
a
OPENING EXPANDED
A
Side View
b
A
Top View