Sony MDS-PC3 M-crew Service Manual page 28

5-6-4. Auto Check
This test mode performs CREC and CPLAY automatically for
mainly checking the characteristics of the optical pick-up. To
perform this test mode, the laser power must first be checked.
Perform Auto Check after the laser power check and Iop compare.
Procedure
1. Press the @/1 button. If "LDPWR minicheck" is displayed, it
means that the laser power check has not been performed. In
this case, perform the laser power check and Iop compare, and
then repeat from step 1.
2. If a disc is in the mechanical deck, it will be ejected forcibly.
"DISC IN" will be displayed in this case. Load a test disc (MDW-
74/GA-1) which can be recorded.
3. If a disk is loaded at step 2, the check will start automatically.
4. When "XX CHECK" is displayed, the item corresponding to
XX will be performed.
When "06 CHECK" completes, the disc loaded at step 2 will be
ejected. "DISC IN" will be displayed. Load the check disc (MD)
TDYS-1.
5. When the disc is loaded, the check will automatically be resumed
from "07 CHECK".
6. After completing to test item 12, check OK or NG will be
displayed. If all items are OK, "CHECK ALL OK" will be
displayed. If any item is NG, it will be displayed as "NG:xxxx".
When "CHECK ALL OK" is displayed, it means that the optical
pick-up is normal. Check the operations of the other spindle motor,
thread motor, etc.
When displayed as "NG:xxxx", it means that the optical pick-up is
faulty. In this case, replace the optical pick-up.
5-6-5. Other Checks
All the following checks are performed by the Auto Check mode.
They therefore need not be performed in normal operation.
5-6-6. Traverse Check
5-6-7. Focus Bias Check
5-6-8. C PLAY Check
5-6-9. Self-Recording/Playback Check
5-6-6. Traverse Check
Connection :
BD board
CN105 pin 4 (TE)
CN105 pin 6 (VC)
Checking Procedure:
1. Connect an oscilloscope to CN105 pin 4 (TE) and CN105 pin
6 (VC) of the BD board.
2. Load a test disc (MDW-74/GA-1). (Refer to Note 1.)
3. Rotate the AMS knob and display "EF MO CHECK" (C14).
4. Press the @/1 button and display "EFB =
(Laser power READ power/Focus servo ON/tracking servo OFF/
spindle (S) servo ON)
28
5. Observe the waveform of the oscilloscope, and check that the
6. Press the @/1 button and display "EFB =
7. Observe the waveform of the oscilloscope, and check that the
8. Press the @/1 button display "EFB =
9. Observe the waveform of the oscilloscope, and check that the
Oscilloscope
V : 0.5 V/div
H : 10 ms/div
Input : DC mode
10. Press the @/1 button display "EF MO CHECK" (C14)
11. Press the x/Z "PGM" button and remove the disc.
12. Load the check disc (MD) TDYS-1.
MO-R".
13. Roteto the AMS knob and display "EF CD CHECK" (C15).
14. Press the @/1 button and display "EFB =
specified value is satisfied. Do not rotate the AMS knob.
(Read power traverse checking)
(Traverse Waveform)
VC
Specified value : Below 10% offset value
IA – BI
Offset value (%) = X 100
2 (A + B)
specified value is satisfied. Do not rotate the AMS knob.
(Write power traverse checking)
(Traverse Waveform)
VC
Specified value : Below 10% offset value
IA – BI
Offset value (%) = X 100
2 (A + B)
Then, the optical pick-up moves to the pit area automatically
and servo is imposed.
specified value is satisfied. Do not rotate the AMS knob.
(Traverse Waveform)
VC
Specified value : Below 10% offset value
IA – BI
Offset value (%) = X 100
2 (A + B)
The disc stops rotating automatically.
imposed automatically.
A
B
MO-W".
A
B
MO-P".
A
B
CD". Servo is