Sony MDS-PC3 M-crew Service Manual page 29

15. Observe the waveform of the oscilloscope, and check that the
specified value is satisfied. Do not rotate the AMS knob.
(Traverse Waveform)
VC
Specified value : Below 10% offset value
IA – BI
Offset value (%) =
2 (A + B)
16. Press the @/1 button and display "EF CD CHECK" (C15).
17. Press the x/Z "PGM" button and remove the check disc
(MD) TDYS-1.
Note 1 : MO reading data will be erased during if a recorded disc is
used in this adjustment.
Note 2 : If the traverse waveform is not clear, connect the oscillo-
scope as shown in the following figure so that it can be
seen more clearly.
BD board
CN105 pin 4 (TE)
CN105 pin 6 (VC)
5-6-7. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).
(Refer to "5-5. Using the Continuously Recorded Disc".)
2. Rotate the AMS knob and display "CPLAY1MODE" (C34).
3. Press the @/1 button and display "CPLAY1 MID".
4. Press the x/Z button when "C =
played.
5. Rotate the AMS knob and display "FBIAS CHECK" (C16).
6. Press the @/1 button and display "
The first four digits indicate the C1 error rate, the two digits
after [/] indicate ADER, and the 2 digits after [c =] indicate the
focus bias value.
Check that the C1 error is below 20 and ADER is below 2.
7. Press the @/1 button and display "
Check that the C1 error is below 100 and ADER is below 2.
8. Press the @/1 button and display "
Check that the C1 error is below 100 and ADER is below 2.
9. Press the x/Z button, next press the A button, and remove
the test disc.
X 100
Oscilloscope
330 kΩ
10pF
AD = )" is dis-
/ c = )".
/ b = )".
/ a = )".
5-6-8. C PLAY Check
MO Error Rate Check
Checking Procedure :
1. Load a continuously recorded test disc (MDW-74/GA-1).
(Refer to "5-5. Using the Continuously Recorded Disc".)
A
2. Rotate the AMS knob and display "CPLAY1MODE" (C34).
3. Press the @/1 button and display "CPLAY1 MID".
4. The display changes to "C =
B
5. If the C1 error rate is below 20, check that ADER is 00.
6. Press the x/Z button, stop playback, press the x/Z "PGM"
button, and test disc.
CD Error Rate Check
Checking Procedure :
1. Load a check disc (MD) TDYS-1.
2. Rotate the AMS knob and display "CPLAY1MODE" (C34).
3. Press the @/1 button twice and display "CPLAY1 MID".
4. The display changes to "C =
5. Check that the C1 error rate is below 20.
6. Press the x/Z button, stop playback, press the x/Z "PGM"
button, and the test disc.
5-6-9. Self-Recording/playback Check
Prepare a continuous recording disc using the unit to be repaired
and check the error rate.
Checking Procedure :
1. Insert a recordable test disc (MDW-74/GA-1) into the unit.
2. Rotate the AMS knob to display "CREC 1MODE" (C35).
3. Press the @/1 button to display the "CREC1 MID".
4. When recording starts, "
"CREC1 (@@@@)" (@@@@ is the address), and recording
starts.
5. About 1 minute later, press the x/Z button to stop
continuous recording.
6. Rotate the AMS knob to display "CPLAY 1MODE" (C34).
7. Press the @/1 button to display "CPLAY1 MID".
8. "C = AD =
9. Check that the C1 error becomes below 20 and the AD error
below 2.
10. Press the x/Z button to stop playback, and press the x/Z
"PGM" button and remove the disc.
AD = )".
AD = )".
REC " is displayed, this becomes
)" will be displayed.
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