Sony HCD-MJ1, Service Manual

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6-8. Focus Bias Adjustment
Adjusting Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Continuously Recorded Disc”.)
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. Press the NO button when “C1 = AD = ” is displayed.
5. Rotate the JOG dial and display “FBIAS ADJUST”.
6. Press the YES button and display “ / a = ”.
The first four digits indicate the C1 error rate, the two digits after
[/] indicate ADER, and the 2 digits after [a =] indicate the focus
bias value.
7. Rotate the JOG dial in the clockwise direction and find the focus
bias value at which the C1 error rate becomes 220.
8. Press the YES button and display “ / b = ”.
9. Rotate the JOG dial in the counterclockwise direction and find
the focus bias value at which the C1 error rate becomes 220.
10.Press the YES button and display “ / c = ”.
11.Check that the C1 error rate is below 50 and ADER is 00.
Then press the YES button.
12.If the “( )” in “ - - ( )” is above 20, press the YES
button.
If below 20, press the NO button and repeat the adjustment from
step 2 again.
13.Press the NO button and press the MD
§
button to remove the
continuously recorded disc.
Note 1 : The relation between the C1 error and focus bias is as shown
in the following figure. Find points a and b in the following
figure using the above adjustment. The focal point position
c is automatically calculated from points a and b.
Note 2 :
As the C1 error rate changes, perform the adjustment using
the average vale.
C1 error
220
Focus bias value
(F, BIAS)
b c b
6-9. Error Rate Check
6-9-1. CD Error Rate Check
Checking Method :
1. Load a test disc TDYS-1.
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. “C1 = AD = - -” is displayed.
5. Check that the C1 error is below 20.
6. Press the NO button, stop playback, press the MD
§
button, and
remove the test disc.
6-9-2. MO Error Rate Check
Checking Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Continuously Recorded Disc”.)
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. “C1 = AD = ”is displayed
5. If the C1 error rate is below 50, check that ADER is 00.
6. Press the NO button, stop playback, press the MD
§
button, and
remove the continuously recorded disc.
6-10. Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Method :
1. Load a continuously recorded disc (Refer to “6-4. Creating MO
Continuously Recorded Disc”.)
2. Rotate the JOG dial and display “CPLAY MODE”.
3. Press the YES button twice and display “CPLAY MID”.
4. Press the NO button when “C1 = AD = ” is displayed
5. Rotate the JOG dial and display “FBIAS CHECK”.
6. Press the YES button and display “ / c = ”.
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 50 and ADER is 00.
7. Press the YES button and display “ / b = ”.
Check that the C1 error is not below 220 and ADER is not above
00 every time.
8. Press the YES button and display “ / a = ”.
Check that the C1 error is not below 220 and ADER is not above
00 every time.
9. Press the NO button, next press the MD
§
button, and remove the
continuously recorded disc.
Note 1 :
If the C1 error and ADER are above 00 at points a or b, the
focus bias adjustment may not have been carried out prop-
erly. Adjust perform the beginning again.