Sony MDS-DRE1 Service Manual page 18

Focus Bias Adjustment
Adjusting Method:
1. Load a continuously recorded disc (Refer to "Page 15 Creat-
ing Continuously Recorded Disc").
[AMS]
2. Rotate the knob and display "CPLAY MODE".
[ENTER/YES]
3. Press the
MID".
[EDIT/NO]
4. Press the button when "C1 =
displayed.
[AMS]
5. Rotate the knob and display "FBIAS ADJUS".
[ENTER/YES]
6. Press the button and display "
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.
[AMS]
7. Rotate the knob in the clockwise direction and find the
focus bias value at which the C1 error rate becomes about 200
(Refer to Note 2) .
[ENTER/YES]
8. Press the button and display "
[AMS]
9. Rotate the knob in the counterclockwise direction and
find the focus bias value at which the C1 error rate becomes
about 200.
The C1 error rate at this time should be almost same as the
value set in step 7.
[ENTER/YES]
10. Press the button and display "
11. Check that the C1 error rate is below 50 and ADER is 00.
[ENTER/YES]
Then press the
12. If the "( " in " -
[ENTER/YES]
button.
[EDIT/NO]
If below 20, press the
ment from step 2 again.
[EDIT/NO]
13. Press the button and press the
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 value.
C1 error
about 200
b
button twice and display "CPLAY
AD =
/ a =
/ b =
/ c =
button.
- ( " is above 20, press the
button and repeat the adjust-
[ EJECT]
button
§
Focus bias
value
(F. BIAS)
c a
Error Rate Check
CD Error Rate Check
Checking Method:
1. Load a check disc (MD) TDYS-1.
[AMS]
2. Rotate the
[ENTER/YES]
3. Press the
MID".
" is 4. "C1 = AD =
5. Check that the C1 error rate is below 20.
[EDIT/NO]
6. Press the
". button, and remove the check disc.
MO Error Rate Check
Checking Method:
1. Load a continuously recorded disc (Refer to "Page 15 Creat-
ing Continuously Recorded Disc").
[AMS]
". 2. Rotate the
[ENTER/YES]
3. Press the
MID".
4. "C1 = AD =
5. If the C1 error rate is below 50, check that ADER is 00.
[EDIT/NO]
6. Press the
". button, and remove the continuously recorded disc.
Focus Bias Check
Change the focus bias and check the focus tolerance amount.
Checking Method:
1. Load a continuously recorded disc (Refer to "Page 15 Creat-
ing Continuously Recorded Disc").
[AMS]
2. Rotate the
[ENTER/YES]
3. Press the
MID".
[EDIT/NO]
4. Press the
displayed.
[AMS]
5. Rotate the
[ENTER/YES]
6. Press the
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.
[ENTER/YES]
7. Press the
Check that the C1 error is not below about 200 and ADER is
not above 00 every time.
[ENTER/YES]
8. Press the
Check that the C1 error is not below about 200 and ADER is
not above 00 every time.
[EDIT/NO]
9. Press the
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 properly. Adjust
perform the beginning again.
– 18 –
knob and display "CPLAY MODE".
button twice and display "CPLAY
" is displayed.
button, stop playback, press the
knob and display "CPLAY MODE".
button twice and display "CPLAY
" is displayed.
button, stop playback, press the
knob and display "CPLAY MODE".
button twice and display "CPLAY
button when "C1 =
knob and display "FBIAS CHECK".
button and display "
button and display "
button and display "
[ EJECT]
button, next press the
§
[ EJECT]
§
[ EJECT]
§
AD = " is
/ c = ".
/ b = ".
/ a = ".
button,