10.Rotate the AMS knob until the waveform of the oscilloscope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 2%. Adjust the waveform so that the specified value is satisfied as much as possible.
(Traverse Waveform)
A
VC
B
Specification A = B
11.Press the @/1 button, and save the adjustment results in the
Next “EF MO ADJUS (C07)” is displayed. The disc stops ro- tating automatically.
12.Press the x/Z “PGM” button and remove the disc.
13.Load the check disc (MD)
14.Roteto AMS knob and display “EF CD ADJUS” (C08).
15. Press the @/1 button and display “EFB = CD”. Servo is imposed automatically.
16.Rotate the AMS knob so that the waveform of the oscilloscope moves closer to the specified value.
In this adjustment, waveform varies at intervals of approx. 2%. Adjust the waveform so that the specified value is satisfied as much as possible.
(Traverse Waveform)
A
VC
B
Specification A = B
17. Press the @/1 button, display “EFB = SAVE” for a mo- ment and save the adjustment results in the
18.Press the x/Z “PGM” button and remove the check disc (MD)
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.
Oscilloscope
BD board | 330 kΩ |
CN105 pin 4 (TE) | 10pF | ||
CN105 pin 6 | (VC) | ||
|
5-13. FOCUS BIAS ADJUSTMENT
Adjusting Procedure :
1.Load a test disk
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 = | AD = )” is dis- |
played. |
|
5.Rotate the AMS knob and display “FBIAS ADJUST” (C09).
6.Press the @/1 button and display “ / a = T)”.
The first four digits indicate the C error rate, the two digits after
[/]indicate ADER, and the 2 digits after [a =] indicate the focus bias value.
7.Rotate the AMS knob in the clockwise direction and find the focus bias value at which the C error rate becomes 200 (Refer to Note 2).
8.Press the @/1 button and display “ / b = T”.
9.Rotate the AMS knob in the counterclockwise direction and find the focus bias value at which the C error rate becomes 200.
10.Press the @/1 button and display “ / c = T)”.
11.Check that the C error rate is below 20 and ADER is 00. Then
| press the | @/1 | button. |
|
|
|
| |
12. | If the “( | ” in “ - - |
| ( ” is above 20, press the | @/1 | |||
| button. |
|
|
|
|
|
|
|
| If below 20, press the |
| x/Z | button and repeat the | ||||
| adjustment from step 2. |
|
|
|
| |||
13. | Press the | x/Z “PGM” |
| button to remove the test disc. |
Note 1 : The relation between the C 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 C error rate changes, perform the adjustment using the average vale.
Cerror
200
b | c | a | Focus bias value |
|
|
| (F. BIAS) |
32