Sony MDS-NT1 service manual Focus Bias Adjustment, ENTER/YES button

7.Click the [ENTER/YES] and save the result of adjustment to the non-volatile memory (“EFB = SAVE” will be displayed for a moment. Then “EFB = MO-W” will be displayed).

8.Click the [JOG UP] or [JOG DOWN] so that the waveform of the oscilloscope becomes the specified value.

(When the [JOG UP] or [JOG DOWN] is clicked, the of “EFB= ” changes and the waveform changes.) In this ad- justment, waveform varies at intervals of approx. 2%. Adjust the waveform so that the specified value is satisfied as much as possible.

(Write power traverse adjustment)

Traverse Waveform

A

VC

B

Specification A = B

9.Click the [ENTER/YES], and save the adjustment results in the non-volatile memory. (“EFB = SAVE” will be displayed for a moment)

10.“EFB = MO-P” will be displayed.

The optical pick-up moves to the pit area automatically and servo is imposed.

11.Click the [JOG UP] or [JOG DOWN] 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

12.Click the [ENTER/YES], and save the adjustment results in the non-volatile memory. (“EFB = SAVE” will be displayed for a moment.)

Next “EF MO ADJUST” (C07) is displayed. The disc stops rotating automatically.

13.Click the [EJECT] and take out the disc.

14.Load the check disc (MD) TDYS-1.

15.Click the [JOG UP] or [JOG DOWN] to display “EF CD ADJUST” (C08).

16.Click the [ENTER/YES] to display “EFB = CD”. Servo is imposed automatically.

17.Click the [JOG UP] or [JOG DOWN] 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

MDS-NT1

18.Click the [ENTER/YES], display “EFB = SAVE” for a mo- ment and save the adjustment results in the non-volatile memory.

Next “EF CD ADJUST” (C08) will be displayed.

19.Click the [EJECT] button and take out the disc (MD) TDYS- 1.

Adjustment Location: BD board (see page 35)

5-14. FOCUS BIAS ADJUSTMENT

Adjusting Procedure:

1.Load the continuously-recorded disc. (Refer to “5. USING THE CONTINUOUSLY RECORDED DISC”)

2.Click the [JOG UP] or [JOG DOWN] to display “CPLAY2 MODE” (C36).

3.Click the [ENTER/YES] to display “CPLAY2MID”.

4.Click the [MENU/NO] when “C = AD = ” is displayed.

5.Click the [JOG UP] or [JOG DOWN] to display “FBIAS ADJUST” (C09).

6.Click the [ENTER/YES] to 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.Click the [JOG UP] and find the focus bias value at which the C1 error rate becomes about 200 (refer to Note 2).

8.Click the [ENTER/YES] to display “ / b = ”.

9.Click the [JOG DOWN] and find the focus bias value at which the C1 error rate becomes about 200.

10.Click the [ENTER/YES] to display “ / c = ”.

11.Check that the C1 error rate is below 20 and ADER is 00. Then click the [ENTER/YES].

12.If the “( )” in “ - - ( )” is above 20, click the

[ENTER/YES] button.

If below 20, click the [MENU/NO] and repeat the adjustment from step 2.

13.Click the [EJECT] button and take out the 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 auto- matically calculated from points A and B.

Note 2: As the C1 error rate changes, perform the adjustment using the average vale.

C1 error

about 200

Focus bias value

BCA

33