Sony 4-216-349-5 Focus Bias Check, Play Checking MO Error Rate Check, CD Error Rate Check

10.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob.

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

Offset value (%) = IA – BI X 100 2 (A + B)

11.Press the YES button display “EF MO CHECK” The disc stops rotating automatically.

12.Press the § button and remove the disc.

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

14.Roteto the AMS knob and display “EF CD CHECK” (C04).

15. Press the	YES	button and display “EFB =	CD”. Servo is
imposed automatically.

16.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob.

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

Offset value (%) = IA – BI X 100 2 (A + B)

17.Press the YES button and display “EF CD CHECK”.

18.Press the § 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.

Oscilloscope

BD board 330 kΩ

CN110 pin 3 (TE)		10pF
CN110 pin 1	(VC)

5-6-4. Focus Bias Check

Change the focus bias and check the focus tolerance amount.

Checking Procedure :

1.Load a test disk (MDW-74/AU-1).

2.Rotate the AMS knob and display “CPLAY MODE”.

3.Press the YES button twice and display “CPLAY MID”.

4. Press the	MENU/NO	button when “C =	AD = ” is
displayed.

5.Rotate the AMS knob 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 220 and ADER is below 2.

7.Press the YES button and display “ / b = ”. Check that the C1 error is below 220 and ADER is below 2.

8.Press the YES button and display “ / a = ”. Check that the C1 error is below 220 and ADER is below 2.

9.Press the MENU/NO button, next press the § button, and remove the test disc.

5-6-5. C PLAY Checking

MO Error Rate Check

Checking Procedure :

1.Load a test disk (MDW-74/AU-1).

2.Rotate the AMS knob and display “CPLAY MODE”.

3.Press the YES button and display “CPLAY MID”.

4.The display changes to “C1 = AD = ”.

5.If the C1 error rate is below 80, check that ADER is below 2.

6.Press the MENU/NO button, stop playback, press the § but- ton, and test disc.

CD Error Rate Check

Checking Procedure :

1.Load a check disc (MD) TDYS-1.

2.Rotate the AMS knob and display “CPLAY MODE”.

3.Press the YES button twice and display “CPLAY MID”.

4.The display changes to “C1 = AD = ”.

5.Check that the C1 error rate is below 50.

6.Press the MENU/NO button, stop playback, press the § but- ton, and the test disc.

5-6-6. 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 disc (blank disc) into the unit.

2.Rotate the AMS knob to display “CREC MODE”.

3.Press the YES button to display the “CREC MID”.

4.When recording starts, “ REC ” is displayed, this becomes “CREC (@@@@)" (@@@@ is the address), and recording starts.

5.About 1 minute later, press the MENU/NO button to stop continuous recording.

6.Rotate the AMS knob to display “C PLAY MODE”.

7.Press the YES button to display “C PLAY MID”.

8.“C1 = AD = ” will be displayed.

9.Check that the C1 error becomes below 80 and the AD error below 2.

10.Press the MENU/NO button to stop playback, and press the § button and remove the disc.

– 22 –