Sony MDS-JE770 Focus Bias Check, C PLAY Check MO Error Rate Check, CD Error Rate Check

MDS-JE770

16.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the lAMS L 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 AEJECT 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

CN105 pin 4 (TE)		10pF
CN105 pin 6	(VC)

5-6-7. Focus Bias Check

Change the focus bias and check the focus tolerance amount.

Checking Procedure :

1.Load a continuously recorded test disc (MDW-74/GA-1). (Refer to “5-5. Using the Continuously Recorded Disc”.)

2.Rotate the l AMS L knob and display “CPLAY1 MODE”(C34).

3.Press the YES button and display “CPLAY1 MID”.

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

5.Rotate the lAMS L knob and display “FBIAS CHECK” (C16).

6.Press the YES button and display “ / c = ”.

The first four digits indicate the C error rate, the two digits after [/] indicate ADER, and the 2 digits after [c =] indicate the focus bias value.

Check that the C error is below 20 and ADER is below 2.

7.Press the YES button and display “ / b = ”. Check that the C error is below 100 and ADER is below 2.

8.Press the YES button and display “ / a = ”. Check that the C error is below 100 and ADER is below 2.

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

5-6-8. C PLAY Check

MO Error Rate Check

Checking Procedure :

1.Load a continuously recorded test disc (MDW-74/GA-1). (Refer to “5-5. Using the Continuously Recorded Disc”.)

2.Rotate the l AMS L knob and display “CPLAY1 MODE”(C34).

3.Press the YES button and display “CPLAY1 MID”.

4.The display changes to “C = AD = ”.

5.If the C error rate is below 20, check that ADER is 00.

6.Press the MENU/NO button, stop playback, press the AEJECT button, and test disc.

CD Error Rate Check

Checking Procedure :

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

2.Rotate the l AMS L knob and display “CPLAY1 MODE”(C34).

3.Press the YES button twice and display “CPLAY1 MID”.

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

5.Check that the C1 error rate is below 20.

6.Press the MENU/NO button, stop playback, press the AEJECT button, and the test disc.

5-6-9. 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 test disc (MDW-74/GA-1) into the unit.

2.Rotate the lAMS L knob to display “CREC1 MODE” (C34).

3.Press the YES button to display the “CREC1 MID”.

4.When recording starts, “ REC ” is displayed, this becomes “CREC 1 (@@@@)” (@@@@ is the address), and recording starts.

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

6.Rotate the lAMS L knob to display “C PLAY1 MODE” (C34).

7.Press the YES button to display “C PLAY1 MID”.

8.“C = AD = ” will be displayed.

9.Check that the C error becomes below 20 and the AD error below 2.

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

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