Sony MDM-7A, NEW, KMS-2608/J1N Auto Check, Other Checks, Traverse Check, Traverse Waveform

5-6-4. Auto Check

This test mode performs C-REC and C-PLAY automatically for mainly checking the characteristics of the optical pick-up. To perform this test mode, the laser power must first be checked. Perform Auto Check after the laser power check and Iop compare.

Procedure

1.Press the YES button. If “LDPWR minicheck” is displayed, it means that the laser power check has not been performed. In this case, perform the laser power check and Iop compare, and then repeat from step 1.

2.If a disc is in the mechanical deck, it will be ejected forcibly. “DISC IN” will be displayed in this case. Load a test disc (MDW- 74/GA-1) which can be recorded.

3.If a disk is loaded at step 2, the check will start automatically.

4.When “XX CHECK” is displayed, the item corresponding to

XX will be performed.

When “06 CHECK” completes, the disc loaded at step 2 will be ejected. “DISC IN” will be displayed. Load the check disc (MD) TDYS-1.

5.When the disc is loaded, the check will automatically be resumed from “07 CHECK”.

6.After completing to test item 12, check OK or NG will be displayed. If all items are OK, “CHECK ALL OK” will be displayed. If any item is NG, it will be displayed as “NG:xxxx”.

When “CHECK ALL OK” is displayed, it means that the optical pick-up is normal. Check the operations of the other spindle motor, thread motor, etc.

When displayed as “NG:xxxx”, it means that the optical pick-up is faulty. In this case, replace the optical pick-up.

5-6-5. Other Checks

All the following checks are performed by the Auto Check mode. They therefore need not be performed in normal operation.

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

5-6-6. Traverse Check

Connection :

Oscilloscope

BD board

CN105 pin 4 (TE)

CN105 pin 6 (VC)

V : 0.5 V/div

H : 10 ms/div

Input : DC mode

Checking Procedure:

1.Connect an oscilloscope to CN105 pin 4 (TE) and CN105 pin 6 (VC) of the BD board.

2.Load a test disc (MDW-74/GA-1). (Refer to Note 1.)

3.Press the M button and move the optical pick-up outside the pit.

4.Rotate the AMS knob and display “EF MO CHECK”.

5.Press the YES button and display “EFB = MO-R”.

(Laser power READ power/Focus servo ON/tracking servo OFF/ spindle (S) servo ON)

6.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob. (Read power traverse checking)

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

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

7.Press the YES button and display “EFB = MO-W”.

8.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not rotate the AMS knob. (Write power traverse checking)

(Traverse Waveform)

A

VC

B

Specified value : Below 10% offset value

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

9. Press the YES button display “EFB = MO-P”.

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

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 A 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.

24