Sony HCD-C5 service manual Auto Check, Other Checks, Traverse Check

HCD-C5

6-4. Auto Check

This test mode performs CREC and CPLAY 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 .“R” or >“R” button to display “AUTO CHECK” (C01).

2.Press the ENTER/YES “R” button. If “LDPWR ” 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 enter the MD test mode.

3.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.

4.If a disc is loaded at step 3, the check will start automatically.

5.When “XX CHECK” is displayed, the item corresponding to XX will be performed.

When “06 CHECK” completes, the disc loaded at step 3 will be ejected. “DISC IN” will be displayed. Load the check disc (TDYS-1).

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

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

When “CHK ALL OK” is displayed, it means that the optical pick- up is normal. Check the operations of other parts (spindle motor, sled motor, etc.).

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

6-5. Other Checks

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

6-6. Traverse Check

6-7. Focus Bias Check

6-8. C PLAY Check

6-9. Self-Recording/Playback Check

6-6. Traverse Check

Note 1: Data will be erased during MO reading if a recorded disc is used in this adjustment.

Note 2: If the traverse waveform is not clear, connect the oscilloscope as shown in the following figure so that it can be seen more clearly.

oscilloscope (DC range)

BD (MD) board	330 k Ω
CN105 pin 4 (TE)	+
CN105 pin 6 (VC)	–
	10 pF

Connection:

oscilloscope (DC range)

BD (MD) board

CN105 pin 4 (TE)	+	V: 0.1 V/div
CN105 pin 6 (VC)	–
		H: 10 ms/div

Procedure:

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

2.Load a disc (any available on the market). (Refer to Note 1)

3.Press the M “R” button to move the optical pick-up outside the pit.

4.Press the . “R” or > “R” button to display “EF MO CHECK”(C14).

5.Press the ENTER/YES “R” button to 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 press the . “R” or

>“R” button.

(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 ENTER/YES “R” button to display “EFB = MO- W”.

8.Observe the waveform of the oscilloscope, and check that the specified value is satisfied. Do not press the . “R” or

>“R” button. (Write power traverse checking)

Traverse Waveform

A

VC

B

Specified value : Below 10% offset value

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

38