Sony MDS-JA333ES Service Manual page 9

[Checks before Part Replacement and Adjustment]

Cause of faulty can be approximately located by performing the following checks before starting the repair work. Refer to Section "5.

Electrical Adjustment" the check procedure.

Laser power check

(Refer to section 5-6-2.)

Traverse check

(Refer to section 5-6-3.)

Focus bias check

(Refer to section 5-6-4.)

C PLAY check

(Refer to section 5-6-5.)

Self record/playback check

(Refer to section 5-6-6.)

Temperature compensation

offset check

(Refer to section 5-6-1.)

Note: The judgment criterion is shown for the purpose of judging if the performance is acceptable or not. This is not the specification value for adjustment.

Use the specification value for adjustment when the MDS-JA333ES is going to be adjusted.

Judgment criterion(NG when the measurement

value is out of the specification value)

• 0.9 mW power

Specification value: 0.8 to 0.96 mW

• 6.2 mW power

Specification value: 6.0 to 6.4 mW

• Iop (when 7 mW)

The Iop value that is shown on the optical

pick-up: +/- 4 mA

• Traverse waveform

Specification value: Offset 5% or less

• Checking the error rate

Specification value: All points of a and b

CI error 220 or less

AD error 2 or less

• Checking the error rate

Specification value:

a. When using the test disc (MDW-74/AU-1)

CI error 50 or less

AD error 2 or less

b. When using the check disc (TDYS-1)

CI error 20 or less

• Checking the error rate in C PLAY

Specification value:

CI error 50 or less

AD error 2 or less

• NG when "T=@@(##)(NG" appears

(@@ and ## are arbitrary numbers.)

Remedial measure in case of NG

• Cleaning the optical pick-up

• Readjustment

• Replacing the optical pick-up

• Replacing the optical pick-up

• Replacing the optical pick-up

• Replacing the optical pick-up

• Replacing the optical pick-up

In case of NG all the time:

• Replacing the overwrite head

• Check disconnection of the circuits around

the overwrite head

In case of intermittent NG:

• Check deformation of overwrite head

• Check mechanism around the sled

• Check disconnection of the circuits around

the D101 (BD board)

• Check signals around the IC101, IC121,

CN102 and CN103 (BD board)

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