Sony MDS-JE520 Stereo System User Manual


 
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0.9 mW power
Specified value : 0.84 to 0.92 mW
7.0 mW power
Specified value : 6.8 to 7.2 mW
lop (at 7mW)
Labeled on the optical pickup
Iop value ± 10mA
Traverse waveform
Specified value : Below 10% offset
Error rate check
Specified value : For points a, b, and c
C1 error : Below 220
AD error : Below 2
Error rate check
Specified value:
a.When using test disc (MDW-74/AU-1)
C1 error : Below 80
AD error : Below 2
b.When using check disc (TDYS-1)
C1 error : Below 50
CPLAY error rate check
Specified value:
C1 error : Below 80
AD error : Below 2
Unsatisfactory if displayed as T=@@ (##) [NG”
NG
(@@, ## are both arbitrary numbers)
CHECKS PRIOR TO PARTS REPLACEMENT AND ADJUSTMENTS
Before performing repairs, perform the following checks to determine the faulty locations up to a certain extent.
Details of the procedures are described in “5 Electrical Adjustments”.
Laser power check
(5-6-2 : See page 37)
Traverse check
(5-6-3 : See page 37)
Focus bias check
(5-6-4 : See page 38)
C PLAY check
(5-6-5 : See page 38)
Self-recording/playback
check
(REC/PLAY)
(5-6-6 : See page 38)
TEMP check
(Temperature
compensation
offset check)
(5-6-1 : See page 37)
Criteria for Determination
(Unsatisfactory if specified value is not satisfied)
Clean the optical pick-up
Adjust again
Replace the optical pick-up
Replace the optical pick-up
Replace the optical pick-up
Replace the optical pick-up
Replace the optical pick-up
If always unsatisfactory:
Replace the overwrite head
Check for disconnection of the circuits around the
overwrite head
If occasionally unsatisfactory:
Check if the overwrite head is distorted
Check the mechanism around the sled
Check for disconnection of the circuits around D101
(BD board)
Check the signals around IC101, IC121, CN102,
CN103 (BD board)
Measure if unsatisfactory:
Note:
The criteria for determination above is intended merely to determine if satisfactory or not, and does not serve as the specified value for
adjustments.
When performing adjustments, use the specified values for adjustments.
FORCED RESET
The system microprocessor can be reset in the following procedure.
Use these procedure when the unit cannot be operated normally due to the overrunning of the microprocessor, etc.
Procedure :
Disconnect the power plug, short-circuit jumper wire of JW800 and R451 (RESET).
[MAIN BOARD] (Component Side)
IC301
R451
JW800
Jumper wire
(RESET)
BT451