3
SECTION 1
SERVICING NOTES
The laser diode in the optical pick-up block may suffer electrostatic
break-down because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic break-down and also
use the procedure in the printed matter which is included in the
repair parts.
The flexible board is easily damaged and should be handled with
care.
NOTES ON LASER DIODE EMISSION CHECK
The laser beam on this model is concentrated so as to be focused on
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission,
observe from more than 30 cm away from the objective lens.
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
Carry out the “S curve check” in “CD section adjustment” and check
that the S curve waveform is output repeatedly.
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
HOW TO OPEN THE DISC TRAY WHEN POWER SWITCH
TURNS OFF
Insert a tapeing driver into the aperture of the unit bottom, and turn
in the direction of arrow (to OUT direction).
* To close the disc table, turn the driver in the reverse direction
(to IN direction).
SELF-DIAGNOSIS
This unit is equipped with a self-diagnosis function.
The function is used for diagnosing the conditions of the circuits of
the VIDEO board.
The circuits can be determined if normal or abnormal by the lighting
of D502 on the VIDEO board.
Lighting of D502
When lit
: Operates normally
Blinks repeatedly : The circuit may be faulty.
[VIDEO Board] (Side B)
table
tapering driver
D502
IC505
The following extension cable is required to check and adjust the
VIDEO board.
J-2501-155-A
CN601/MAIN
↔
CN451/VIDEO
J-2501-156-A
CN906/MAIN
↔
CN453/VIDEO
J-2501-157-A
CN101/BD
↔
CN501/VIDEO
* To close the disc table, turn the tapering
driver in the reverse direction (to IN direction).