3
D-CS901
SECTION 1
SERVICING NOTE
The laser diode in the optical pick-up block may suffer electrostatic
breakdown because of the potential difference generated by the
charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic breakdown 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.
BEFORE REPLACING THE OPTICAL PICK-UP BLOCK
Please be sure to check thoroughly the parameters as par the “Optical
Pick-Up Block Checking Procedures” (Part No.: 9-960-027-11)
issued separately before replacing the optical pick-up block.
Note and specifications required to check are given below.
• FOK output: IC601
yg
pin
When checking FOK, remove the lead wire to disc motor.
• RF signal P-to-P value: 0.4 to 0.65 Vp-p
LASER DIODE CHECK
During normal operation of the equipment, emission of the laser
diode is prohibited unless the upper lid is closed while turning ON
the S801. (push switch type)
The following checking method for the laser diode is operable.
• Method:
Emission of the laser diode is visually checked.
1. Open the upper lid.
2. Push the S801 as shown in Fig. 1.
3. Check the object lens for confirming normal emission of the
laser diode. If not emitting, there is a trouble in the automatic
power control circuit or the optical pick-up. During normal
operation, the laser diode is turned ON about 2.5 seconds for
focus searching.
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNIT
Fig. 1 Method to push the S801
S801