SECTION 1
SERVICING NOTES
NOTES ON LASER DIODE EMISSION CHECK
NOTES ON HANDLING THE OPTICAL PICK-UP
The laser beam on this model is concentrated so as to be focused
BLOCK OR BASE UNIT
on the disc reflective surface by the objective lens in the optical
The laser diode in the optical pick-up block may sufpick-up blocfer electro-k. Therefore, when checking the laser diode emis-
static breakdown because of the potential differsion, observe from more than 30 cm away from the objective lens.ence generated by
the charged electrostatic load, etc. on clothing and the human body.
During repair, pay attention to electrostatic breakdoLaser Diode Checwn and alsoking Methods
use the procedure in the printed matter which is included in theDuring normal operation of the equipment, emission of the laser
repair parts.diode is prohibited unless the upper panel is closed while turning
The flexible board is easily damaged and should be handled withON the S809 (push switch type).
care.The following two checking methods for the laser diode are oper-
able.
Befor Replacing the Optical Pick-Up Block
Please be sure to check thoroughly the parameters as par the OOp-Y Method (In the service mode or normal operation):
tical Pick-Up Block Checking Procedures� (Part No.: 9-960-027-Emission of the laser diode is visually checked.
11) issued separately before replacing the optical pic1. Open the upper lid.k-up block.
Note and specifications required to check are gi2.ven beloPush the S809 as shown in Fig. 1.w.
3. Press the ^ key.
Y FOK output: IC501 !a pin4. Check the object lens for confirming normal emission of the
When checking FOK, remov the lead wire to disc motorlaser diode. If not emitting, there is a trouble in the automatic.
Y S curve P-to-P value: 2.5 #�Vp-p IC501 pinpower control circuit or the optical pick-up.
When checking S curve P-to-P value, remove the lead wire toDuring normal operation, the laser diode is turned ON about
disc motor.10 seconds for focus searching.
Y RF signal P-to-P value: 0.8 - 1.2 Vp-p
Y Traverse signal P-to-P value: 1 - 2.6 Vp-p
Y The repairing grating holder is impossible.
Y Adjusted part for tracking gain adjustment: RV504
S809
Fig. 1 Method to push the S809
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ACEC
