D-EJ785
SECTION 1
SERVICING NOTES
ABOUT CD-Rs/CD-RWsLASER DIODE AND FOCUS SEARCH OPERATION
? This CD player can play CD-Rs/CD-RWs recorded in the Com-CHECK
pact Disc Digital Audio (Audio CD) format, but playback capa-During normal operation of the equipment, emission of the laser
bility may vary depending on the quality of the disc and thediode is prohibited unless the upper lid is closed while turning ON
condition of the recording device.the S801. (push switch type)
The following checking method for the laser diode is operable.
NOTES ON HANDLING THE OPTICAL PICK-UP
BLOCK OR BASE UNITY Method:
Emission of the laser diode is visually checked.
The laser diode in the optical pick-up block may suffer electro-1. Open the upper lid.
static breakdown because of the potential difference generated by2. With a disc not set, turn on the S801 with a screwdriver having
the charged electrostatic load, etc. on clothing and the human body.a thin tip as shown in Fig.1.
During repair, pay attention to electrostatic breakdown and also3. Press theB X key.
use the procedure in the printed matter which is included in the4. Observing the objective lens, check that the laser diode emits
repair parts.light.
The flexible board is easily damaged and should be handled withWhen the laser diode does not emit light, automatic power
care.control circuit or optical pickup is faulty.
In this operation, the objective lens will move up and down 5
NOTES ON LASER DIODE EMISSION CHECKtimes along with inward motion for the focus search.
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 emis-detection lever
sion, 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 OOp-
tical 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.
Y FOK output: IC601 yg pin
When checking FOK, remove the lead wire to disc motor.
Y RF signal P-to-P value: 0.45 to 0.65 Vp-p
detection lever
S801
MAIN board
Fig. 1 Method to push the S801
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ACEC
