D-EJ119/EJ120/EJ121
SECTION 1
SERVICING NOTE
TEST MODE
NOTES ON HANDLING THE OPTICAL PICK-UP
The software version display and LCD test can be performed when
BLOCK OR BASE UNIT
the test mode is activated.
The laser diode in the optical pick-up block may suffer electrostatic
Procedure:
breakdown because of the potential difference generated by the
1. Confirm the set is not powered on. (Remove two batteries and
charged electrostatic load, etc. on clothing and the human body.
disconnect the AC power adaptor.)
During repair, pay attention to electrostatic breakdown and also use
2. Short the solder land SL801 (TEST) on the MAIN board.
the procedure in the printed matter which is included in the repair
3. Turn on the main power. (Insert two batteries.)
parts.
4. Microcomputer version is displayed for about a second.
The flexible board is easily damaged and should be handled with
5. After that all segments of the liquid crystal display are turned
care.
on.
6. Turn off the main power. (Remove two batteries.)
NOTES ON LASER DIODE EMISSION CHECK
7. Open the solder land SL801 (TEST) on the MAIN board.
The laser beam on this model is concentrated so as to be focused on
Note : The solder should be removed clean.
the disc reflective surface by the objective lens in the optical pick-
up block. Therefore, when checking the laser diode emission,
MAIN BOARD (SIDE B)
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 OOptical
Pick-Up Block Checking Procedures� (Part No.: 9-960-027-11)
issued separately before replacing the optical pick-up block.
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
LASER DIODE AND FOCUS SEARCH OPERATION
CHECK
During normal operation of the equipment, emission of the laser
diode is prohibited unless the upper lid is closed while turning ON
the S809. (push switch type)
The following checking method for the laser diode is operable.IC801
Y Method:
Emission of the laser diode is visually checked.
SL801
1. Open the upper lid.(TEST)
2. With a disc not set, turn on the S809 with a screwdriver having a
thin tip as shown in Fig.1.
3. Press the u button.
4. Observing the objective lens, check that the laser diode emits
light.
When the laser diode does not emit light, automatic power control
circuit or optical pickup is faulty.
In this operation, the objective lens will move up and down 4
times along with inward motion for the focus search.
lever(lid detection)
lever(lid detection)
S809
MAIN board
Fig. 1 Method to push the S809
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ACEC
