SONY DNE520
Manual de Servicio

D-NE520
Ver. 1.4

SECTION 1 SERVICING NOTES

NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT 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 pickup 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 During normal operation of the equipment, emission of the laser diode is prohibited unless the upper lid is closed while turning ON the S501. (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. With a disc not set, turn on the S501 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, detector

NOTES ON HANDLING OF PATCH The handling of PATCH is necessary when a mounted EGL board is exchanged or when EEPROM(IC1602) on an EGL board is exchanged. Please confirm in each service front office about the infomation on the handling of PATCH.

S501

JACK BOARD

lever, detector

Fig. 1 Method to push the S501

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