Sony mce k 550 service manual

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Ñ 3 Ñ SECTION 1 SERVICING NOTE SELF-DIAGNOSIS This model has the self-diagnosis function for the video and audio decoder sections. Immediately after the power on, the self-diagnosis function searches each operation of ICÕs around the mechanism control microcomputer (IC504). The LED (D502) on the VIDEO board indicates their results. [VIDEO BOARD] Ñ SIDE A ÑHOW TO OPEN THE DISC TRAY WHEN POWER SWITCH TURNS OFF Insert a screwdriver into the aperture of the unit bottom, and turn in the direction of arrow (to OUT direction). *To close the disc table, turn the screwdriver in the reverse direction (to IN direction). 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 pick- up 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 Carry out the ÒS curve checkÓ in ÒCD section adjustmentÓ and check that the S curve waveform is output three times. LED (D101) INDICATION Light 1 Time blinking (Repeatedly) 2 Time blinking (Repeatedly) SYMPTOM No error Video decoder error (IC503) Video RAM error (IC502) Screwdriver IN OUT Pull out disc table. IC503 IC502IC504 D502 SL501SL503 SL502