SONY LBT-N455K
Manual de Servicio

SECTION 1 SERVICING NOTE
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 repain 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 �S curve check� in �CD section adjustment� and check that the S curve waveform is output three times. FL Display Tube, LED All Lit and Key Check mode When the TUNER/BAND , DISPLAY/DEMO , and FILE 2 buttons are pressed simultaneously, the FL display tube and LEDs will all light up. Press any button to enter the key check mode. When the key check mode is entered, the FL display tube displays �K 1 J0 V0�. Each time a button is pressed, the counter increases in the following order, K 2 n K 3 n K 4. If buttons already pressed once are pressed again, the counter will not increase. When the VOLUME knob is rotated in the + direction, the count increases in the following order. V1 n V2 n V3. When rotated in the � direction, it decreases in the following order. V0 n V9 n V8. When the AMS dial is rotated in the clockwise direction, the count increases in the following order. J1 n J2 n J3. When rotated in the counterclockwise direction, it decreases in the following order. J0 n J9 n J8. To exit form the test mode, press the TUNER/BAND , DISPLAY/ DEMO , FILE 2 buttons simultaneously again. Switching the channel step 9 kHz/10 kHz Press ENTER/NEXT button and SYSTEM POWER button simultaneously to switch the AM channel step 9 kHz and 10 kHz. Be sure not to change with carelessness. All Reset When TUNER/BAND , DISPLAY/DEMO , and FILE3 buttons are pressed simultaneously, the contents of a preset are restored to those at shipping.

SECTION 2 GENERAL

This section is extracted from instruction manual.

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