Sony CDP CX240 Service Manual

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Ð 2 Ð CAUTIONUse of controls or adjustments or performance of procedures other than those specified herein may result in hazardous ra- diation exposure. Notes on chip component replacement ¥ Never reuse a disconnected chip component. ¥ Notice that the minus side of a tantalum capacitor may be damaged by heat. Flexible Circuit Board Repairing ¥ Keep the temperature of soldering iron around 270ûC during repairing. ¥ Do not touch the soldering iron on the same conductor of the circuit board (within 3 times). ¥ Be careful not to apply force on the conductor when soldering or unsoldering. Laser component in this product is capable of emitting radiation exceeding the limit for Class 1. This appliance is classified as a CLASS 1 LASER product. The CLASS 1 LASER PROD- UCT MARKING is located on the rear exterior. The following caution label is located inside of the unit. PARTS No. MODEL MODEL IDENTIFICATION Ñ BACK PANEL Ñ 4-999-020-0¹ 4-999-020-1¹ US Canadian SAFETY-RELATED COMPONENT WARNING !! COMPONENTS IDENTIFIED BY MARK ! OR DOTTED LINE WITH MARK ! ON THE SCHEMATIC DIAGRAMS AND IN THE PARTS LIST ARE CRITICAL TO SAFE OPERATION. REPLACE THESE COMPONENTS WITH SONY PARTS WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY. ATTENTION AU COMPOSANT AYANT RAPPORT Ë LA SƒCURITƒ!! LES COMPOSANTS IDENTIFIƒS PAR UNE MARQUE ! SUR LES DIAGRAMMES SCHƒMATIQUES ET LA LISTE DES PIéCES SONT CRITIQUES POUR LA SƒCURITƒ DE FONCTIONNEMENT. NE REMPLACER CES COMPOSANTS QUE PAR DES PIéCES SONY DONT LES NUMƒROS SONT DONNƒS DANS CE MANUEL OU DANS LES SUPPLƒMENTS PUBLIƒS PAR SONY. SAFETY CHECK-OUT After correcting the original service problem, perform the follow- ing safety checks before releasing the set to the customer: Check the antenna terminals, metal trim, ÒmetallizedÓ knobs, screws, and all other exposed metal parts for AC leakage. Check leakage as described below. LEAKAGE The AC leakage from any exposed metal part to earth Ground and from all exposed metal parts to any exposed metal part having a return to chassis, must not exceed 0.5 mA (500 microampers). Leak- age current can be measured by any one of three methods. 1. A commercial leakage tester, such as the Simpson 229 or RCA WT-540A. Follow the manufacturersÕ instructions to use these instruments. 2. A battery-operated AC milliammeter. The Data Precision 245 digital multimeter is suitable for this job. 3. Measuring the voltage drop across a resistor by means of a VOM or battery-operated AC voltmeter. The ÒlimitÓ indication is 0.75 V, so analog meters must have an accurate low-voltage scale. The Simpson 250 and Sanwa SH-63Trd are examples of a pas- sive VOM that is suitable. Nearly all battery operated digital multimeters that have a 2V AC range are suitable. (See Fig. A) Fig. A. Using an AC voltmeter to check AC leakage . PART NO. 0.15 µF To Exposed Metal Parts on Set 1.5k W AC voltmeter (0.75V) Earth Ground

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Ð 3 Ð TABLE OF CONTENTS 1. SERVICING NOTE .......................................................... 3 2. GENERAL .......................................................................... 6 3. DISASSEMBLY 3-1. Front Panel Assembly ........................................................... 7 3-2. Back Panel Assembly ............................................................ 7 3-3. Base (Door, Gear) Assembly ................................................ 8 3-4. Table Assembly ..................................................................... 8 3-5. Mechanism Deck .................................................................. 9 3-6. Base Unit ............................................................................. 9 4. TEST MODE ..................................................................... 10 5. ADJUSTMENTS 5-1. Mechanical Adjustment ...................................................... 13 5-2. Electrical Block Checking .................................................. 19 6. DIAGRAMS 6-1. Circuit Boards Location ...................................................... 22 6-2. Block Diagrams ¥ BD Section ........................................................................ 23 ¥ Main Section ..................................................................... 25 6-3. Schematic Diagram Ð BD Section Ð ................................... 29 6-4. Printed Wiring Board Ð BD Section Ð ................................. 31 6-5. Printed Wiring Board Ð Main Section Ð .............................. 33 6-6. Schematic Diagram Ð Main (1/2) Section Ð ........................ 35 6-7. Schematic Diagram Ð Jack Section Ð .................................. 37 6-8. Printed Wiring Board Ð Jack Section Ð ............................... 39 6-9. Schematic Diagram Ð Display Section Ð ............................ 41 6-10. Printed Wiring Board Ð Display Section Ð ........................ 43 6-11. Schematic Diagram Ð Sensor/Motor Section Ð ................. 45 6-12. Printed Wiring Board Ð Sensor/Motor Section Ð .............. 46 6-13. IC Block Diagrams ............................................................ 47 6-14. IC Pin Functions ................................................................ 49 7. EXPLODED VIEWS 7-1. Case and Back Panel Section .............................................. 54 7-2. Disc Table Section .............................................................. 55 7-3. Front Panel Section ............................................................. 56 7-4. Mechanism Section-1 (CDM-40B) ..................................... 57 7-5. Mechanism Section-2 (CDM-40B) ..................................... 58 7-6. Mechanism Section-3 (CDM-40B) ..................................... 59 7-7. Base Unit Section (KSM-213BKN/M-N) ........................... 60 8. ELECTRICAL PARTS LIST ........................................ 61 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, ob- serve from more than 30 cm away from the objective lens. The emission check enables continuous checking of the S curve. 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.

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Ð 20 Ð Disc Sensor Adjustment Perform this adjustment after completing all adjustments of the mechanism section. If not performed accurately, the presence of the disc may not be detected properly. Connection 1: Waveform 1: Connection 2: Waveform 2Procedure: 1. Connect the oscilloscope to Pins 1, 2, and 4 of CN506 of the MAIN board. Also connect a 1 kW resistor to Pin 4 at the same time. (Connection 1) 2. Check that no discs are loaded in the unit. 3. With the power OFF, press the 1/u button while pressing the INPUT button, and turn on the power at the same time. 4. The rotary table will continue rotating in the clockwise direction. 5. Observe the waveform at that time on the oscilloscope. 6. Loosen the screw securing the LUMINOUS board slightly. 7. Slide the LUMINOUS board to the left and right so that the peak of the D0 waveform is at the center between the descending point of the T1 wavefor m and ascending point of the T2 waveform. (Waveform 1) After adjusting, apply locking compound. 8. Disconnect the resistor connected to Pin 4 of CN506 of the MAIN board. (Connection 2) 9. Observe the waveform on the oscilloscope. (Waveform 2) 10. Adjust RV501 of the MAIN board so that the waveform on the oscilloscope satisfies the following adjustment value 1. 11. Press the 1/u button and turn OFF the power. 12. Press the 1/u button, turn on the power, press the OPEN/ CLOSE button, and open the front cover. Next rotate the DISC/ CHARACTER dial in the counterclockwise direction continuously so that the rotary table rotates continuously in the counterclockwise direction. 13. Observe the waveform on the oscilloscope and confirm that it satisfies the adjustment value 2 (waveform 3). If it does not, adjust RV501 of the MAIN board. Waveform 3: CN506 of MAIN board T1 : Pin 1 (TS. 1) T2 : Pin 2 (TS. 2) D0 : Pin 4 (D. SENS)oscilloscop e 1 kW AB T1 T2 D 0 CN506 of MAIN board T1 : Pin 1 (TS. 1) T2 : Pin 2 (TS. 2) D1 : Pin 4 (D. SENS)oscilloscope XZ Y T1 T2 D1 LUMINOUS boar d XZ Y T1 T2 D1