Sony mdx c 7970 service manual

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Ð 2 Ð Notes on chip component replacement ¥ Never reuse a disconnected chip component. ¥ Notice that the minus side of a tantalum capacitor may be dam- aged by heat. Flexible Circuit Board Repairing ¥ Keep the temperature of the soldering iron around 270 ûC dur- ing 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. NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK OR BASE UNIT 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 PUB- LISHED BY SONY. CAUTION Use of controls or adjustments or performance of procedures other than those specified herein may result in hazardous ra- diation exposure. The laser diode in the optical pick-up block may suffer electro- static 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 Never look into the laser diode emission from right avove when checking it for adustment. It is feared that you will lose your sight. NOTES ON HANDLING THE OPTICAL PICK-UP BLOCK (KMS-241B/J1NP) The laser diode in the optical pick-up block may suffer electro- static break-down easily. When handling it, perform soldering bridge to the laser-tap on the flexible board. Also perform m easures against electrostatic break-down sufficiently before the operation. The flexible board is easily damaged and should be handled with care. laser-tap OPTICAL PICK-UP FLEXIBLE BOARD 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 COM- POSANTS QUE PAR DES PIéCES SONY DONT LES NUMƒROS SONT DONNƒS DANS CE MANUEL OU DANS LES SUPPLƒMENTS PUBLIƒS PAR SONY.

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Ð 3 Ð 1. GENERAL Location of Controls ....................................................... 4 Resetting the Unit ........................................................... 5 Detaching the Front Panel ............................................... 5 Preparing the Rotary Commander .................................. 5 Setting the Clock ............................................................. 5 Using the Rotary Commander ........................................ 5 Adjusting the Sound Characterisitics ............................. 5 Attenuating the Sound .................................................... 5 Changing the Sound and Display Settings ..................... 6 Boosting the Bass Sound ................................................ 6 Installation ....................................................................... 7 Connections ..................................................................... 8 2. DISASSEMBLY ......................................................... 12 3. ELECTRICAL ADJUSTMENTS Test Mode ........................................................................ 18 MD Section ..................................................................... 18 Tuner Section .................................................................. 18 4. DIAGRAMS 4-1. Block Diagram Ð SERVO Section Ð ............................... 23 4-2. Block Diagram Ð TUNER Section Ð .............................. 25 4-3. Block Diagram Ð MAIN Section Ð ................................. 27 4-4. Block Diagram Ð DISPLAY/KEY CONTROL Section Ð ........................ 29 4-5. Block Diagram Ð BUS CONTROL/POWER SUPPLY Section Ð ........... 31 4-6. Note for Printed Wiring Boards and Schematic Diagrams ....................................................... 33 4-7. Printed Wiring Boards Ð SERVO Section Ð ................... 35 4-8. Schematic Diagram Ð SERVO Board (1/3) Ð ................. 37 4-9. Schematic Diagram Ð SERVO Board (2/3) Ð ................. 39 4-10. Schematic Diagram Ð SERVO Board (3/3) Ð ................. 41 4-11. Printed Wiring Board Ð MAIN Board (Component Side) Ð .............................. 43 4-12. Printed Wiring Board Ð MAIN Board (Conductor Side) Ð ................................ 45 4-13. Schematic Diagram Ð MAIN Board (1/4) Ð ................... 47 4-14. Schematic Diagram Ð MAIN Board (2/4) Ð ................... 49 4-15. Schematic Diagram Ð MAIN Board (3/4) Ð ................... 51 4-16. Schematic Diagram Ð MAIN Board (4/4) Ð ................... 53 4-17. Printed Wiring Board Ð DISPLAY Board Ð ................... 55 4-18. Schematic Diagram Ð DISPLAY Board Ð ...................... 57 4-19. Printed Wiring Board Ð SUB Board Ð ............................ 59 4-20. Schematic Diagram Ð SUB Board Ð ............................... 61 4-21. IC Pin Function Description ........................................... 69 5. EXPLODED VIEWS ................................................ 79 6. ELECTRICAL PARTS LIST ............................... 83 TABLE OF CONTENTS