Sony icf 903 l service manual

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-“ 2 -“ mark mark - white/white only CF2 CF3 CF4 mark mark CF3 CF2 CF4 markCenter Frequency red 10.70 MHz blue 10.67 MHz orange 10.73 MHz black 10.64 MHz white 10.76 MHz white/white 10.75 MHz yellow 10.79 MHz HOW TO CHANGE THE CERAMIC FILTERS This model is used two ceramic filters of CF2, CF3 and CF4. You must use same type of color marked ceramic filters in order to meet same specifications. Therefore, the ceramic filter must change two pieces together since its supply two pieces in one package as a spare parts. 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. SAFETY-RELATED COMPONENT WARNING!! COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED LINE WITH MARK 0 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. TABLE OF CONTENTS 1. GENERAL Choosing Power Sources .............................................................. 3 Operating the Radio Manual Tuning ............................................ 3 2. DISASSEMBLY 2-1. Cabinet (Rear) ..................................................................... 4 2-2. Power Board ........................................................................ 4 2-3. Main Board, Key Board ...................................................... 5 2-4. Setting the Pointer ............................................................... 5 3. ELECTRICAL ADJUSTMENTS 3-1. MW section ......................................................................... 6 3-2. LW section .......................................................................... 6 3-3. SW section .......................................................................... 7 3-4. FM section ........................................................................... 7 4. DIAGRAMS 4-1. Block Diagram .................................................................... 9 4-2. Printed Wiring Boards (1/2) .............................................. 11 4-3. Printed Wiring Board (2/2) ................................................ 13 4-4. Schematic Diagrams .......................................................... 15 5. EXPLODED VIEWS 5-1. Cabinet (Front) Section ..................................................... 17 5-2. Cabinet (Rear) Section ...................................................... 18 6. ELECTRICAL PARTS LIST.................................... 19

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-“ 3 -“ SECTION 1 GENERAL This section is extracted from instruction manual.