UHF FM Transceivers | Icom IC-F21S instruction

SERVICE MANUAL

UHF FM TRANSCEIVERS

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Icom IC-F21S service manual UHF FM Transceivers

Contents

UHF FM Transceivers Ordering Parts IntroductionRepair Notes Table of Contents ‘ General Specifications‘ Transmitter ‘ Receiver Main Unit TOP View Inside ViewsBottom View Removing the Chassis Disassembly InstructionsRemoving the Main Unit Receiver Circuits Circuit Description Transmitter Circuits General PLL CircuitVCO Circuit PLL Circuit Port Allocations Power Supply Circuits Voltage LinePin Port Description Number 3 D/A Convertor IC IC9 Output Expander IC IC15 Preparation Adjustment Procedures JIG cable Screen display exampeSPE GND DC Power Supply GND DC power cable connectionsConnection PLL Lock PLL AdjustmentMain Voltage Software Adjustment Squelch SensitivityLevel SQL Unit Section Parts ListMain Unit Coil Eljfc R68M-F Array Electrolytic ECEV1CA470SP Connector Accessories Mechanical Parts and DisassemblyChassis Parts Screw abbreviations B0, BT Self-tapping IC-F21S Transistor and FET’S SEMI-CONDUCTOR InformationDiodes Main Unit Board Layouts IC6 FT1 TOP View SW-A Unit SW-A and SW-B UnitsSW-B Unit CBI0 CBI1 CBI2 CBI3 Bottom View SW-A UnitGND Tled Rled VCC Volin Volout Disassembly Information Parts ListBC-146 Optional Desktop Charger Information Charge Unit Board Layout Voltage Diagram SW-A/SW-B Unit S1 Block Diagram 2SC4215 O Voltage Diagram DTC144EU Section Voltage Diagram Q1 XP4216 SW-A UnitPage 32, Kamiminami, Hirano-ku, Osaka, 547-0003, Japan