Icom IC-M88 MAIN UNIT

	• BOTTOM VIEW	The combination of this page and previous page shows
	• BOTTOM VIEW	the unit layout in the same configuration as the actual
		the unit layout in the same configuration as the actual
		P.C. Board.

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Contents

Page INTRODUCTION DANGER ORDERING PARTS REPAIR NOTES TABLE OF CONTENTS SECTION 1 SPECIFICATIONS VHF MARINE CHANNEL LIST WX CHANNEL LIST SECTION 2 INSIDE VIEWS • LOGIC UNIT • MAIN UNIT SECTION 3 DISASSEMBLY INSTRUCTIONS SECTION 4 CIRCUIT DESCRIPTION 4-1RECEIVER CIRCUITS 4-2TRANSMITTER CIRCUITS 4-3PLL CIRCUIT (MAIN UNIT) 4-4POWER SUPPLY CIRCUITS 4-5PORT ALLOCATIONS CPU–Continued 4-5-2EXPANDER IC (MAIN UNIT; IC341) 4-5-3D/A CONVERTOR IC (MAIN UNIT; IC251) SECTION 5 ADJUSTMENT PROCEDURES 5-1PREPARATION • CONNECTION CAUTION: • SCREEN EXAMPLE NOTE: 5-2SOFTWARE ADJUSTMENT • MAIN UNIT TOP VIEW SOFTWARE ADJUSTMENT – continued SECTION PARTS LIST [CHASIS UNIT] [MAIN UNIT] Page Page SECTION 7 MECHANICAL PARTS AND DISASSEMBLY VR UNIT LOGIC UNIT MAIN UNIT CHARGER UNIT SECTION 8 SEMIPARTS-CONDUCTORLISTINFORMATION 8 - 1 TRANSISTORS AND FETs • MAIN unit and LOGIC unit • CHARGER unit 8 - 2 DIODES SECTION 9 BOARD LAYOUTS 9 - 1 CHARGER UNIT (BC-152) 9-2VR UNIT 9-3CONNECTOR UNIT 9-4MAIN UNIT MAIN UNIT 9-5LOGIC UNIT LOGIC UNIT SECTION 10 BLOCK DIAGRAM VR UNIT SECTION 11 VOLTAGE DIAGRAM