Introduction
This service manual provides comprehensive information for the ICOM IC-228A/E/H 144 MHz FM Transceiver. It covers the theoretical, physical, mechanical, and electrical characteristics necessary for servicing these models. The manual includes detailed specifications, block diagrams, circuit descriptions, disassembly and assembly procedures, maintenance and adjustment guidelines, board layouts, and parts lists.
For assistance or further information regarding the operation, capabilities, or servicing of the IC-228A/E/H, users are advised to contact their nearest authorized Icom Dealer or Icom Service Center.
Key Features and Specifications
- Models Covered: IC-228A, IC-228E, IC-228H
- Frequency Coverage: 144 MHz band (specific ranges vary by version)
- Mode: F3 (FM)
- Tuning Steps: Selectable (e.g., 5, 10, 12.5, 25 kHz)
- Power Output: Varies by model (e.g., 25W, 45W)
- Power Supply: 13.8 V DC
- Operating Temperature: -10°C to +60°C
Service Information
The manual details various circuit operations, including receiver circuits (RF, IF, Squelch, AF), transmitter circuits (Microphone Amplifier, Modulation, Drive Amplifier, Power Amplifier, APC), and PLL circuits. It also outlines essential repair notes, such as disconnecting power before opening covers and using insulated tuning tools for adjustments.
Detailed diagrams of the front panel, rear panel, main unit, and RX unit are provided for easy identification of components and connections.
For ordering replacement parts, ensure to include the equipment model and serial number, schematic part identifier, unit name, printed circuit board number, component part number and name, and the quantity required.
