Introduction
This service manual contains the latest information for the ICOM IC-T7A/E Dual Band FM Transceiver. It is designed to assist technicians with the maintenance and repair of the device. The manual details specifications, internal views, disassembly instructions, circuit descriptions, adjustment procedures, and parts lists for various models and versions of the transceiver.
Safety precautions are emphasized, including warnings against connecting to power sources exceeding 16V, exposing the unit to liquids, or applying excessive RF signals to the antenna connector, as these actions can cause irreparable damage.
Key Features and Specifications
The IC-T7A/E operates on the 144 MHz and 430 (440) MHz bands, with frequency coverage varying by region (USA, Europe, SE Asia, Italy, Australia). Key specifications include FM modulation, frequency stability, various tuning steps, BNC antenna connector, and external DC power requirements. The transceiver offers RF output power of 4.0 W for VHF and 3.0 W for UHF at 13.5 V DC.
Service Information
The manual provides detailed circuit descriptions for receiver and transmitter functions, including duplexer circuits, RF amplifiers, mixers, IF circuits, and power amplifier stages. It also covers PLL circuits, power supply configurations, and other essential circuits like tone squelch. Comprehensive adjustment procedures for PLL and transmitter functions are included, along with port allocations for the CPU.
Parts and Disassembly
Instructions for disassembling the transceiver are provided, including steps for removing panels, the 2F unit, the LOGIC unit, and the 1F unit. A detailed parts list and information on mechanical parts and semiconductors are also available to aid in component replacement.
