However, the digital age and a passionate community of modders have breathed new life into this classic rig. The right can transform this marine radio into a modern, versatile, high-performance ham transceiver. This guide explores the most valuable, safe, and effective modifications to boost frequency coverage, audio quality, and usability.
. This involves modifying the RAM board that stores channel data; since the CPU constantly reads from this SRAM during power-on, external microcontrollers or larger SRAM chips can be interfaced to cycle through multiple memory banks. Split Mode Modification
By opening up the frequency limits and tweaking the audio characteristics of the Icom IC-M700, you can breathe new life into an iconic piece of maritime history, gaining a rugged, bulletproof HF transceiver that outperforms many modern plastic radios in sheer durability. If you plan to proceed with these upgrades, let me know: icom m700 mods
The transmit restrictions are controlled by a diode matrix located on the (often shielded under a metal cover near the front panel assembly).
If you want to proceed with a specific upgrade, let me know: However, the digital age and a passionate community
Ensure jumper W37 (marked "W1037") is installed. If it is cut, solder it back together to enable all-frequency transmission.
The is a legendary marine HF transceiver prized by radio amateurs for its rugged 150W PA and reliable performance. While built for the high seas, several modifications can transform it into a capable "shack" radio for ham operations. Essential Frequency & Transmit Mods If you plan to proceed with these upgrades,
The factory M700 audio is heavily compressed and filtered to cut through marine atmospheric noise. While great for emergencies at sea, it can sound harsh or restricted on Ham radio bands. Microphone Gain and Compression Tuning
For the M700TY variant, power adjustment is accomplished via a potentiometer on the main board. is the critical component—a variable resistor that controls output power. Turning clockwise increases power output while counterclockwise decreases it. The factory default is 150 watts. By rotating R244 clockwise approximately 15–20 degrees, maximum output can be increased to around 210 watts, with current draw increasing from approximately 22A to 28A.
The IC-M700's native 48-channel limit is a significant bottleneck for modern amateur use. SRAM Expansion