~40×20 mm (e.g., similar to a CP2102 breakout)
The Icom CI-V system is a serial communication protocol used to control Icom radios. It uses a simple two-wire interface (Data and Ground) that operates at TTL logic levels (5V). icom ci v usb interface schematic top
If you want, I can:
For a reliable "top-tier" homebrew design, using a dedicated USB-to-TTL serial chip like the is highly recommended. ICOM CI-V - K7MEM ~40×20 mm (e