ESPeidolon

License: MIT · source

ESPeidolon is amateur radio firmware that turns two inexpensive development boards into a bridge between a Bluetooth handheld radio — a Kenwood TH-D74 or TH-D75, or a UV-Pro — and everything else in the shack. One board, an ESP32 classic, speaks Bluetooth to the radio and re-exports the packet stream so phone and tablet APRS apps can use it; the second, an ESP32-S3, handles WiFi: a live web dashboard, a receive-only internet gateway for the Automatic Packet Reporting System (APRS), a network packet server, and a wired USB connection for anything expecting a traditional terminal node controller. Three jumper wires join the boards — the work is split in two to escape a single board's memory limits.

Everything travels as KISS, the simple serial protocol packet radio has used for decades, so existing apps connect without adapters or translation layers. If you know bb-link, this is the same idea with more features and a second board. Its own documentation is candid about the boundary: there is no modem inside — ESPeidolon is transport plumbing, and the radio does all the radio work.

As of version 0.9.1 the feature list runs deep: smart position beaconing with GPS, an APRS message inbox, firmware updates delivered over the air from one board to the other, LoRa hardware variants, a mesh-network client, a digipeater (a relay that repeats packets onward), a packet decoder, and a serial command line for setup and diagnostics. A single board running alone covers the Bluetooth-only case.

C++, built with PlatformIO. Code and documentation: github.com/leavesofgrass/espeidolon.