Scott Dylewski built Analog Redial, an open-source hardware project that gives old landline phones a functional second life. The system runs on an ESP32-C6 paired with an ES8388 audio codec and supports two simultaneous analog phone connections, dial tone, ringing, SIP server integration, and a built-in answering machine.
The project is worth reading in full for its implementation details. Dylewski wired in Home Assistant control via dial codes, exposed a web interface for configuration, and added an optional Bluetooth board so a rotary or touchtone handset can operate as a modern smartphone headset. All design files are on GitHub at sdylewski/Analog-Redial, and the board can be ordered pre-assembled from a board house.
This is not a novelty demo. It is a documented, reproducible telephone exchange you can build yourself. The combination of SIP support, home automation hooks, and Bluetooth bridging in a two-line ESP32 design makes it a serious starting point for anyone doing telephony work at home.
[READ ORIGINAL →]