This GitHub repository contains the development of an APRS hub that transmits various sensor data like spO2, location, and altitude. The project uses Raspberry Pi, Tiny Circuit Python boards, and MQTT for data transmission.
An open-source device, kv4p HT, connects to an Android smartphone and turns it into a radio transceiver for about $35. It uses an ESP32 and transmits one watt, featuring APRS and scanning capabilities. The PCB is simple and affordable with a 3D-printed case.
