Open-source ESP32 + SA818 module PCB turns any Android 8+ phone into a 1W VHF/UHF ham transceiver with APRS, GPS, and no separate battery.
Key Takeaways
Hardware stack: custom PCB (order from PCBWay/JLCPCB), SA818-V/U or DRA818V/U radio module, SMA antenna, ESP32 firmware, USB-C connection to phone.
Full APRS support including 1200 baud modem for SMS-like messaging plus position beaconing, which most dedicated handhelds omit.
GPL3 covers everything: Android app, ESP32 firmware, PCB designs, and 3D printer case files.
Requires Technician class amateur radio license minimum; kits available pre-soldered and pre-flashed.
Accessibility features built in: live closed captions, sticky PTT with haptic feedback, animation controls.
Hacker News Comment Review
Range ceiling for 1W VHF is roughly 10 km handheld-to-handheld due to line-of-sight physics; repeaters are the practical fix, not antenna swaps.
Commenters note the 1W output compares poorly to a cheap Baofeng at 8W, though the phone-integration and APRS software stack differentiate it.
Friction points raised: no PDF schematic export forces KiCAD just to read the design, and no clear product photos on the main project page.
Notable Comments
@thenthenthen: Notes shanzhai Android phones with built-in PTT radios have existed for a decade but manufacturers refused to open the software stack despite licensed hacker requests.
