FreeTX

Open source radio control system for almost anything.
Remotely operate model airplanes, multicopters, helicopters, boats, land vehicles, robots, animatronics, etc.

Main features

20 fully proportional RC channels, each encoded with 10 bits.
Configurable RC channel output signal format.
Update rate of 50x per second for all RC channels.
Receiver binding, adjustable RF power, frequency hopping.
Reverse, subtrim, endpoints, failsafe.
Dual rates and expo, custom curves, flight modes.
Powerful mixer system, logical switches, function generators, counters, timers.
Telemetry, alarms, warnings, notifications, home screen widgets.
Custom splash screen, screenshot capture, etc.
Model memory. I2C eeprom and SD card supported.
Model types, context-aware nomenclature.
Intuitive user interface.

Hardware and Schematics

The transmiter and receiver schematics can be found in the 'schematics' folder. The major components are

1x Atmega2560 microcontroller, 2x Atmega328p microcontrollers.
2x SX1276/77/78/79 or RFM95 based Lora modules. Other RF modules can possibly be used with some modifications to the source code.
128x64 KS0108 based LCD. Any 128x64 LCD can however be used (provide own driver code).