Radio control systems can be expensive and confusing with their various incompatible protocols (FHSS, DSSS, and so on), but Malcolm Messiter “simplified” the whole paradox by just making their own Teensy-powered transmitter and receiver from scratch.
The transmitter uses a Teensy 4.1, and the receiver a 4.0, both equipped with a Nordic nRF24L01+ 2.4GHz transceiver, providing a range of approximately 2.5km! The current firmware supports 16 channels, 12-bit servo resolution, four flight modes, 32 mixes, 99 model memories with import and export, FHSS (Frequency Hopping Spread Spectrum), PWN and SBUS output, failsafe on any channel, digital trims and graphic curves on all channels, and user-defined channel names. All of this is managed via a GUI on a Nextion color touch screen. Binding is via a 64-bit ID for maximum security. These features dramatically exceed the specs of many high-end radio systems costing hundreds, or even thousands of dollars, and are demonstrated effortlessly controlling an SAB Urukay in the video below.