ExpressLRS (ELRS) is an open-source RC link protocol known for ultra-low latency and long range. Two critical settings must match between transmitter module (TX) and receiver (RX): regulatory domain and bind phrase. Regulatory Domain: FCC vs LBT (ELRS/CE) ELRS firmware is compiled for a specific radio regulatory domain …

An ELRS link is really two protocols back to back: an RF air protocol between the handset's TX module and the receiver, and a CRSF serial protocol between the receiver and the flight controller. Setup (bind phrase, domain) lives in ELRS Configuration; the OSD numbers live in RC Telemetry. This snippet is the wire- and …