📡 ELRS (ExpressLRS)
A popular open-source long-range, low-latency RC link protocol — an affordable, community-developed alternative to proprietary long-range systems.
What it actually does
ExpressLRS is an open-source radio link that became popular very quickly because it delivers long range and very low latency on inexpensive hardware. It is now the default choice across much of the FPV world and is increasingly used on surface models too.
In practice
It runs on 2.4GHz or 900MHz, with 900MHz trading packet rate for penetration and range. Packet rate is user-selectable — higher rates give lower latency for racing, lower rates give more range. Being open source, firmware updates arrive often and transmitter and receiver must be kept on matching versions.
Worth knowing
Both ends must run compatible firmware and share a binding phrase. Updating one half and not the other is the usual reason a previously working link stops binding.