Building and setup

ExpressLRS (ELRS) explained

ExpressLRS (ELRS) is the open-source radio system that provides the control link between your radio and drone — fast, sensitive and affordable. In the Netherlands, you will usually use the 2.4GHz version. Bind it with a binding phrase (a word entered in both your radio and receiver) or with the manual three-cycle method. Remember: ELRS is the control link, not your video feed or flight controller.

What is ELRS?

ExpressLRS is an open-source radio protocol: Express (extremely fast) and Long Range (highly sensitive). It sends your stick movements to the drone and telemetry back to the radio. Packet rates reach up to 1000 Hz, and distances of more than 100 km have been achieved with 2.4GHz hardware. Being open source also makes it cheaper than most alternatives.

An important distinction: ELRS is only the control link. Your video feed uses a separate VTX, and you configure the drone with Betaflight.

Which frequency should you use in the Netherlands?

ELRS uses two bands: 2.4GHz (by far the most common) and 868/900MHz for extra range. In the Netherlands, choose the EU version for your band; it complies with the European Listen-Before-Talk requirements. The band is fixed in the firmware, so your transmitter and receiver must use the same one.

Transmitter and receiver

On the transmitter side, ELRS is either built into your radio or added as a separate external module. On the drone, you need a receiver, either separate or pre-installed on a bind-and-fly drone. The radio itself runs EdgeTX. Looking for one? Browse our radios.

Binding: two methods

Binding phrase (recommended) — enter the same phrase in both your radio and receiver (at least 8 characters, such as your pilot name). They will then bind to each other automatically. It is not a password or encryption, but it prevents you from accidentally binding to someone else’s drone.

Manual three-cycle binding — with the radio off, quickly power the receiver on and off 3 times (leaving it on for about 2 seconds each time) until the LED double-blinks: that is binding mode. Then turn on your radio and select [Bind] in the ELRS menu. When the LED remains solid, it is bound.

Since ELRS v3.4.0, a receiver with a binding phrase can re-enter binding mode through three power cycles, bind_rx in Betaflight, or a 1.5-second press of the receiver button.

Flashing firmware

Use ExpressLRS Configurator to build and flash firmware for both your transmitter and receiver. There are three methods: Wi-Fi (connect to the receiver’s access point at 10.0.0.1), UART (USB cable) or EdgeTX passthrough. Use the same settings on both: band and binding phrase.

ELRS is under active development — check expresslrs.org for the latest firmware and Configurator before flashing.

Common problems

Will not bind — on firmware older than 3.4, a configured binding phrase blocks the three-cycle method. Use the same phrase or update; from 3.4 onward, three power cycles, bind_rx, and a 1.5-second button press also work with a phrase.
LED status — a slow blink means waiting for a connection, a double blink is binding mode, and a triple blink indicates Model Match. Solid with the transmitter on normally means connected; if it stays solid with the transmitter off, check for bootloader mode and wiring problems.
Telemetry works, but controls do not — model mismatch: enable Model Matching so the radio and receiver use the same model.

Frequently asked questions

What is ExpressLRS?

An open-source radio system that provides the control link between your radio and drone. It is fast, sensitive and affordable. It is not your video feed or Betaflight.

Which ELRS frequency should I use in the Netherlands?

Usually 2.4GHz; 868/900MHz is an option for extra range. Choose the EU version for your band — it complies with the European Listen-Before-Talk requirements. Transmitter and receiver must use the same band.

What is a binding phrase?

A phrase (at least 8 characters) entered in both your radio and receiver so they bind to each other automatically. It is not encryption, but prevents you from binding to the wrong drone.

My ELRS will not bind — what should I do?

First confirm that the transmitter and receiver use the same band, major version and binding phrase. On firmware older than 3.4, a phrase can block the three-cycle method; from 3.4 onward, you can also use three power cycles, bind_rx or a 1.5-second receiver-button press.

Does ELRS work with Betaflight?

Yes. In Betaflight, set the receiver protocol to CRSF — the protocol used by ELRS. See the Betaflight guide.

Last reviewed on August 17, 2026.

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