EXPRESS LRS
The modern radio link. Packet rates, telemetry ratios, and full MAVLink integration via the Backpack ecosystem.
High Performance Link
Advanced Modes: F, D, and K
[ELRS](/field-manual/build-guide/radio-control-link.html) is not static. It supports multiple modulation modes tailored for different environments....
ArduPilot Integration: Setup & Params
Integrating [ELRS](/field-manual/build-guide/radio-control-link.html) with ArduPilot is straightforward, but optimizing it for [MAVLink](/field-man...
ELRS Foundations: LoRa & CSS Physics
ExpressLRS (ELRS) represents a paradigm shift from traditional FSK (Frequency Shift Keying) radios. It utilizes **LoRa (Long Range)** modulation, a...
Link Symmetry & TX-as-RX
Standard [ELRS](/field-manual/build-guide/radio-control-link.html) systems are **Asymmetric**. The Transmitter (Ground) has 1000mW of power. The Re...
MAVLink over ELRS: The 'Airport' Bridge
Traditionally, Long Range pilots needed two radios: Crossfire for Control, and SiK [Radio](/field-manual/mavlink-interface/radio.html) (900MHz) for...
Packet Rates, Latency & Range
One size does not fit all. ExpressLRS forces you to choose your **Packet Rate** (Update Frequency). This choice defines the fundamental capabilitie...
Telemetry Ratios & Bandwidth Math
Unlike traditional radios with fixed telemetry, [ELRS](/field-manual/build-guide/radio-control-link.html) allows you to tune the **Uplink/Downlink ...
The Backpack Architecture: Wi-Fi & ESP8285
The "Backpack" is a secondary processor (ESP8285) inside your [ELRS](/field-manual/build-guide/radio-control-link.html) Transmitter module. It acts...
The Yaapu Problem & The HUD Solution
For years, ArduPilot users have relied on the **Yaapu Telemetry Script** to see flight data on their [radio](/field-manual/mavlink-interface/radio....