RadioMaster XR4 Gemini Xrossband Dual-Band ExpressLRS Receiver

RadioMaster XR4 ELRS Receiver User Manual Product Description:The XR4 Receiver is a next-generation, true diversity dual-band ExpressLRS receiver, engineered for maximum reliability, range, and responsiveness. Featuring dual Semtech LR1121 RF transceivers, it supports both 2.4GHz and 900MHz Sub-G frequencies and leverages the ExpressLRS Gemini Xrossband (Gem-X) protocol for unmatched RF performance. With two fully independent RF circuits and dual T-type antennas, the XR4 provides exceptional reception sensitivity, superior link stability, and versatile operation—whether in single-frequency Gemini mode or Xrossband dual-band mode. Its compact design and minimal weight make it ideal for long-range drones, FPV quads, and fixed-wing aircraft where signal integrity is critical. The integrated Wi-Fi module enables fast and easy firmware updates and configuration via WebUI, accessible from your mobile device or PC—no cables or drivers required. Whether flying in dense RF environments or pushing the limits of distance, the XR4 delivers the most robust, ultra-low-latency RF link available. Key Features:True Diversity & Dual-Band operation (2.4GHz + 900MHz Sub-G)ExpressLRS Gemini & Gemini Xrossband (Gem-X) protocol supportCompatible with ELRS 2.4GHz, Sub-G 900MHz, Gemini, and Gem-X modesHigh-performance ESP32D4 MCU for fast processingDual Semtech LR1121 RF transceivers for unmatched link stabilitySecondary UART port for telemetry or extended functionalityCastled pads for easier soldering and reliable connectionsBuilt-in Wi-Fi module for WebUI configuration and wireless firmware updates Specifications:Product: XR4 Gemini Xrossband Dual-Band ReceiverMCU: ESP32D4RF Chips: Dual Semtech LR1121RF Connectors: IPEX-1 × 2Antennas: Dual-Band T-type × 2 (included)Frequency Range: 2.4GHz / Sub-G 900MHzTelemetry Power: 100mWMax Refresh Rate: DK500Hz / K1000HzMin Refresh Rate: 50HzWorking Voltage: DC 4.5V – 8.4VWeight: 1.7g (without antennas)Dimensions: 22mm × 18mm × 4mmFirmware: ExpressLRS v3.5.1 (pre-installed)Firmware Target: RadioMaster XR4 2.4/900 Gemini RXBus Interfaces:– CRSF– UART Package Includes:1 × XR4 Gemini Xrossband Dual-Band ExpressLRS Receiver2 × Dual-Band T-Type Antennas1 × CRSF Connection Wire3 × Heat Shrink Tubes1 × Manual