RadioMaster XR3 Nano Dual-Band ExpressLRS Receiver

Compact Dual-Band ExpressLRS Receiver with Antenna Diversity

The RadioMaster XR3 is a powerful and ultra-compact Dual-Band ExpressLRS receiver designed for FPV drones, fixed-wing and VTOL systems, as well as a wide range of other RC applications. With dimensions of only 22 × 15 × 4 mm and a weight of just 1.3 g without antennas, the receiver can be easily integrated into compact platforms.

At the heart of the RadioMaster XR3 is the modern Semtech LR1121 transceiver combined with a powerful ESP32C3 microcontroller. The receiver supports both the 2.4 GHz and Sub-G 900 MHz frequency bands and is supplied in this version with two dual-band T-antennas.

Combined with ExpressLRS, the RadioMaster XR3 provides a powerful and flexible radio platform for applications requiring a compact form factor, high reception quality, and support for multiple frequency bands.

Dual-Band 2.4 GHz & Sub-G 900 MHz

The dual-band version of the RadioMaster XR3 supports both 2.4 GHz and the Sub-G 900 MHz frequency range. This allows the receiver to be used flexibly within compatible ExpressLRS systems.

The two included dual-band T-antennas are designed for operation across both supported frequency ranges, providing flexible installation options for different FPV and RC platforms.

• Dual-Band ExpressLRS receiver
• 2.4 GHz support
• Sub-G 900 MHz support
• 2 × dual-band T-antennas
• 2 × IPEX-1 RF connectors

Antenna Diversity

The RadioMaster XR3 features two antenna connectors and supports Antenna Diversity. By using two antennas positioned separately on the aircraft or vehicle, reception can be improved as the orientation and attitude of the platform change during operation.

This diversity configuration is particularly beneficial for FPV, Long Range, fixed-wing, and VTOL applications, where the orientation of the platform and therefore the antennas can continuously change during flight.

Semtech LR1121 Transceiver

The RadioMaster XR3 is based on the Semtech LR1121 third-generation RF transceiver. The LR1121 provides the foundation for the receiver's multi-frequency capability and enables ExpressLRS operation across the supported frequency bands.

The receiver supports a maximum receive refresh rate of up to DK500Hz / K1000Hz and a minimum receiver refresh rate of 25 Hz.

ESP32C3 Microcontroller

A powerful ESP32C3 microcontroller handles the ExpressLRS functions of the RadioMaster XR3 while also enabling additional features such as integrated Wi-Fi connectivity.

Integrated Wi-Fi & WebUI

The RadioMaster XR3 features integrated Wi-Fi, allowing convenient configuration and firmware updates without requiring additional programming hardware.

Compatible settings can be managed through the ExpressLRS WebUI directly from a web browser on a computer, smartphone, or tablet.

CRSF & Additional UART

In addition to the primary CRSF interface, the RadioMaster XR3 features an additional UART port. This provides further connectivity options for compatible hardware and advanced applications.

• Bus Interface 1: CRSF
• Bus Interface 2: UART
• Additional UART port
• Secondary connection for extended functionality

Compact Integration

With its compact dimensions and low weight, the RadioMaster XR3 is suitable for a wide range of RC platforms. Castled pads simplify soldering and enable clean integration of the receiver into the respective platform.

The input voltage range of 4.5 to 8.4 V DC provides flexible power supply options within compatible RC systems.

ExpressLRS

ExpressLRS is a powerful open-source radio control system for RC applications designed for low latency, high update rates, and reliable radio links.

The RadioMaster XR3 is supplied with pre-installed ExpressLRS v3.5.1 firmware. The corresponding firmware target is RadioMaster XR3 2.4/900 Diversity RX.

Features

• Dual-Band ExpressLRS receiver
• 2.4 GHz and Sub-G 900 MHz
• Antenna Diversity
• 2 × dual-band T-antennas
• 2 × IPEX-1 RF connectors
• Semtech LR1121 transceiver
• ESP32C3 high-performance MCU
• Integrated Wi-Fi
• Configuration via ExpressLRS WebUI
• Firmware updates via Wi-Fi
• Additional UART port
• Secondary port for extended functionality
• CRSF interface
• Castled pads for easy soldering
• Compact and lightweight design

Technical Specifications

• Product: RadioMaster XR3 Nano Multi-Frequency Antenna Diversity ExpressLRS Receiver
• Version: Dual-Band
• MCU: ESP32C3
• RF Chip: Semtech LR1121
• RF Connectors: 2 × IPEX-1
• Antennas: 2 × dual-band T-antennas
• Frequency Range: 2.4 GHz / Sub-G 900 MHz
• Telemetry Transmit Power: 100 mW
• Maximum Receive Refresh Rate: DK500Hz / K1000Hz
• Minimum Receiver Refresh Rate: 25 Hz
• Operating Voltage: DC 4.5–8.4 V
• Weight: 1.3 g without antennas
• Dimensions: 22 × 15 × 4 mm
• Firmware: ExpressLRS v3.5.1 pre-installed
• Firmware Target: RadioMaster XR3 2.4/900 Diversity RX
• Bus Interface 1: CRSF
• Bus Interface 2: UART

Ideal for FPV, Long Range & Fixed Wing

The combination of dual-band support, Antenna Diversity, compact dimensions, and ExpressLRS makes the RadioMaster XR3 a versatile receiver for a wide range of RC platforms.

• FPV drones
• Freestyle FPV
• Cinematic FPV
• Long Range FPV
• Fixed-wing systems
• VTOL platforms
• Other RC applications

Package Contents

• 1 × RadioMaster XR3 Nano Multi-Frequency Antenna Diversity ExpressLRS Receiver
• 2 × dual-band T-antennas for 2.4 GHz / Sub-G 900 MHz
• 1 × CRSF cable
• 3 × heat-shrink tubes
• 1 × manual card