RadioMaster XR3 Nano 2.4GHz ExpressLRS Receiver

Compact 2.4 GHz ExpressLRS Receiver with Antenna Diversity

The RadioMaster XR3 is a powerful and ultra-compact 2.4 GHz ExpressLRS receiver for FPV drones, fixed-wing and VTOL systems, as well as 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 even into compact platforms.

At the heart of the RadioMaster XR3 is the modern Semtech LR1121 transceiver combined with a powerful ESP32C3 microcontroller. In this version, the receiver is designed for operation in the 2.4 GHz frequency band and is supplied with two matching 2.4 GHz T-antennas.

Combined with ExpressLRS, the RadioMaster XR3 provides a powerful radio platform for applications requiring a compact form factor, high update rates, and a reliable control and telemetry link.

ExpressLRS 2.4 GHz

The 2.4 GHz version of the RadioMaster XR3 combines the advantages of ExpressLRS with a compact diversity receiver. The system is suitable for a wide range of FPV and RC platforms and provides a powerful solution for modern control and telemetry applications.

• ExpressLRS 2.4 GHz
• 2 × 2.4 GHz T-antennas
• 2 × IPEX-1 RF connectors
• Antenna Diversity
• 100 mW telemetry transmit power

Antenna Diversity

The RadioMaster XR3 features two separate antenna connectors and supports Antenna Diversity. By using two antennas positioned in different locations on the platform, reception can be improved, particularly as the orientation and attitude of the model change during operation.

This is especially beneficial for FPV drones, fixed-wing aircraft, and VTOL systems, where the position and orientation of the platform can change continuously during flight.

Semtech LR1121 Transceiver

The RadioMaster XR3 is based on the Semtech LR1121 third-generation RF transceiver. Combined with ExpressLRS, the platform provides a high-performance radio link with high update rates and extensive configuration options.

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 and also enables additional features such as integrated Wi-Fi connectivity.

Integrated Wi-Fi & WebUI

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

Compatible settings can be managed directly through the ExpressLRS WebUI using 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 connection and integration 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 dimensions of only 22 × 15 × 4 mm and a weight of 1.3 g without antennas, the RadioMaster XR3 is also suitable for compact and weight-sensitive platforms.

Castled pads simplify soldering and enable clean integration into the respective platform. The input voltage range of 4.5 to 8.4 V DC also provides flexible power supply options.

ExpressLRS Firmware

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

• ExpressLRS 2.4 GHz receiver
• Antenna Diversity
• 2 × 2.4 GHz T-antennas
• 2 × IPEX-1 RF connectors
• Semtech LR1121 transceiver
• ESP32C3 high-performance MCU
• 100 mW telemetry transmit power
• 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: 2.4 GHz
• Type: ISM2.4
• MCU: ESP32C3
• RF Chip: Semtech LR1121
• RF Connectors: 2 × IPEX-1
• Antennas: 2 × 2.4 GHz T-antennas
• Frequency Range: 2.4 GHz
• 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, Fixed Wing & VTOL

The combination of ExpressLRS 2.4 GHz, Antenna Diversity, compact dimensions, and an additional UART interface makes the RadioMaster XR3 a versatile solution 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 × 2.4 GHz T-antennas
• 1 × CRSF cable
• 3 × heat-shrink tubes
• 1 × manual card