RadioMaster RP3-H ExpressLRS 2.4GHz Nano Receiver

Product Overview

The RP3-H ExpressLRS receiver is designed for use with Nexus Helicopter Flybarless control units and is compatible with all CRSF/S.BUS enabled flight controllers. It features a built-in TCXO and an integrated housing for enhanced durability and ease of mounting on modern helicopter frames. The RP3-H provides reliable, stable, and accurate signal reception, improving flight experience and performance, especially in demanding environments. It also includes an Ext-V telemetry input for compatibility with older ESCs that do not provide battery voltage telemetry via the control unit.

The receiver utilizes the Skyworks SKY66112 power amplifier, delivering up to 100mW of telemetry power and antenna switching for diversity. It is built around the ESP8285 MCU and SX1281IMLTRT RF Chip, supporting Lora and FLRC 2.4GHz RF links for incredible range and low latency. Integrated Wi-Fi allows for firmware updates directly on the craft without removing the receiver.

TCXO (Temperature Compensated Crystal Oscillator)

The TCXO ensures high stability and accuracy in frequency control by compensating for temperature variations. This results in consistent and reliable signal reception, even under extreme temperature conditions. It also minimizes frequency drift over time, providing long-term frequency stability and preventing signal degradation. Learn more about the TCXO at: https://www.expresslrs.org/hardware/crystal-frequency-error.

RP3-H Specifications

Pinout Diagram Description

The receiver features a pinout with the following connections:

• TX (Green wire)
• RX (Blue wire)
• VCC (Red wire)
• GND (Black wire)

There are also BOOT and EXT-V (External Voltage) ports labeled on the device.

Binding Procedures

Chinese Binding Method (对频方法)

1. Turn off the transmitter.
2. Power cycle the receiver three times. The receiver's LED will flash twice, indicating it is in bind mode.
3. Turn on the transmitter and navigate to the ExpressLRS Lua script interface. Select [BIND] and confirm.
4. A solid LED on the receiver indicates successful binding.

Traditional Binding

For traditional binding, the binding phrase must be commented out in user_defines on the RX.

1. Power off your transmitter.
2. Plug in and unplug your receiver three times.
3. Ensure the LED is performing a quick double blink, signifying the receiver is in bind mode.
4. Use the [BIND] button on the ExpressLRS Lua script to send a binding pulse.
5. If the receiver shows a solid light, it is bound.

LED Status Indicators