Introduction
The RadioMaster RP series of receivers are designed with size, ease of use, and range in mind. Utilizing ExpressLRS 2.4GHz Open-source firmware, the RP series of nano receivers deliver features and range that modern pilots expect.
Developed around the ESP8285 MCU and SX1280IMLTRT RF Chip, the RP series offers Lora and FLRC 2.4GHz RF links, providing incredible range and low latency. With built-in Wi-Fi, firmware updates can be performed on your craft without the need to remove the receiver. Binding can be achieved using a bind phrase, eliminating the need for bind plugs or complex button presses while connecting the battery.
Tiny in size yet big on features and range, the RP series of receivers are suitable for various applications, including whoops, drones, and fixed-wing aircraft. The RP2 features an improved PCB design for better heat dissipation, easier to solder pads, and an LED on the top side of the PCB.
Setup
1. Wiring Connection
The RP1 and RP2 receivers require a 5V power supply and connections for TX (Transmit) and RX (Receive) data lines to your flight controller. Ensure correct polarity and pin assignment to avoid damage.
- 5V: Connect to a stable 5V power source from your flight controller.
- TX: Connect to the RX pad of your flight controller's UART.
- RX: Connect to the TX pad of your flight controller's UART.
- GND: Connect to the ground pad of your flight controller.
2. Binding Procedure
The RP series receivers utilize a bind phrase for simplified binding. This eliminates the need for traditional bind plugs or complex button sequences.
- Ensure your transmitter is configured with the same ExpressLRS firmware version and bind phrase as your receiver.
- Power on your receiver.
- The receiver will automatically attempt to bind with the transmitter if the bind phrase matches.
- A solid LED on the receiver indicates a successful bind.
Note for RP2: The RP2 features an LED on the top side of the PCB for easier status indication.
3. Firmware Updates
The RP series receivers have built-in Wi-Fi for convenient firmware updates. This allows you to update the receiver's firmware without physically removing it from your craft.
- Power on the receiver.
- Connect to the receiver's Wi-Fi hotspot from your computer or mobile device.
- Access the receiver's web interface (usually via a specific IP address like 10.0.0.1 or similar, refer to ExpressLRS documentation for exact details).
- Upload the desired ExpressLRS firmware file through the web interface.
- After the update, the receiver will reboot.
Operating Instructions
Once the receiver is correctly wired and bound to your transmitter, it is ready for operation.
- Power on your RC model (which powers the receiver).
- Power on your RadioMaster transmitter.
- Ensure the receiver's LED indicates a solid connection (bound state).
- Verify control inputs on your flight controller's software (e.g., Betaflight, ArduPilot) to confirm proper communication between the receiver and flight controller.
- The ExpressLRS system provides low latency and high refresh rates for responsive control.
Maintenance
- Physical Inspection: Regularly check the receiver and antenna for any signs of damage, loose connections, or wear.
- Cleaning: Keep the receiver free from dust, dirt, and moisture. Use a soft, dry brush or compressed air for cleaning. Avoid using liquids.
- Antenna Placement: Ensure the antenna (especially the T-antenna on RP1) is positioned optimally for maximum signal reception and range. Avoid placing it near carbon fiber or large metal objects that can block the signal.
- Firmware: Periodically check for new ExpressLRS firmware releases. Updating to the latest stable version can provide performance improvements, bug fixes, and new features. Refer to the ExpressLRS project documentation for update procedures.
Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Receiver LED not solid (not bound) | Incorrect bind phrase, transmitter not powered, receiver not in bind mode. |
|
| No control input in flight controller software | Incorrect wiring, UART not configured, receiver not bound. |
|
| Poor range or signal loss | Antenna obstruction, damaged antenna, interference. |
|
Specifications
RadioMaster RP1 Nano Receiver
| Feature | Detail |
|---|---|
| Type | ISM |
| MCU | ESP8285 |
| RF Module | SX1280IMLTRT |
| Antenna | 65mm 2.4GHz T Antenna |
| Frequency Range | 2400 MHz to 2480 MHz |
| Max Receive Refresh Rate | 500Hz / F1000Hz |
| Min Receiver Refresh Rate | 25Hz |
| Working Voltage | 5V |
| Weight | 0.53g (without antenna) |
| Dimension | 13mm x 11mm x 3mm |
RadioMaster RP2 Nano Receiver
| Feature | Detail |
|---|---|
| Type | ISM |
| MCU | ESP8285 |
| RF Module | SX1280IMLTRT |
| Antenna | On Board SMT Antenna |
| Frequency Range | 2400 MHz to 2480 MHz |
| Max Receive Refresh Rate | 500Hz / F1000Hz |
| Min Receiver Refresh Rate | 25Hz |
| Working Voltage | 5V |
| Weight | 0.55g |
| Dimension | 13mm x 11mm x 7mm |
Warranty and Support
For warranty claims, technical support, or further assistance, please contact the seller or the official RadioMaster support channels. Keep your purchase records for any warranty-related inquiries.
For detailed information regarding the open-source ExpressLRS firmware, please refer to the official ExpressLRS project documentation and community forums.
User Tips
- Antenna Orientation: For optimal signal strength and range, ensure the T-antenna on the RP1 is oriented perpendicular to the main body of your aircraft, and away from conductive materials.
- Heat Management (RP2): While the RP2 has improved heat dissipation, ensure it is installed in a location with adequate airflow, especially in enclosed spaces, to prevent overheating.
- Firmware Consistency: Always ensure your receiver and transmitter are running compatible versions of ExpressLRS firmware for reliable operation.
- Bind Phrase Security: Use a unique and strong bind phrase to prevent unauthorized connections to your receiver.
