1. Introduction
The FrSky R-XSR is an ultra-miniature redundancy receiver, representing an evolution of the full-range XSR receiver. It integrates all the functionalities of the XSR receiver while being significantly smaller and lighter. This receiver incorporates a redundancy function for enhanced security and features IPEX connectors for convenient antenna replacement. It is designed for use in FPV racing drones and other remote-controlled aircraft requiring compact and reliable receiving solutions.
2. Product Overview
Image 1: The FrSky R-XSR Mini Redundancy Receiver, showcasing its compact size and dual antennas.
Key Features:
- Ultra-miniature size and lightweight design.
- Supports redundancy function for enhanced signal reliability.
- Integrated telemetry and Smart Port enabled.
- Features IPEX connectors for easily replaceable antennas.
- Switchable SBUS/CPPM signal output.
- Firmware upgradable for future compatibility and improvements.
- Compatible with FrSky X Series modules and radios in D16 mode.
Specifications:
| Parameter | Value |
|---|---|
| Dimensions | 16mm x 11mm x 5.4mm (L*W*H) |
| Weight | 1.5g |
| Number of Channels | 16CH (1-16CH from SBUS, 1-8CH from CPPM) |
| Operating Voltage Range | 4V - 10V |
| Firmware | Upgradable |
| Compatibility | FrSky X Series modules and radios (D16 mode) |
| Connectivity Technology | RF |
| Control Type | Remote Control |
3. Setup and Installation
3.1 Physical Installation
Due to its compact size, the R-XSR receiver can be installed in various locations within your FPV drone frame. Ensure it is mounted securely to minimize vibration and protect it from physical damage. Avoid placing it directly next to high-current components or video transmitters to prevent signal interference.
Image 2: Top view of the R-XSR receiver board, showing the main chip and connector pins.
3.2 Wiring
Connect the R-XSR receiver to your flight controller using the provided wiring harness. The standard connections are:
- VCC: Connect to a 4-10V power source from your flight controller.
- GND: Connect to the ground of your flight controller.
- SBUS/CPPM: Connect to the appropriate serial receiver input on your flight controller. The output mode is switchable (see Section 4.1).
- Smart Port (S.Port): Connect to a free UART TX pad on your flight controller for telemetry data.
Image 3: Bottom view of the R-XSR receiver board, showing solder pads and component layout.
3.3 Antenna Placement
The R-XSR uses IPEX connectors for its antennas, allowing for easy replacement. For optimal signal reception, ensure the antennas are:
- Mounted at a 90-degree angle to each other.
- Clear of carbon fiber, metal, and other conductive materials.
- Positioned away from motors, ESCs, and video transmitters.
Image 4: Close-up view of the IPEX connectors on the R-XSR receiver, where antennas are attached.
4. Binding Procedure
To establish communication between your FrSky transmitter and the R-XSR receiver, a binding process is required. Ensure your transmitter's internal RF module firmware is compatible with the receiver's firmware (e.g., ACCST D16 V2 or ACCESS).
- Turn on your FrSky transmitter and navigate to the Model Setup menu.
- Select the appropriate RF mode (e.g., D16) and channel range.
- Select the 'Bind' option on your transmitter. The transmitter's RF module will enter binding mode.
- While holding down the F/S (Fail-Safe) button on the R-XSR receiver, power on the receiver. The red and green LEDs on the receiver will illuminate, indicating it is in binding mode.
- Once the binding is successful, the red LED on the receiver will turn off, and the green LED will flash slowly.
- Exit binding mode on your transmitter.
- Power cycle both the transmitter and receiver. The green LED on the receiver should now be solid, indicating a successful connection.
Note: If you encounter issues, ensure your transmitter's internal RF module firmware is updated to a compatible version (e.g., V2 for ACCST D16) before attempting to bind.
5. Operating Modes
5.1 SBUS/CPPM Output
The R-XSR receiver supports both SBUS and CPPM signal outputs, which can be switched as needed. By default, the receiver outputs SBUS. To switch between modes:
- SBUS Mode: Short press the F/S button for 4 seconds. The blue LED will flash three times, indicating the switch to SBUS mode.
- CPPM Mode: Short press the F/S button for 4 seconds. The blue LED will flash once, indicating the switch to CPPM mode.
After switching, power cycle the receiver for the change to take effect.
5.2 Telemetry and Smart Port
The R-XSR provides full telemetry capabilities via its Smart Port (S.Port). This allows for real-time monitoring of flight controller data such as battery voltage, RSSI (Received Signal Strength Indicator), and other sensor information directly on your FrSky transmitter. Ensure the S.Port wire is connected to a telemetry-enabled UART on your flight controller and configured correctly in your flight controller software (e.g., Betaflight, iNav).
6. Firmware Update
FrSky periodically releases firmware updates for its receivers to improve performance, add features, or ensure compatibility with new transmitters. To update the R-XSR firmware:
- Download the latest firmware file for the R-XSR from the official FrSky website.
- Connect the R-XSR receiver to your FrSky transmitter's Smart Port (S.Port) using a suitable cable (often a specific adapter cable is required, not always included).
- Power on your transmitter and navigate to the SD card menu to locate the firmware file.
- Select the firmware file and initiate the update process. Follow the on-screen prompts on your transmitter.
- Once the update is complete, power cycle the receiver and transmitter.
Caution: Always use the correct firmware version for your region (e.g., EU LBT or FCC) and ensure compatibility with your transmitter's firmware to avoid operational issues.
7. Maintenance
Proper maintenance ensures the longevity and reliable operation of your R-XSR receiver:
- Physical Inspection: Regularly check the receiver and antennas for any signs of damage, such as bent pins, frayed wires, or cracked casing.
- Antenna Care: Ensure antennas are not kinked or cut. Replace damaged antennas promptly using the IPEX connectors.
- Environmental Protection: Protect the receiver from moisture, dust, and extreme temperatures. Consider conformal coating for enhanced water resistance in FPV applications.
- Secure Mounting: Verify that the receiver remains securely mounted to prevent disconnections or damage during flight.
8. Troubleshooting
This section addresses common issues you might encounter with the R-XSR receiver.
| Problem | Possible Cause | Solution |
|---|---|---|
| Receiver not binding | Incompatible firmware (transmitter/receiver); incorrect binding procedure. | Update transmitter's internal RF module to V2 (for D16) or compatible ACCESS firmware. Ensure correct binding steps are followed. |
| No signal/Failsafe | Antenna damage/poor placement; range issues; power supply problem. | Check antenna connections and placement. Replace damaged antennas. Verify power supply to the receiver. Perform a range test. |
| Telemetry not working | Incorrect S.Port wiring; flight controller UART not configured for telemetry. | Verify S.Port connection to a TX pad. Configure the corresponding UART for Smart Port telemetry in flight controller software. |
| Receiver gets hot/burns out | Over-voltage; short circuit; faulty unit. | Ensure operating voltage is within 4-10V. Check wiring for shorts. If issue persists, the unit may be faulty and require replacement. |
9. Specifications
Detailed technical specifications for the FrSky R-XSR Mini Redundancy Receiver.
| Parameter | Value |
|---|---|
| Brand | FrSky |
| Model Name | R-XSR |
| Dimensions | 16mm x 11mm x 5.4mm (0.63"L x 0.43"W x 0.21"H) |
| Weight | 1.5g (0.05 oz) |
| Number of Channels | 16CH (1-16CH from SBUS, 1-8CH from CPPM) |
| Operating Voltage Range | 4V - 10V |
| Firmware | Upgradable |
| Compatibility | FrSky X Series modules and radios (D16 mode) |
| Connectivity Technology | RF |
| Control Type | Remote Control |
| Operating Temperature | Up to 50 Degrees Celsius |
| UPC | 092685800716 |
| Manufacturer Part Number | 03022441 |
10. Warranty and Support
For warranty information, technical support, and further assistance, please refer to the official FrSky website or contact your authorized FrSky dealer. Keep your proof of purchase for any warranty claims.
FrSky provides customer service and technical support to assist with product inquiries, setup guidance, and troubleshooting. Refer to the official FrSky channels for the most current support contact information.
