HPXGRC 2.4GHz ExpressLRS ELRS Receiver Instruction Manual

1. Introduction

Thank you for choosing the HPXGRC 2.4GHz ExpressLRS (ELRS) Receiver. This ultra-lightweight and long-range receiver is designed for high-performance FPV freestyle drones and various DIY remote control projects. This manual provides essential information for the safe and effective setup, operation, and maintenance of your receiver. Please read it thoroughly before use.

2. Safety Information

• Always ensure correct polarity when connecting power to avoid damage to the receiver and other components.
• Operate RC equipment responsibly and within legal limits.
• Keep the receiver away from water, moisture, and extreme temperatures.
• Small components can be a choking hazard; keep out of reach of children.
• If soldering is required, ensure proper ventilation and use appropriate safety gear.

3. Package Contents

Verify that all items are present in your package:

• 1 x HPXGRC ELRS 2.4G Receiver
• 1 x Heat Shrink Tubing
• 4 x Connection Wires
• 1 x T-Antenna

4. Specifications

5. Setup Instructions

5.1. Wiring

Connect the receiver to your flight controller or other compatible device using the provided connection wires. Refer to the wiring diagram below for correct pin assignments:

• G: Ground
• V: Voltage (typically 5V, check your flight controller's specifications)
• R: RX (Receiver Data Input, connects to TX on flight controller)
• T: TX (Receiver Data Output, connects to RX on flight controller)

5.2. Antenna Installation

Connect the T-shaped dipole antenna to the IPEX1 connector on the receiver board. Ensure the connection is secure. Position the antenna away from carbon fiber frames and other electronic components for optimal signal reception.

5.3. Mounting

Mount the receiver securely on your drone or model. Due to its small size and light weight, it can be placed in various locations. Use the provided heat shrink tubing to protect the receiver from short circuits and environmental elements. Ensure it is not exposed to excessive vibration.

5.4. Binding Process (ExpressLRS)

The ELRS receiver requires binding with an ELRS transmitter module. Follow these general steps:

1. Flash Firmware (if necessary): Ensure both your ELRS transmitter module and receiver are running compatible ELRS firmware (version 3.3.1 or newer is recommended for this receiver). You may need to flash the receiver via passthrough or Wi-Fi if it's not already bound or running the correct version.
2. Power Cycle 3 Times: Power on your drone/receiver, then immediately power it off. Repeat this process three times. On the third power-up, the receiver's LED should flash rapidly, indicating it is in binding mode.
3. Activate Binding on Transmitter: On your ELRS transmitter module (e.g., via EdgeTX/OpenTX LUA script), select the 'Bind' option.
4. Confirmation: The receiver's LED should turn solid once successfully bound.

For detailed ELRS binding instructions and firmware updates, please refer to the official ExpressLRS documentation.

6. Operating Instructions

6.1. Power On

Once wired and bound, power on your drone/model. The receiver LED should illuminate solid, indicating a successful connection to your transmitter.

6.2. Signal and Telemetry

The ELRS system provides robust long-range control and telemetry feedback. Monitor your signal strength (RSSI/LQ) and other telemetry data (e.g., battery voltage if configured) via your transmitter's display. The 100mW telemetry output ensures reliable data transmission back to your radio.

7. Maintenance

• Keep Clean: Regularly inspect the receiver for dirt, dust, or debris. Use a soft, dry brush or compressed air to clean it.
• Check Connections: Periodically check all wiring connections for looseness or damage. Ensure the antenna is securely attached.
• Protect from Elements: While heat shrink tubing provides some protection, avoid prolonged exposure to moisture, direct sunlight, or extreme temperatures.
• Firmware Updates: Keep your ELRS firmware updated on both the receiver and transmitter for optimal performance and access to new features.

8. Troubleshooting

8.1. Receiver Not Binding

• Ensure both receiver and transmitter are running compatible ELRS firmware versions.
• Verify the 3-time power cycle sequence for binding mode is correctly performed.
• Check power and ground connections to the receiver.
• Try flashing the receiver firmware again, ensuring the correct target is selected.

8.2. No Signal / Intermittent Signal

• Inspect antenna connection for damage or looseness.
• Ensure the antenna is positioned optimally, away from obstructions like carbon fiber.
• Check for sources of interference near the receiver or antenna.
• Verify that the transmitter power output is set correctly.

8.3. No Telemetry Data

• Confirm that telemetry is enabled in your flight controller and transmitter settings.
• Check the RX/TX wiring between the receiver and flight controller.
• Ensure the flight controller UART is configured for CRSF protocol.

9. User Tips

• For optimal range and signal quality, ensure your antenna is mounted vertically and clear of any carbon fiber or metal parts of your drone.
• Consider using a small piece of double-sided foam tape to secure the receiver to prevent vibration-induced issues.
• Always perform a range check before flying, especially after making changes to your setup.

10. Warranty and Support

For warranty claims or technical support, please contact your retailer or the manufacturer directly. Keep your proof of purchase for any warranty-related inquiries. Detailed support resources and community forums for ExpressLRS can also be found online.