SPARKHOBBY ELRS 2.4G 5CH PWM ExpressLRS Receiver Instruction Manual

1. Introduction

This manual provides detailed instructions for the setup, operation, and maintenance of your SPARKHOBBY ELRS 2.4G 5CH PWM ExpressLRS Receiver. Please read this manual thoroughly before use to ensure proper functionality and safety. This receiver is designed for use with RC FPV fixed-wing drones, offering reliable 2.4GHz ExpressLRS communication.

2. Product Overview

The SPARKHOBBY ELRS 2.4G 5CH PWM Receiver (Model BK-2.4G-5CH) is a compact and efficient receiver for ExpressLRS systems. It features 5 PWM channels and supports both PWM and CRSF output protocols. The receiver includes a 2.0dBi 2.4G copper pipe antenna for optimal signal reception.

Figure 1: SPARKHOBBY ELRS 2.4G 5CH PWM Receiver with attached antenna.

Figure 2: Included 2.0dBi 2.4G copper pipe antenna.

3. Setup

3.1 Physical Connection

Connect the 2.0dBi 2.4G copper pipe antenna to the IPEX 1 connector on the receiver board. Ensure the connection is secure. Connect the receiver to your flight controller or power source using the appropriate wiring for PWM or CRSF protocol. The input voltage range is 4-10V.

Figure 3: Receiver pinout and dimensions (15.5mm x 25.5mm). Note the VBAT (34V Max) and GND connections, and the IPEX1 antenna connector.

3.2 Firmware Requirements

The receiver supports different firmware versions depending on its intended use:

• For 5-channel PWM receiver: Use DIY-2400-RX-PWMP firmware.
• For CRSF serial receiver: Use DIY-2400-RX-ESP8285-SX1280 firmware.

For voltage return functionality up to 34V, firmware version 3.0.0 or above is required.

Figure 4: Firmware description for different operating modes.

3.3 WIFI Configuration Interface

The ELRS PWM receiver allows configuration via a WIFI hotspot. This interface enables setting parameters such as PWM channel assignments, refresh frequency, and runaway protection.

1. Power on the receiver.
2. Wait for approximately 60 seconds. The receiver light will flash quickly, indicating it has entered WIFI hotspot mode.
3. On your computer or mobile device, connect to the WIFI hotspot named "ExpressLRS RX".
4. The password for the WIFI hotspot is "expresslrs".
5. Once connected, your device should automatically open the setting interface in a web browser. If not, open a web browser and navigate to http://10.0.0.1.
6. Configure the desired PWM channel settings, refresh frequency, and runaway protection parameters.

4. Operating

Once the receiver is properly set up, configured, and bound to your ExpressLRS transmitter, it will begin receiving control signals. Ensure your flight controller is correctly configured to interpret the PWM or CRSF signals from the receiver. Always perform a range check and verify all control surfaces respond correctly before flight.

5. Maintenance

To ensure the longevity and reliable performance of your receiver, follow these maintenance guidelines:

• Cleaning: Keep the receiver clean and free from dust, dirt, and moisture. Use a soft, dry cloth for cleaning. Avoid using solvents or harsh chemicals.
• Antenna Inspection: Regularly inspect the antenna and its IPEX 1 connector for any signs of damage, kinks, or loose connections. A damaged antenna can significantly reduce range and signal quality.
• Environmental Protection: Avoid exposing the receiver to extreme temperatures, direct sunlight for prolonged periods, or high humidity. Protect it from physical shock or vibrations.
• Firmware Updates: Periodically check the official ExpressLRS website for firmware updates. Updating firmware can provide new features, performance improvements, and bug fixes.

6. Troubleshooting

If you encounter issues with your ELRS receiver, refer to the following troubleshooting steps:

• No Signal / No Bind:
  • Ensure the receiver is powered correctly within the 4-10V range.
  • Verify that your ExpressLRS transmitter and receiver are running compatible firmware versions.
  • Re-initiate the binding process. For ExpressLRS, ensure both TX and RX have the same binding phrase or follow the specific binding procedure for your ExpressLRS module.
• Incorrect Channel Output / Unresponsive Controls:
  • Access the WIFI configuration interface (Section 3.3) to verify PWM channel assignments and refresh frequency settings.
  • Check your flight controller's configuration to ensure it is set to the correct receiver protocol (PWM or CRSF) and channel mapping.
• Intermittent Connection / Reduced Range:
  • Inspect the antenna for any damage or loose connections at the IPEX 1 port.
  • Ensure the antenna is positioned optimally and is not obstructed by carbon fiber frames, batteries, or other electronic components that can block RF signals.
  • Verify the telemetry power setting (12dbm) is appropriate for your setup and local regulations.
• Receiver Not Entering WIFI Mode:
  • Ensure the receiver is powered on for at least 60 seconds.
  • Check if the receiver light is flashing quickly. If not, there might be a power issue or a firmware problem.

7. Specifications

8. Warranty and Support

For warranty information, technical assistance, or any product-related inquiries, please contact your retailer or visit the official SPARKHOBBY website. Please retain your proof of purchase for any warranty claims. Unauthorized modification or disassembly of the product may void the warranty.