1. Isingeniso
The Radiomaster ER4 2.4GHz 4CH ExpressLRS (ELRS) PWM Receiver is engineered for high performance, reliability, and flexible configuration in various remote-controlled applications. Based on the revolutionary ExpressLRS system, it offers fast response speeds and ultra-long range capabilities. This receiver is designed to provide precise control and essential telemetry data for fixed-wing aircraft, RC cars, boats, and tanks.
Key features include built-in receiver voltage telemetry, flight battery telemetry with automatic voltage detection, and support for Wi-Fi updates and WEBUI configuration. Its robust design ensures durability and ease of use for enthusiasts and hobbyists.

Figure 1: Radiomaster ER4 PWM Receiver highlighting its compact design. This receiver is lightweight and small, making it suitable for various small aircraft, boats, and cars.
2. Okuqukethwe Kwephakheji
- 1x Radiomaster ER4 2.4GHz 4CH ExpressLRS ELRS PWM Receiver
- 1x ivolumutage Telemetry Wire
- 1x Intambo ye-CRSF
- 1x ELRS-RX-SBUS Wire
- 1x User Card

Figure 2: The Radiomaster ER4 receiver shown in its retail packaging with included wires and user card.
3. Imininingwane
- Imodeli: ER4
- Imvamisa: 2.4GHz
- Iziteshi: 4 PWM Channels
- Okokufaka Voltage: 4.5V - 8.4V DC
- Ubukhulu: 1.85 x 1.3 x 0.58 inches (approx. 30mm x 15mm x 5mm)
- Isisindo: Cishe amagremu angu-2.69
- I-Antenna: High sensitivity 20 cm dual antenna with UFL connector
- I-Telemetry: Built-in receiver voltage telemetry, flight battery telemetry (with external input)
- Ukucushwa: Wi-Fi updates and WEBUkucushwa kwe-UI
- Isixhumi esibonakalayo: 4-wire CRSF interface for optional telemetry sensors

Figure 3: Detailed dimensions of the Radiomaster ER4 receiver, showing its compact size for easy integration.

Figure 4: The Radiomaster ER4 receiver displayed on a digital scale, indicating its lightweight design at approximately 2.69 grams.
4. Setha
4.1 Ukuxhuma Isamukeli
The ER4 receiver features standard PWM pin headers for connecting servos and power. Ensure correct polarity when connecting power (4.5V - 8.4V DC) to the designated BAT pins.

Umfanekiso 5: Ngaphambili view of the Radiomaster ER4 receiver, showing the PWM output pins (CH1-CH4) and battery input (BAT).
4.2 Ukufakwa kwe-Antenna
The ER4 receiver comes with a high sensitivity 20 cm dual antenna. It connects via a UFL connector. Ensure the antenna is securely attached and positioned for optimal signal reception.

Umfanekiso 6: Vala-up view of the UFL antenna connector on the Radiomaster ER4 receiver, next to the BOOT button.
4.3 Binding Procedure (Traditional Binding)
Ngokubophezela okuvamile, umushwana obophayo kufanele ubekwe kuphawulwe kokuthi user_defines ku-RX.
- Cima isidlulisi sakho.
- Xhuma futhi ukhiphe isamukeli sakho izikhathi ezintathu.
- Qiniseka ukuthi i-LED yenza ukucwayiza okuphindwe kabili okusheshayo, okubonisa ukuthi umamukeli ukumodi yokubopha.
- Use the [BIND] button on the ExpressLRS Lua script, which sends out a binding pulse.
- If the receiver has a solid light, it's bound!
Video 1: This video demonstrates the binding process for Radiomaster ER series receivers, including the ER4. It shows the power cycling method and interaction with the transmitter's LUA script for successful binding.
5. Izindlela Zokusebenza Nezici
5.1 Izincazelo zesikhombi se-LED
| Ukukhanya Kwesimo | Incazelo |
|---|---|
| Ukukhanya okunensayo (500ms) | Ilinde isidlulisi |
| Ukukhanya okusheshayo (25ms) | I-Wi-Fi ivuliwe |
| I-flash kabili | Isamukeli sikwimodi yokubopha |
| I-flash kathathu | Ukusebenza komamukeli, iphutha lokukhetha imodi |
| Ukukhanya okuqinile | Receiver functional (Connected) |
5.2 Umqtage Telemetry
The ER4 receiver supports built-in receiver voltage telemetry and can also provide flight battery telemetry with automatic detection of voltage input when an external battery is connected to the EXT-V port.
5.3 Wi-Fi Update and Configuration
The receiver supports Wi-Fi updates and WEBUI configuration, ensuring your receiver is always up-to-date and easily configurable. This allows for convenient firmware upgrades and parameter adjustments.
6. Isondlo
- Keep the receiver clean and free from dust or debris.
- Regularly check all wire connections for secure fit and signs of wear.
- Ensure the antenna is not damaged and is positioned optimally for signal reception.
- Perform firmware updates via Wi-Fi as recommended by Radiomaster for optimal performance and new features.
7. Ukuxazulula izinkinga
- Ukwehluleka Kokubopha: Ensure your transmitter's ExpressLRS LUA script is updated and the binding phrase is correctly set or commented out on the receiver. Follow the binding procedure carefully.
- Ayikho Idatha ye-Telemetry: Verify all telemetry wires are correctly connected. For external battery telemetry, ensure the battery is properly connected to the EXT-V port.
- Isignali Yesikhashana: Check antenna placement and ensure it is not obstructed by carbon fiber or other conductive materials. Ensure the antenna is securely connected to the UFL port.
- Receiver Not Powering On: Hlola ukuxhumeka kwamandla bese uqinisekisa ukuthi ivolumu yokufaka iyasebenzatage is within the specified 4.5V - 8.4V range.
8. Iwaranti kanye Nokusekela
For warranty claims, technical support, or further assistance, please refer to the contact information provided on the user card included in your package or visit the official Radiomaster webindawo.





