The ER3 PRO is a compact receiver designed for installations where space is limited but link reliability and system access remain important. Despite its small footprint, it retains a full-featured RF and telemetry interface, making it well suited for clean, space-constrained builds.

Note on FCC Certification:
Due to current FCC regulations classifying this product as a foreign-produced UAS component, we are currently unable to obtain FCC certification. This item cannot be shipped to or sold in the United States at this time. 

Please note this is the pre-order; Orders start shipping at the end of September.

Features

• ExpressLRS Performance: Low latency, high reliability, and excellent link quality with flexible configuration options.
• Dual-Band Gemini X (2.4GHz + Sub-G 900MHz): Utilizes both frequency bands to provide enhanced link reliability across a wide range of operating environments.
• Up to 100mW Telemetry Output: Increased telemetry output power for improved data reliability and range.
• 3 PWM Outputs + Serial Support: Compact PWM output with CRSF and SBUS options.
• External UART Port (Locking Connector): Dedicated interface for telemetry, external devices, and system expansion.
• Independent Multi-Source Voltage Telemetry: Monitor up to two power sources simultaneously using dedicated ADC channels: EXT-V (up to 70V), receiver supply voltage (V-PWM) (up to 12V).
• MMCX Antenna Connectors: Durable, replaceable antennas with a secure connection.
• Wi-Fi Updates & WebUI: Configure and update directly without disassembly.
• Durable Injection-Molded Housing: Compact, protective enclosure for long-term reliability.
• Application: A compact, full-featured receiver for models that require advanced RF performance, telemetry, and connectivity in a space-efficient package.
• Compatibility: Compatible with all ExpressLRS transmitters and modules, including radios with built-in ELRS. 

At its core is the ExpressLRS system, built around dual Semtech LR1121 transceivers and a dual-band Gemini X RF architecture operating on both 2.4 GHz and Sub-G 900 MHz. Combined with up to 100mW telemetry output power, it provides a stable control link and enhanced telemetry performance for applications where reliable telemetry data is important.

With 3 PWM outputs, serial protocol support, and dual independent voltage telemetry channels, the ER3 PRO integrates easily into a wide range of aircraft and vehicle platforms. Dedicated ADC channels independently monitor receiver supply voltage (V-PWM) (up to 12V) and EXT-V (up to 70V), providing accurate telemetry for each voltage source. Locking connectors on the UART and EXT-V telemetry ports help ensure secure, reliable connections in demanding operating environments.

Serviceability is built in. Robust MMCX antenna connectors provide secure attachment and easy replacement, while the durable injection-molded housing delivers long-term protection in a compact form factor.

⚠️ Power Input & Voltage Notice

EXT-V Telemetry Input:

The maximum input voltage for the EXT-V external voltage telemetry reading is 70V. Do not exceed 70V, as this may damage the receiver.
The EXT-V input is accessed through the 2-pin JST-GH connector. Connect the red wire to the positive (+) terminal of the battery or ESC. The ER3 PRO provides independent ADC channels for EXT-V and receiver supply voltage (V-PWM).

Servo Power:

Ensure the ESC’s BEC can provide sufficient current for the servos being used. For high-voltage, high-torque servos, a 2S 7.4V battery or a suitable high-current UBEC is recommended.

Specification