Receiver Radiomaster DBR4 Dual Band Xross Gemini ExpressLRS

The DBR4 GemX Receiver is the cornerstone of dependable FPV control systems. Its Gemini Xrossband technology enables simultaneous reception on both 2.4 GHz and 900 MHz, dramatically boosting signal resilience in high-interference environments.

Equipped with dual Semtech LR1121 RF chips and the powerful ESP32 MCU, this receiver achieves blazing refresh rates of 500 Hz, with firmware v3.4 on the horizon offering an optimal 1000 Hz for ultra-responsive control.

Despite packing cutting-edge hardware, the DBR4 maintains a minimal footprint—just 2.7 g w/o antennas, with versatile 20×20 mm mounting and wide 4.5–8.4 V input range. Its four discrete antennas ensure unmatched reception and flexible placement options.

When reliability is non-negotiable—long-range flights, complex urban environments, or first-person view racing—the DBR4 brings unbeatable performance, packet integrity, and signal consistency.

Key Specifications:

• Receiver: DBR4 Gemini Xrossband ExpressLRS Receiver

• Radio Frequency Bands: 2.4 GHz (2.404–2.479 GHz) / 900 MHz (903.5–926.9 MHz)

• RF Chips: Semtech LR1121 ×2

• MCU: ESP32

• Telemetry RF Power: Max 100 mW per band

• Refresh Rates: Up to 500 Hz (1000 Hz in ELRS v3.4) — min 50 Hz

• Working Voltage: 4.5–8.4 V DC

• Bus Interface: CRSF (Crossfire)

• Frame Size: 27.2 × 27.2 mm (20×20 mm mounting)

• Weight: 2.70 g (no antennas), 5.30 g (with antennas)

• Firmware: ExpressLRS v3.3.2 pre-installed

• Antennas Included: 2× 2.4 GHz wires, 2× 900 MHz wires (LHCP)

• Features: Dual-band Gemini Xrossband, Speed Boost, upcoming K Modes, Canvas OSD supported