Description
Radiomaster DBR4 Dual Band 2.4G&900MHZ Xross Gemini ExpressLRS Receiver 20x20mm Perfec — BOLTON SKU 63644.
About the Radiomaster DBR4 Dual-Band ExpressLRS Receiver
RadioMaster builds the DBR4 as a dual-band Gemini receiver. It runs an ESP32 microcontroller with two Semtech LR1121 radio chips, allowing it to receive on 2.4 GHz and 900 MHz at the same time rather than switching between bands. Frequency coverage is 2.404 to 2.479 GHz and 903.5 to 926.9 MHz. Packet rates run from 50 Hz up to 500 Hz, and telemetry transmits at up to 100 mW. Operating voltage is 4.5 to 8.4 V DC, so the receiver can be fed from a 2S supply or a regulated BEC. Control data leaves the receiver over a CRSF bus. The board measures 27.20 by 27.20 mm with a 20 by 20 mm mounting pattern and weighs 2.70 g bare, or 5.30 g with its four wire antennas fitted.
Key specifications
| Microcontroller | ESP32 |
|---|---|
| RF chipset | Semtech LR1121 × 2 |
| Frequency ranges | 2.404–2.479 GHz / 903.5–926.9 MHz |
| Packet rate | 50 Hz to 500 Hz |
| Telemetry RF power | Max 100 mW |
| Operating voltage | 4.5 to 8.4 V DC |
| Bus interface | CRSF |
| Dimensions | 27.20 × 27.20 mm; 20 × 20 mm mounting |
| Weight | 2.70 g without antennas; 5.30 g with |
| Antennas | 2 × 2.4 GHz and 2 × 900 MHz wire |
Typical applications
A dual-band Gemini receiver is fitted to UAV and RC airframes where link robustness in congested radio environments is the driver, since the same control data arrives on two bands at once. The 20 by 20 mm hole pattern matches common flight-controller stacks. CRSF output connects directly to flight controllers running ExpressLRS-compatible firmware.
Supplied by BOLTON Technical Equipment Supplies against request for quotation. Add this item to your RFQ basket to request pricing, lead time and documentation requirements (e.g. CoC, datasheets or test reports where applicable).
Reviews
There are no reviews yet.