1. Inngangur
The RADIOMASTER XR4 Gemini Xrossband Dual-Band Receiver is designed for remote control applications, offering reliable signal reception through its dual-band capabilities. It supports ExpressLRS Gemini Xrossband (Gem-X) protocol, operating on both 2.4GHz and Sub-G 900MHz frequencies. This manual provides essential information for the proper setup, operation, and maintenance of your XR4 receiver.
2. Innihald pakka
Gakktu úr skugga um að allir hlutir sem taldir eru upp hér að neðan séu innifaldir í pakkanum þínum:
- 1 x XR4 Gemini Xrossband Dual-Band Receiver
- 2 x Dual-Band T-Antenna
- 1 x CRSF Wire
- 3 x hitakrimpandi rör
This image displays the Radiomaster XR4 receiver board with its two dual-band T-antennas attached, illustrating the complete receiver assembly.
3. Eiginleikar
- True Diversity & Dual-Band: Utilizes dual LR1121 RF transceivers for enhanced reliability.
- ExpressLRS Gemini Xrossband (Gem-X) Compatible: Supports 2.4GHz and Sub-G 900MHz bands.
- Háafkastamikill örgjörvi: Equipped with ESP32D4.
- Dual Semtech LR1121 Transceivers: Provides robust signal processing.
- Secondary UART Port: For advanced functionality and future expansion.
- Castled Pads: Facilitates easy soldering.
- Integrated Wi-Fi Module: Simplifies firmware updates and configuration via WebHÍ.
- Ultra-Low Latency & High Refresh Rate: Ensures stable RF link.
This image highlights the two Semtech LR1121 transceivers, which are central to the receiver's dual-band and true diversity capabilities.
Þessi mynd sýnir ítarlega view of the XR4 receiver board, specifically pointing out the additional UART port available for future expansion and advanced functionality.
4. Tæknilýsing
| Parameter | Gildi |
|---|---|
| MCU | ESP32D4 |
| RF flís | LR1121 x 2 |
| RF tengi | IPEX-1 x 2 |
| Loftnet | Dual-Band T Antenna x 2 (Included) |
| Tíðnisvið | 2.4GHz / Sub-G 900MHz |
| Telemetry Power | 100mW |
| Maximum Receive Refresh Rate | DK500Hz / K1000Hz |
| Minimum Receiver Refresh Rate | 50Hz |
| Vinnandi binditage | DC 4.5-8.4V |
| Þyngd (án loftnets) | 1.7g |
| Mál | 22mm x 18mm x 4mm |
| Firmware Version (pre-installed) | ExpressLRS v3.5.1 |
| FW markmið | RadioMaster XR4 2.4/900 Gemini RX |
| Strætóviðmót 1 | CRSF |
| Strætóviðmót 2 | UART |
Þessi mynd sýnir skýra mynd ofan frá view of the XR4 receiver's circuit board, showing component layout and connection points.
Þessi mynd sýnir hliðarpróffile of the XR4 receiver board, with "XR4 V1.00" clearly visible, indicating the model and version.
5. Uppsetning og uppsetning
5.1 Raflagnatengingar
The XR4 receiver uses standard CRSF protocol for communication. Connect the receiver to your flight controller or other compatible device using the provided CRSF wire. Ensure correct polarity for power connections (DC 4.5-8.4V).
- 5V: Power input (4.5-8.4V DC)
- GND: Jarðvegur
- TX: CRSF Transmit (connect to RX on flight controller)
- RX: CRSF Receive (connect to TX on flight controller)
- TX2/RX2: Secondary UART port for advanced functionality.
5.2 Uppsetning loftnets
Connect the two dual-band T-antennas to the IPEX-1 connectors on the receiver board. Position the antennas at a 90-degree angle to each other for optimal signal diversity. Use the provided heat-shrinkable tubes to secure and protect the antenna connections.
Þessi mynd sýnir hornrétt view of the XR4 receiver board, highlighting the IPEX-1 antenna connectors and the soldering pads for power and CRSF communication.
6. Notkunarleiðbeiningar
6.1 Binding Procedure (ExpressLRS)
The XR4 receiver comes pre-installed with ExpressLRS v3.5.1 firmware. To bind the receiver to your ExpressLRS transmitter module, follow these general steps:
- Ensure your transmitter module is running a compatible ExpressLRS firmware version.
- Power on the receiver. It will enter binding mode if it does not find a valid link. The LED on the receiver will typically flash rapidly.
- On your ExpressLRS transmitter, initiate the binding process. This is usually done via the Lua script or a dedicated bind button/menu option.
- Once bound, the receiver's LED will turn solid, indicating a successful connection.
- If binding fails, ensure your transmitter and receiver have matching ExpressLRS firmware versions and binding phrases (if configured).
6.2 Operating Modes: Gemini and Xrossband (Gem-X)
The XR4 receiver supports various operating modes, leveraging its dual RF circuits:
- Gemini 2.4GHz: Uses two 2.4GHz antennas for dual-frequency operation within the 2.4GHz band.
- Gemini Sub-G 900MHz: Uses two 900MHz antennas for dual-frequency operation within the Sub-G 900MHz band.
- Xrossband (Gem-X): Utilizes one Sub-G 900MHz antenna and one 2.4GHz antenna for dual-band operation, providing enhanced reliability across different frequency ranges.
The specific mode is typically configured via the ExpressLRS Lua script on your transmitter or through the receiver's WebHÍ.
This diagram visually explains the different antenna configurations and packet transmission methods for Gemini 2.4GHz, Gemini Sub-G 900MHz, and Xrossband (Gem-X) dual-band modes.
7. Fastbúnaðaruppfærslur
The XR4 receiver features an integrated Wi-Fi module for convenient firmware updates and configuration. To update the firmware:
- Kveiktu á móttakanum.
- Tengstu við Wi-Fi netkerfi móttakarans úr tölvunni þinni eða snjalltæki. Netheitið er venjulega „ExpressLRS RX“ og síðan einkvæmt auðkenni.
- Opna a web vafra og flettu að http://10.0.0.1.
- Notaðu WebUI to flash new firmware or adjust settings. Refer to the official ExpressLRS documentation for detailed instructions on firmware flashing.
8. Viðhald
The XR4 receiver requires minimal maintenance. Keep the device clean and free from dust and moisture. Regularly inspect antenna connections for damage. Ensure proper heat dissipation if operating in enclosed spaces.
9. Bilanagreining
- No Link/LED Flashing:
- Gakktu úr skugga um að móttakarinn sé rétt knúinn (4.5-8.4V).
- Verify the transmitter module is powered on and transmitting.
- Check if the receiver is in binding mode (rapid LED flash). If not, re-initiate binding.
- Confirm that the transmitter and receiver are running compatible ExpressLRS firmware versions.
- Check for correct binding phrase if one is set.
- Léleg drægni/merkisgæði:
- Inspect antennas for damage or improper connection.
- Ensure antennas are positioned optimally (e.g., 90 degrees to each other).
- Check for sources of interference near the receiver or antennas.
- Verify the selected operating mode (Gemini/Xrossband) is appropriate for your setup.
- Móttakari svarar ekki:
- Check all wiring connections (power, ground, CRSF TX/RX).
- Ensure the flight controller or connected device is configured correctly for CRSF protocol.
- Attempt a firmware re-flash if the receiver is unresponsive.
10. Öryggisupplýsingar
- Always ensure correct power polarity before connecting the receiver. Incorrect wiring can cause permanent damage.
- Operate RC equipment responsibly and within legal limits.
- Keep the receiver away from water, moisture, and extreme temperatures.
- Do not attempt to modify the receiver's hardware beyond specified connection points.
- Gakktu úr skugga um rétta loftræstingu til að koma í veg fyrir ofhitnun.
11. Ábyrgð og stuðningur
Fyrir upplýsingar um ábyrgð og tæknilega aðstoð, vinsamlegast vísið til opinberu RADIOMASTER websíðuna eða hafið samband við viðurkenndan söluaðila. Geymið kaupkvittunina vegna ábyrgðarkröfu.
