Matek mLRS MAVLink 868/900MHz Receiver, mR900-30

Unlock reliable long-range communication with the Matek mR900-30 MAVLink Long Range System, designed for those who need precision and power in their UAV or telemetry setup. Operating on the 900 MHz LoRa band, this receiver offers a powerful 30 dBm RF output, ensuring consistent transmission over extended distances. With MAVLink firmware onboard and full compatibility with other LoRa chip SX126x systems, like the mR900-22, you can stay connected with confidence.

Note: This unit is not compatible with ELRS 900MHz or FrSky R9 series using the SX127x chip. Compatibility matters!

Key Features:

• 30 dBm RF Power: 1000mW of power for long-range connectivity.
• LoRa SX1262 Chip with TCXO: Robust performance on the 900 MHz band (868 MHz for EU, 915 MHz for FCC).
• Bi-Directional Serial MAVLink: Ensures smooth communication between devices.
• Multiple TX Options: Supports CRSF or SBUS for versatile RC outputs.
• Compact Design: PCB measures only 29x21mm, weighing just 5.3g with antenna.
• Durable Build: Includes a heatsink for optimal thermal management under high RF power.

Specifications

• STM32G431KB,  mLRS firmware
• LoRa SX1262 with TCXO
• PA/LNA SE2435L
• RF Frequency: 900MHz (868MHz, 915MHz FCC)
• 915MHz RF power: 21dBm(min) / 22dBm / 24dBm / 27dBm / 30dBm(1000mW)
• 868MHz RF power: 24dBm(min) / 24dBm / 24dBm / 27dBm / 30dBm(1000mW)
• Antenna connector: IPEX MHF-1
• TX1/RX1: Bi-directional Serial MAVLink
• TX2: RC out(CRSF or SBUS)
• one buttom for DFU mode and Bind

• Power supply: 4.5-13V DC @ “V” Pad
• Power dissipation:  Average 340mA/Peak 850mA@5V IN(31Hz, 30dbm)
• PCB Size: 29x21mm
• Weight: 5.3g w/ antenna

• Packing:
  • 1x mR900-30
  • 1x IPEX MHF1 dipole antenna. 8cm
  • 1x Heatsink 20*20*6mm

LED Status

• [Red flashing 2Hz], not connected to transmitter
• [Green flashing 1Hz], connected to transmitter
• [Red and Green alternately ], Binding mode enabled

Binding

• After powering on,  press the bind button (for ca. 4 seconds) on the receiver. When in bind mode, the green and red LEDs will blink alternatively with ca 2.5 Hz.
• https://github.com/olliw42/mLRS-docu/blob/master/docs/BINDING.md

Firmware

• mLRS  https://github.com/olliw42/mLRS/tree/main/firmware/pre-release-stm32
• Targets:
  • RX Receiver: rx-matek-mr900-30-g431kb
  • TX module mode: tx-matek-mr900-30-g431kb-default
  • TX SiKtelem mode: tx-matek-mr900-30-g431kb-siktelem

Tips

• mLRS Github  & Documentation
• mLRS Discord
• mLRS Facebook group
• If set RF power >=500mW, It is recommended to attach the heatsink to the bottom side of PCB. The gaps between fins can be used for mounting with M3 screws
• MATEKSYS mLRS 900MHz series are NOT compatible with ELRS 900MHz & Frsky R9 series using the SX127x. They will not bind with each other.

Routing and Settings

Use mR24-30 as a TX module : tx-matek-mr900-30-g431kb-default-xxx

Use mR24-30 as a TX in SiKTelem mode : tx-matek-mr900-30-g431kb-siktelem-xxx

Modes and Link Rates

Firmware Flashing

Download STM32CubeProgrammer from ST website

• https://www.st.com/en/development-tools/stm32cubeprog.html

mLRS firmware:

• https://github.com/olliw42/mLRS/tree/main/firmware/pre-release-stm32
• Targets:
  • RX Receiver: rx-matek-mr900-30-g431kb
  • TX module mode: tx-matek-mr900-30-g431kb-default
  • TX SiKtelem mode: tx-matek-mr900-30-g431kb-siktelem

Make sure DFU driver has been installed. Check out “Install DFU Drivers” in this page

Connect the Receiver USB to computer while holding the boot button in.

1. Select USB
2. USB1 and click Refresh
3. Connect
4. select “Erasing & Programming”
5. Tick all sectors and click “erase selected sectors”
6. Browse firmware (hex or bin file) related to the hardware.
7. Click “Start Programming”
8. After programming, unplug USB and plug USB back in. If red LED blinks at 2Hz, the receiver is waiting for connecting with transmitter.

COM/CLI Commands

• Install serial_port_utility
• Firmware tx-matek-mr900-30-g431kb-default,  USB = COM/CLI, connect USB directly to computer, install STM VCP driver,  select STM32 COM port
• Firmware tx-matek-mr900-30-g431kb-siktelem, LT1/LR1 = COM/CLI,  connect USB-TTL module to LT1/LR1, select USB-TTL COM port
• more CLI commands details.