868MHz band NBFM sub-miniature TX

The MTX3 transmitter module adds a totally new sub-miniature form factor to the existing range of Radiometrix ISM band devices. Using cutting edge integrated RF devices, it offers multi channel, low power narrowband operation in a previously unobtainable size.



  • Conforms to EN 300 220-2 and EN 301 489-3
  • High performance Fractional N (Sigma-Delta) Synthesizer with TCXO
  • Vibration resistant (negligible microphony)
  • Data rates up to 10 kbps for standard module
  • Usable range over 500m (with suitable aerials and matching receiver)
  • Fully screened. Very low profile
  • Feature-rich interface (analogue and digital baseband)
  • Re-programmable via RS232 interface
  • Low power requirements


  • Keyfobs and other hand held terminals
  • Small form factor data loggers
  • Industrial telemetry and telecommand
  • In-building environmental monitoring and control
  • Covert, high-end security devices
  • Unobtrusive fire alarm sensors
  • Heavy vehicle/machinery controls

Technical Summary

  • Operating frequency: 869.2125 and 869.2375MHz -Social alarms(Design will cover 850 – 880MHz)
  • 915MHz band version available
  • Other custom UHF bands
  • 4 parallel channels (also fully controllable via serial port)
  • Transmit power: +10dBm (10mW)
  • Supply range: 3.1-15V (will operate down to 2.9V)
  • Current consumption: 24mA @ 10mW
  • Data bit rate: 10kbps max. (standard module)
  • Serial configuration by inverted RS232 at 3V CMOS level
  • Size: 23 x 12.5 x 7 mm

Please Note Disclaimer:

Lemos International does not assume any responsibility for errors nor any liability arising from the application or use of any sub-assemblies purchased through Lemos International, including fitness for any particular application.

The purchaser must satisfy all relevant FCC and Radio Regulations which applies to their finished product in the country of intended use. These modules transmit and/or receive radio signals and may not function as intended if interference is present.

Downloads & Datasheets

  1. Full Specs PDF


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