Please join my Facebook group for updates and your questions.

BMK B2 Long Range RDT Transmitter

Regular price £55.00

    A powerful version of the B1 Transmitter for all 434MHz BMK Remote DT receivers. 

    Its output power is 9 times greater than the B1, but that's not the only difference between the B1 and B2 units. The B2 unit uses a precision high-quality Tx module and a proprietary algorithm to compensate for small frequency differences between receivers.

    Each digital transmitter has its own transmission code and operates with an onboard Lithium Polymer battery.
    The receivers learn the code during the binding process, so a single Transmitter is enough for an unlimited number of receivers.

    THE B1xxxxx TX CODE

    If you already have a B1 transmitter and connected receivers, you can send me your B1 code and I will program your B2 for the same code. So you can use both transmitters together without re-bind your receivers. Otherwise, every B2 transmitter has its own unique code.

    B1 RDT code


    You will receive a 3D-printed ring together with your B2 transmitter.
    This is an optional part and you can glue it around the button if you are concerned about accidental button clicks. 
    Any contact adhesive or CA glue will work. 


    Receivers may deviate from the centre frequency due to component quality, extreme temperatures, the antenna or just near metal objects. 

    The B2 Tx will transmit 3 data packages at the centre frequency in a row then you have pressed the button. This is generally enough for DT if there is no interference or frequency drift.
    You can press and hold the button if required.
    This time the Tx will wait for 0.3 seconds and transmit -+5khz offset signals to compensate for the possible frequency drift of the receiver. 
    Press and hold the button until the DT is activated.  The transmitter will try the offset and the centre frequencies continuously.

    B2 RCDT Spectrum

    *The maximum transmission time is 30 seconds. Then you must release the button and press it again to continue.


    The battery will be enough for ~10.000 DT and you will hear a different Tx tone and additional 4 tones between the transmissions when the battery is low.  The battery will be still enough for ~200 DT  when it's low so you can complete the day without charging. 

    The device battery can be charged directly with a standard USB micro cable(not included) The charge LED goes OFF when the battery is fully charged.  Generally, it takes ~1.5 hours if it's completely empty. 
    * Li-Po batteries must be stored with less than ~%80 charge level.  Please don't charge your device after a flight day if it's not required. 

    Package Content:

    • a B2 Tx 
    • an Antenna
    • a Ring


    • Weight: 50g
    • Dimensions: 75mm x 50 mm x 20mm
    • Maximum battery life: ~1.5 hours continuous press/ 10.000 DT
    • Low Battery Warning: <3.3v (multiple flashes & alternating buzzer tones)


    Questions and Trouble Shooting

    • The Transmitter LED is blinking fast and beeping with alternating tones
      Charge the battery.
    • The Transmitter is not working, no life sign
      Possible battery or button failure. Plug the USB cable into the charge port and press the button, It's a button failure if the device is still not working. Contact me.