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BMK Ultralight RDT Rx module - 0.7g

Regular price £35.99

BMK DT Rx module is the lightest RDT receiver that is designed to use with host timers. It's compatible with most Black or Red Magic timers as well as many more.

The DT receiver is compatible with our BMK B1 transmitters which can be ordered as a bundle or sold separately. Each transmitter has its own unique code and you can connect a transmitter with an unlimited number of receivers.


Package Content:

  • Timer Circuit Board
  • Straight and Right-handed pin headers


It's designed to work with all known host timers(black magic, etc) including the timers that do not support RDT input. 

Mimics the simple button click/interrupt in the delivered mode and is also configurable for 5 different modes including stand-alone servo toggle and logic high-low. 

The current consumption is only 6mA and supports all power sources between 3-15V.

You can also plug a 1S battery into the supply pins and control a DT servo directly if you want to use it independently. 


Working Frequency : 434 MHz
Input Sensitivity : -116dBm
Range : 2750m (calculated typical open field outdoor range)
~500-800m. with B1 Tx units under the general conditions. 
Input Voltage : 3-15v
Output Signal Voltage : High Impedance or Logic Levels(3.3v)
Power Consumption : ~6mA @ Receiving
Low Battery Warning : <3.0v (double flashes instead of single)
Dimensions : 21mm x 10mm x 3mm without mounting ears
Weight : 0.7g (the antenna included)


How To Bind a Receiver?

  • Press and hold the onboard button before plugging the battery.
  • Plug the battery, then release the button
  • The Receiver LED will flash continuously at 5Hz.
  • Click the Transmitter DT Button.
  • The Receiver LED will turn solid RED to show the binding process completed successfully.
  • Remove the battery and plug again to use.

Mode Settings

  • Press and hold the timer button before plugging the battery. (like the binding process above)
  • Plug the battery, then release the button
  • The Receiver LED will flash continuously at 5Hz.
  • Press and hold the button and count the LED blinks for the mode number.
  • Release the button when you reach the desired mode.
  • The LED will fast flash 3 times when saving the timer duration. Then turns to solid RED.
  • Remove the battery and plug again to use.


1- Interrupt Source / Button Emulator (High Impedance- Logic Low)
This is the default RDT Rx mode for all known host timers.

The S-pin of the Rx will be in high impedance mode until the RDT Tx button is pressed. It will switch to Login low for 200mS and return in high impedance mode to mimic a button click or interrupt source. 
Simply plug it into the RDT input and it will work.

2- Logic High-Low
The S-pin is normally LOGIC HIGH, 200mS LOGIC LOW when the RDT Tx button is pressed. This mode can be used for DIY remote control applications.
3- Logic Low-High
The S-pin is normally LOGIC LOW, 200mS LOGIC HIGH when the RDT Tx button is pressed. This mode can be used for DIY remote control applications.
4- Standalone Servo Cycle 
Servo travels from left to right for 2 seconds then returns to the arming position automatically.
5- Standalone Servo Toggle
Servo travels from left to right when the Remote DT button is pressed. It travels back when the button is pressed again and so on. You can cancel the DT operation in mid-air if you are using a pushrod-operated DT system.
6- Standalone Servo Toggle Tri-state
Same as Mode 5 but the servo travels between 3 positions(left-centre-right) by the remote.


Questions and Trouble Shooting

  • The Transmitter LED is blinking fast.
    Replace the battery with a quality CR2032
  • The Transmitter is not working.
    Check the battery / Replace the battery