Help with remote controlling JRK 21v3

Hi all.
I’m a bit new to Remote Control I’m afraid.
I’m building a remote controlled full size R2D2 and it was suggested I purchase the JRK 21v3 to control the pitman motor for the dome rotation, which just basically is a 12v motor that draws about 1 amp or so, and spins in either direction when your reverse the polarity of the power and ground wire.

so… I’ve got my JRK 21v3 but I’m not really sure what is the best remote control transmitter and receiver to use.
eventually I’m hoping to control more than just the rotation of the dome, as I intend fitting motors to the feet to be able to drive him around. I won’t be controlling millions or servos for opening doors or anything though.

Can anyone suggest a good starting point for me, or even what would be a good transmitter/receiver to purchase… and possibly also how to connect the receiver to the controller?

I am doing a load of research all the time, but I just don’t want to make assumptions early on and get the wrong kit.


Hi Glyn,

We do not have a specific RC transmitter and receiver pair to recommend for use with the jrk. Any receiver that outputs standard RC hobby servo pulses should work fine, so you would want to choose one based on your other requirements. Have you seen this blog post about using the jrk to control an R2D2 dome? You might find some of the information there to be useful.

Connecting an RC receiver to the JRK is fairly straightforward. You can find a video here that shows the jrk being controlled by RC servo pulses at :52 into the video.

Have you determined how you are going to measure the dome’s rotation angle?


Thanks for the info Aaron, and the links. Very useful! the connection on the JRK to the remote control receiver was where I’d sort of worked out where the controller would go.
The bit confusing me now is how to connect to the pitman motor.
I’m happy to just have the dome spinning left and right under remote control, so I’m not bothered at this stage whether it can centre itself of anything… just rotate left and right.
I thought I would just use the ‘A’ and ‘B’ powered motor outputs, which I assume would reverse direction depending on the pulses received from the RC receiver.
However, on the video it shows another 3 wires going into the auxiliary output or the feedback input (as well as the +5v and GND)… I can’t see which one. input or output it’s connected to though. Do I actually need the motor connected here somehow, or do I need some other speed controller after the JRK unit?
the motor I’m using only has two wires which you switch polarity to spin in either direction.

Thanks for your help. sorry if this is basic stuff to you, but I’m new to this! :slight_smile:


Hello, Glyn.

I am glad to hear that the links I sent you were helpful. You are correct that the A and B outputs on the jrk will drive your motor in either direction.

To do what you want, plug your jrk into your computer with a USB A to mini-B cable, and configure it with the jrk Configuration Utility. In the configuration utility, set the input mode drop-down box to pulse-width. Also, under the feedback tab, set the feedback mode to none. After you connect your RC receiver, you might need to calibrate the scaling values.

You can connect your motor to A and B and connect one channel of your RC receiver to the jrk. The signal line should go to RX, and the power lines to +5V and GND (the +5V output will be powering the receiver). Lastly, connect your power source to VIN and GND, and you should be able to move your motor, assuming that your RC setup is functioning correctly.

For information about using the jrk Configuration Utility, consult the jrk’s user’s guide.