Servo control and power from Jrk21v3

I’m currently trying to develop a servo that will control the sails of a model yacht. The gearmotor I purchased is a Pololu metal gearmotor (25mm, 6v/6A stall current, 160 oz-in, 100 rpm). I have also purchased a Jrk 21v3 to control the system.
My RC radio is the cheapo FlySky CT6B. Since the motor is powered from a NiMH 5-cell (6v 2500mah pack) through the VIN and Gnd terminals on the Jrk, do I still need to connect the receiver 5V and Gnd terminals to the Jrk 5V and Gnd(out) terminals along with the signal line from the receiver, or can I only connect the receiver signal line to get operation? The latter three terminals are adjacent on the Jrk. I still need to power two other servos through the receiver, and I am thinking that I should be using the motor battery to power the receiver, and not the Jrk. Also, I am wondering whether or not the pulse width and frequency of the radio is compatible with the Jrk control input. Thanks in advance for your help.

If you do not want to use the 5V pin on the jrk to provide power to your receiver’s power rail, you can leave it disconnected, but you should still connect the ground wire along with the signal. Please note that if you want to power the receiver and servos from the motor power supply, you should check to make sure they will work with your battery voltage. When the jrk is in “Pulse width” mode, it can accept pulse widths from 400 μs to 2600 μs, at a frequency between 10 Hz and 150 Hz, so as long as your radio system’s signals fall between those values, it should be compatible. You can find more information about the “Pulse width” input mode in the “Input Options” section of the jrk user’s guide.


Thanks, Brandon!
I will go ahead and power the receiver from the motor battery. The existing motor battery works OK to power a similar setup, so it should work OK with this new one. Also, I need probably the max duty cycle for about half of the gearmotor’s working time, but still haven’t a good feel for what the other motor parameters need to be. I will check your catalog for any specs on the gearmotor electrical properties, but if there aren’t any listed, do you have any examples of this controller/gearmotor pairing that I can reference? I know - just too lazy to plug and chug!

It is not very clear to me what specs you are asking for. The specifications that we have available for the motor you mentioned are listed on the “Specs” tab of the 99:1 Metal Gearmotor 25Dx54L mm HP product page. If that is not what you are looking for, can you rephrase your question?