Item 1394 Jrk21v3

I want to use the Jrk21v3 to control a linear actuator over PWM. I am using a Raspberry Pi 3b+ with an Adafruit Servo/PWM hat:

The 3 pin connectors off of the Pi PWM hat provide Ground, 5v out, and 3.3 volt logic level out.
I noticed on the pin out of the Jrk21v3, that the 5volt pin says (regulated output). Does that mean it is expecting regulated output or it is providing regulated output on that pin? As the Adafruit board sends 5v. Any idea if these 2 products can be connected in this way?

Thanks in advance,

There is a linear regulator on the board that is powered by VIN. You can read more about the pin in the Module Pinout and Components section of the Jrk user’s guide.

If your servo HAT is powered from the Raspberry Pi, then it should be possible for the Jrk to receive signals from it by connecting the signal wire and a common ground (so long as you have also connected VIN and GND to a power source suitable for running your attached motor). The RC input on the Jrks will work with RC pulses as low as 2V, so a 3.3V logic out from your controller should be OK.

By the way, it is also possible to send the Jrk commands using I2C or TTL serial ports on a Raspberry Pi, though you would also need an inexpensive logic level shifter for most connection schemes using those interfaces. It is also possible to connect the Jrk to one of the Raspberry Pi’s USB ports and send it commands.


Hi Nathan,
Thank you for your reply. I am running 3 Jrks controlling linear actuators, plus 2 other motor controllers. I had thought of the USB option, but only have 1 USB port free. I wasn’t certain how well the communication would work over a USB hub. I have 8 sockets open on the servo hat. The servo HAT will be running off of it’s own 5v, 5a power supply.

So I just need 2 wires for each Jrk from the servo HAT (Signal to RX pin on Jrk, and ground to ground pin on Jrk)? I have a 24v power supply that will go to the screw down VIN on the Jrk and screw down ground connector. Is that correct?

Thank you again for all your help,

Yes, it sounds like making only those two connections should work for your system.