Tag Archives: HamRadio

Elecraft KX2 Serial Remote Control using an Arduino Nano – DIY Programming Project with Electronics

Temporary link to video (unreleased) https://youtu.be/SxZHe3Q8yS0

Source Code (Arduino Sketch) – https://drive.google.com/file/d/1vAFgU1TkJCllOeE5bnVJjdRnTjgfB0MQ/view?usp=sharing

Video Script:
Demonstration of what I’ve made! While the KX2 has all of the functions built in, I wanted a way to quickly make changes without having to dig through menus and button combinations. The major reason that I wanted to make a control box is for sending pre-recorded messages in CW and SSB modes. Almost every time I pushed the MSG button I would inadvertently tap the VFO and change my transmit frequency. Then I found some other settings that I would like to have one button push to activate. A couple of settings could take several minutes to set up if they get out of whack, and they can be done in less than a second with the simple push of a button.

For CW, switches 1 through 3 send a pre-recorded CW message. Switch 5 changes the filter settings to a weak signal setting.

The SSB mode has two pre-recorded message switches and settings to reset the AF GAIN, MIC GAIN, and COMPRESSION levels.

The data setting changes a ton of things so you can hook the KX2 to a PC for digital modes. It would take quite some time to make those changes, and this macro sets it up in a matter of seconds.

Finally, all settings have an RF GAIN reduction macro to reduce the gain in the presence of strong signals. As programmed it will reduce the AF GAIN by -3, -5, -10, -20, and -60dB without needing to use the settings menu.

The Anderson Powerpole connectors allow you to use a power supply to power both the Arduino Nano and the radio, if needed.

Construction Segment – The Nuts and Bolts
Shown here is my prototype that I built on a breadboard with the Arduino Uno. Prior to this point I gathered the following materials for my build. If you build the exact model that I did, you’ll need:
1 – Arduino Nano
5 – single pole single throw momentary switches
1 – 3.5mm TRS (stereo) jack
2 – 15A Anderson Powerpoles
About a dozen jumper wires in assorted colors plus two 10AWG wires to loop power from one Powerpole to the other.
I used Q Dope as a temporary adhesive to hold a few things in place
I 3D printed a dual Anderson mount found at Thingiverse
https://www.thingiverse.com/thing:1205771 Anderson PowerPole “Wall” Mounts by VCHSRobotics December 16, 2015
You’ll need an enclosure. I used a box that my guitar pickup was shipped in. 3D printing an enclosure would have been my choice, but I found this while looking for parts, and I liked it!
I gathered some of the parts to do a dry fit on the enclosure to make sure everything could be crammed in there.
I cut the end of the enclosure to install the Powerpoles and power for the Arduino board.
Next I used Scotch tape, a permanent marker, and a pair of calipers to score where I wanted the switch holes to be.
Carefully, I drilled each hole to the size of the panel mount switches.
I used jumper wires with one end cut off to connect the switches to the Arduino Nano. I soldered the power and ground directly to the board. I also soldered three jumpers to the TRS jack for the serial communications to the KX2.
The next step was to program the Arduino Nano and test functionality before “gluing” the jumper wires and placing the Arduino board into the enclosure.
Everything is closed up so alpha testing can commence.
I printed a label, albeit incorrect and not final, to adhere to the front of the remote control box. Buttons 4 and 5 are swapped, and I added more functions after I tested the system live in the field during a #POTA activation.
This image is me alpha testing my design in real time during a real #POTA activation at K-2195 Reed Bingham State Park. I discovered that there were some timing issues that I needed to correct in the software, and I made a list of additional functions that I wanted to add.

Files hosted at http://w1rcp.com

#elecraft #kx2 #pota #arduino #hamradio #amateur #radio #diy #electronics #parks on the #air