Tags: radio, arduino

Posted: December 20, 2011

Rig control with an Arduino

Every time I come South, I like to bring a little project with me to keep me busy when things get quiet… usually something new that I don’t have much experience with.

My main Amateur radio is an Elecraft K3, which, on the whole, I really enjoy. I have a little homebrew PTT remote, based on a design from G0VGS; essentially two buttons in a small box that plugs into the phono PTT socket on the back of the radio. The controller works really well, except for one minor thing; you have to reach all the way over to the radio to trigger DVR playback. The horror!

Another niggle comes from the K3 itself; DVR playback is cancelled by tapping PTT. I normally use the DVR to call CQ on a 4-second loop; whenever someone comes back to my CQ I need to cancel it in order to stop it transmitting over my caller. However, tapping PTT to cancel playback almost always results in the loss of a single character of the other station’s callsign, with the result that I have to ask them to repeat it. Picky as it sounds, this gets quite irritating after a while.

So, this season’s project is an improved hand-held PTT controller for the K3, based on an Arduino and a Wii nunchuk controller.

The idea is to be able to replicate the momentary and latching PTT functionality of my current controller, while adding the ability to send arbitrary commands to the K3 over its serial connection. This could include commands to trigger and cancel DVR playback, or whatever else you like.

The K3 itself is still making its way down to me on the ship; so all I’ve been able to do so far is a proof-of-concept of interpreting button presses from the controller.