I became a HAM radio operator about a year ago and the bug to be connected as often as possible struck quickly. Love it or hate it, FT8 got me linked worldwide very fast and I was constantly on my radio hoping to get that next distant country. However, I quickly realized my setup often had me in another room away from family and they were dragging their feet on getting their own licenses to join me. I needed a way to control my radio in the garage from the sofa with everyone else. Fortunately, connecting a Raspberry Pi to a HAM radio is very easy and allows getting remote access to the wsjtx interface very easy.

But one little annoyance I could not seem to get past was the need to still walk out to the garage just to push a button for the radio's tuner. Throughout the day as moisture and temperature conditions change, so does the SWR on your antenna so it's handy to periodically activate the radio's autotuner. Fortunately, the rigctl software does allow activating the tuner from the Linux command line which means as long as I could remote into the Raspberry Pi connected to my radio, I could "push" the button without pushing the button.

The following example shows how to perform this task on an ICOM-7300, but the rigctl software makes it generic to all supported radios.

As a first example, you can interactively twiddle with various features of the radio to include the tuner. Simply execute the appropriate rigctl options to open the interactive interface. The -m 3073 selects the IC-7300, the -r /dev/ttyUSB0 selects the interface, the -s 115200 selects the baud rate, and lastly the -v makes it more verbose.

rigctl -m 3073 -r /dev/ttyUSB0 -s 115200 -v

At the "Rig command:" prompt, check the status of the radio's autotuner with the "u TUNER" command to use the software's get_func feature. The system will return a value of 0 or 1 indicating whether the feature is currently turned off or on, respectively. If it's off, use the "U TUNER 1" command for the software's set_func feature to turn it on.

Rig command: u TUNER
Func Status: 0

Rig command: U TUNER 1

Rig command: u TUNER
Func Status: 1

Rig command: quit

While still in the interactive mode, it's easy to trigger the autotuner using the "G TUNE" to use the software's vfo_op feature. Even though there is no output, it's effectively the same as pressing the button directly on the radio.

Rig command: G TUNE

Rig command: quit

There is no need to do this interactively. Simply create a text file containing the commands you need to run and give it a name like autotuner.txt.

echo -e 'U TUNER 1\nG TUNE\n' > autotuner.txt

Then, it's possible to just feed that text file to rigctl and it will run them.

rigctl -m 3073 -r /dev/ttyUSB0 -s 115200 -v - < autotuner.txt

Add it to a cronjob every hour and your antenna will stay nice and tuned while you keep earning family points for not being isolated with your gear. Simply add this line to the end of the crontab for it to run five minutes after the top of every four hours. Why four hours? Tuning the antenna turns on the front display so if you perform the action too frequently, the display will stay on and eventually burn in.

5 */4 * * * rigctl -m 3073 -r /dev/ttyUSB0 -s 115200 -v - < autotuner.txt