I’ve long hoped for a way to make it easier to change DMR talkgroups. I use a DV4mini and software installed on a Raspberry Pi 3 with a touch screen display. Wouldn’t it be nice if I could key in a Brandmeister extended talkgroup (XTG) number directly on the RPi, rather than use an Android app or a web browser? The now defunct DV4MF2 dashboard was a step in the right direction with XTG support, but its talkgroup list is now hopelessly out of date. Wireless Holding’s version of the dashboard allows connection to Brandmeister reflectors and to TG 4999, but doesn’t directly provide access to the XTGs.
So in the true Amateur Radio spirit, I built my own solution. Long ago, I made my living as a software developer. It was so long ago that we were called computer programmers. Nonetheless, I did some research and found that GTK provides support that I could use from within a Python program to create windows, buttons and so on in a Linux GUI environment.
To further date myself, most Linux based programming that I’ve done in the past 20 years has been in Perl or Bash. I have recently gotten involved in implementing the Open Source Fail2ban host IPS system, which uses Python regular expressions. I have become slightly proficient with regexes, but knowing how to use them to match text in logs wasn’t going to help me.
Thankfully, a fellow named Kris Occhipinti put together a treasure trove of programming instruction videos, some of them covering Python, GTK, and specifically how to create a keypad. His intent in some of the videos was to create an app for spoofing caller id, but I could borrow what I needed.
What I came up with is a Python/GTK app that opens two windows. One window is a dialer keypad and the other window is a memory present keypad. A Brandmeister TGID can be keyed in from a keyboard, pressed on a touchscreen, clicked with a mouse…or you can just use a preset with a label like “USA” or “Tri State” instead of a number. The app makes use of the published Brandmeister API, which is very simple, uses HTTP and returns data in JSON format. Python very nimbly handles it all.
If you’re a licensed amateur radio operator, have a DV4mini, and are Linux proficient, please give it a try and leave your feedback below.