I volunteer at Cross Rhythms Radio Plymouth from time to time, fixing various bits of kit. I also have the privilege of working with a very talented Y10 computing student. The stage was set for some real world computing fun.....
Over a few week we have built a system that links a raspberry pi to the current Sonifex Silence Detector. Whenever either the studio feed or the backup feed go quiet, the silence detector triggers an alarm. This causes a relay to connect, joining two pins on the rear DIN connector. The pi connects to these and sends a text, stating which feed is down. Really useful real time information!
The system also sends a text once a week to say it's alive, and if a feed goes down and then comes back, reports that all is well once again. This is a bit of an oversimplification of the program to say the least.
The python program with reads the GPIO inputs on the Pi and sends texts via the USB 3G modem is a really neat bit of software (entirely written by the student). Hopefully I'll post the source code here in time, but we forgot to back it up before installing the device in a hard to access spot. For the meantime, here's a photo-
It looks a bit rough and ready but works a treat!