https://www.radioworld.com/tech-and-gear/tech-tips/build-a-diy-silence-monitor Huh... Lots of commercial stations could make use of this, not just hobby stations. One of the reasons that I left television in early 2004 was when the TV station, that I worked at then, went to full automation, several times IŽd come in to dead-air, from the WIN XP based servers locking up, and have to reboot them. At 1st, I was the one getting heat from the dead-air, when I mentioned it. Then, when it happened to other on-air staff, the fix was, not to really fix it, but to get a dead-air alarm, where that unit would then call phones numbers after 5min of on-air silence. (Yeah... I refused to run television that way.) Whelp, looks like a dead-air alarm now can come to the hobbyist-level. Intriguing... (THANKS Boomer!!!!)