> re: alerting telemetry - I'm not finding photos to cite right now, but I've absolutely seen "infrastructure" buildings (here in rural Ohio) with warning annun

> re: alerting telemetry - I'm not finding photos to cite right now, but I've absolutely seen "infrastructure" buildings (here in rural Ohio) with warning annunciators (lights and bells) on their exteriors along with signs reading "If this light is flashing call xxx." It's definitely a viable system for alerting. I can confirm these exist, as growing up my father's phone number was on a some of those signs. Fancy systems would automatically call an answering service, but for smaller ones, he'd get a call (or page, given the era), usually from a neighbor or something. It wasn't limited to rural areas either. I distinctly remember him taking service calls in ultra-wealthy neighborhoods on the weekends. One time, the gentleman who called in let my sister and I watch movies in his personal movie theater while my dad fixed the system.