By coincidence, I'm in the process of clearing out all my old alarm parts, but I suspect my oldest stuff goes back to, maybe...50's? My oldest panel, is a pristine never-used Ademco Model 110 (like a Model 100, but with a DPDT holding relay instead of the #100's SPDT relay )--I got into the alarm industry in the 70s, but worked with a lot of decades-old equipment. Companies tended to keep making and supporting equipment a lot longer back in those days. I've always guessed the Ademco #100 Panels dated from the 50s, but they might date earlier, as simple as they are.
I also have a couple of old Ademco manuals that covers a broad array of equipment, but again, it may only go back to the '50s or 60s--I have it in storage about an hour's drive away. I glanced at them a couple of days ago, but I didn't think to check the copyright dates; but it's from the era that the #100 Panel was still in use. I doubt it goes all the way back to the pre-1940.
If this later-model stuff is of any interest to you, I'll check further.
PS: If you'll check on this site,
https://www.doityourself.com/forum/electronic-home-security-systems-alarms-devices-87/
you might find some old retired alarm tech who has more to offer than I have.
