[Jack Houpe]

This would all make sense if it is for the "house" alarm. I never tested the system to see if it even worked.

With all the modern stuff we have now for security on the shelf that old system is obsolete but the reason I knew what that was is my door step quit working and I started tracing all the wires out from the momentary switches and one of the switches fed that exact same set up  which was disconnected at the relay, soon as I plugged in the wire a horn went off, not the air horn but a sort of tinny sounding horn. 

We installed a ring door bell, I hard wired it to the 12v control panel in set step area.