Just out of total curiosity, I'm trying to identify a system I remember seeing a lot as a kid in the 80s at the Dierbergs and Grandpa Pigeons stores here in St. Louis. I remember the phones looked somewhat similar to the original Nortel SL1 "wedge" phones, with the round Western Electric style handset, and a brown or wood grain faceplate. Pretty sure they were these: https://usedphones.com/phones/electronic-phones/nitsuko-tie-ek-820-12238.html or these: https://usedphones.com/phones/electronic-phones/nitsuko-tie-ek-820-12237.html

I also remember a very distinctive, and loud, warble tone before a PA announcement was made. And 2 digit station numbers.

Anyway, that's about all I remember, just curious. I deal with all IP systems at work everyday, but I have a growing collection of older stuff at home, wouldn't mind adding one of these systems.

Thanks!