IDing WYSE terminal

Is there a way to tell what type of WYSE terminal one is? I have a broken terminal that I need to figure out what kind it is, so I can connect a PC running emulation (or another terminal) to the system. The terminal itself carries only the name of my phone system (it is the operators terminal for it), but opening it shows a main board marked WYSE. But I can't find anything that says what KIND of wyse. Is there someplace is should be marked? It is possible to tell based on some of the chips? I also see some kind of a daughter card attached to the main board. Are these terminals custom programmable? Is it possible the phone system uses a stock terminal with some kind of custom additions (I sure hope not, but I have that fear, as the keyboard has some phone specific keys like Voice Mail on it... but I was really really hoping they were just regular keys and the system knows that things like "end" really mean enter the Voice Mail system). Anyone have any pointers for me about how to figure out what terminal type this is. Thanks (oh, and it should fit as on topic, since the only date I can find on the unit is a refurb'd sticker marked 1991, so it just had its 10 year B-day... at least since being refurbished, that and the phone system it belongs to was discontinued about 15 years ago) -chris <http://www.mythtech.net>