I picked two of these TTYs up at a surplus sale just for cool factor, the switches are just a bonus. Upon pulling a key I found an odd white slider. Hit up the wiki to find it's a USw LXBW02 switch with a white slider.
The switches are the linear version and fairly heavy, MX Blacks feel lighter. They aren't the smoothest either but they aren't terrible, certainly not the worst I've used.
Redmaus wrote: Are those cups on top for a telephone?
They are. These here have both 6P2C (aka phone line) or the acoustic coupler on top for portable use. They can run on 8x NiMH batteries as well as 9VDC input.
Usually these are nice “vintage” MX black switches as well. Some of them are Alps SKFL switches with funky Alps–MX stem adapters, cf. https://geekhack.org/index.php?topic=49639.0
interesting! I have a few (three) of the at&t ones with cherry profile keycaps and MX blacks. I also know they used alps switches on some (and one PCB accepts alps or cherry switches if I recall correctly)
I plan to string some telephone wire between them and send messages to myself.