It's good to see all here that value the ingenuity and creativity of the past, and more importantly, enjoy it, and share. I'm new to this list after very recently reintroducing myself to the TTY world. My first experience was long ago in the mid 1960's with an M15. In the late 1970's I dragged home from my workplace a fully loaded ASR33 with the embedded phone modem, along with boxes of paper and tape. It had been abandoned in place by NJ-Bell. I did not start to work with it until a couple years later, after a move, building a homebrew solid state TU unit. Then, little did I know, hams were only working with 5-bit. At the time there were few home computers or a foreseeable need, so sadly and to create space, the machine went to the curb.

So this year after almost 40, I picked up some pieces and parts thanks to Bob K1QVX and Jim W2JC to recreate/relive/cherish the past and restore to life a M19 and M15 pair. I'm still scrounging for parts, but have made good progress in the last month or so. My M15 has been cleanud up, is printing and is waiting for proper lube and a few keytops. The cabinet will need some paint, glass, etc. My M19 table has been scraped of loose rust, spot sanded and Por-15 primed and painted. The Thyratron P.S. unit sits under a work bench for now and will need some careful study on its needs. I've built up what I call a "Table in a Box" to provide loop and DC needed for bench repair for the M19 printer, KB and punch. There's no room in the barn for the full table!  The box could be used in place of the full P.S. if needed! I have some progress pictures on a webpage.
 
https://w1an.com/tty-project

The unit uses a conventional full wave bridge with choke input filtering, a 10 ohm series resistor for monitoring the loop current and receptacles for the printer and punch DC. (I have some extra Nema receptacles if someone needs them.)

Hope this is of interest!
73, John W1AN