Remember the government surplus auction a couple of months ago? Gerry Block won a rack mount 28KSR still in the box. 
https://www.navy-radio.com/tty/ugc51.htm

And he picked up the TT-333 multi-TD tape relay unit for me. 
https://www.navy-radio.com/tty/28-transmitter.htm#tt333

Are we having fun? You bet!

Nick England K4NYW
www.navy-radio.com