Yes I remember tele printers in the 1960s and I had to work with telex machines in the 1980s.
When I took the job, there was a really old machine that could not save text, so, if the message didn't go first time - and as most of them were going overseas, many didn't, our poor secretary/telex operator had to retype it every time. Sometimes she was there until 9.00pm sending just one urgent fax.
I soon changed that. We got an uptodate one that saved text and could be set to automatically try to send a text every 15 minutes for about 6 hours.
The secretary was not grateful, she thought I was deskilling her and took great pride in her willingness to stay late at night to send telex's!