@th In RTTY that's sometimes known as '3rd shift cyrillic' - which when you see a mechanical arrangement like that makes so much sense; on 5 bit baudot you need to send a character or number shift character, so you'd now add a 3rd shift for the other language. I'd love to understand how the mechanics knew when to send the shift character.
@th Yeh, I guess so (like it's neighbouring letter shift key); still teletype electromechanics always amazes me.