Slashed letter O, unslashed letter zero

[Shoppa, Tim]

Paul writes:
> As for the slashed letter O, that's strange.  Certainly it is not CDC practice; the only place I ever ran into this is with IBM, I always considered it an example of IBM doing
> things the weird way.  So it sounds like whoever bought those Teletype machines had them configured in that non-standard way for some reason.  Normal, as far as I know, was slashed digit zero.

Slashed letter O, unslashed zero was by far the most common configuration for Model 33 Teletypes sold/leased through Telex / Dataphone providers. My surplus TTY experience from the early 1980's heavily turned up Model 33's with slashed letter O's.

If you bought a Model 33 through DEC, it almost certainly would've come with a slashed zero and unslashed letter O.

I'm 99% sure I've seen a listing of various Model 33 type-cylinder choices on some greenkeys site. Maybe it's in one of my paper Teletype manuals. Most are at least related to ASCII but there were a handful that were really "out there" (weather symbols, etc.) and seemed to have nothing to do with ASCII except they skipped the first 32 characters as unprintables.

This website has a history of slashing the letter O (and also ticked, center-dotted, etc.) oriented around computing: https://circuitousroot.com/artifice/letters/characters/slashed-o/index.html

Tim N3QE