Slashed letter O, unslashed letter zero

[Paul Koning]

> On Apr 26, 2022, at 1:25 PM, Shoppa, Tim via cctalk <cctalk at classiccmp.org> wrote:
> 
> 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.

Indeed.  But my first exposure to computers was in Holland, where the Flexowriters certainly didn't come with slashed letter O.  Nor the Selectric console on the Philips PR8000, or the line printer output.  I never ran into a slashed O until I was amazed to see one on some IBM system.

Curious that it would be "the most common configuration" on model 33s.

> 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.

If it has weather symbols, it might be a 6-bit machine.  Up to the 1970s or so, "wire service" links connecting to newspapers to carry AP news and stock market info and the like were normally 6 bit, typesetting machine coding or something rather similar.  But the actual code depended on the service: upper/lower case text for news wire, lots of fractions for stock listings, and clouds and lightning bolts and such stuff for the weather wire.

> 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

Wow, there is a lot of wonderful stuff on that site!  It almost feels like a web page version of Lindsay Publishing, sadly gone now.

	paul