This 'scope clock also uses circle generators rather than vectors to produce well-formed characters. It mentions a Teensy controller so I don't think it's the original made in this way - the first I heard of was too long ago for that. But I don't know if it's an update or a separate design.
https://scopeclock.com/ On Thu, Apr 4, 2024 at 2:59 PM Paul Koning via cctalk <cctalk@classiccmp.org> wrote: > > > > On Apr 3, 2024, at 6:32 PM, Rick Bensene <ri...@bensene.com> wrote: > > > > I wrote: > > > >>> The digits are among the nicest looking digits that I've ever seen > >>> on a CRT display, including those on the CDC scopes as well as IBM >> > console displays. > > > > To which Paul responded: > > > >> I have, somewhere, a copy of a paper that describes analog circuits > > for generating waveforms for digits along the lines you describe. > >> Might have been from MIT, in the 1950s, but right now I can't find > it. > > > >> Found it (on paper): "Generating characters" by Kenneth Perry and > >> Everett Aho, > Electronics, Jan 3, 1958, pp. 72-75. > > > >> Bitsavers has it in the MIT/LincolnLaboratory section: > https://bitsavers.org/pdf/mit/lincolnLaboratory/Perry_and_Aho__Generating_Characters_-_Electronics_19580103.pdf > > > > Very interesting. Here's a link to the patent for the display system > on the Wyle Labs calculator: > > > > > https://patentimages.storage.googleapis.com/17/51/58/89c19cee6c60e2/US3305843.pdf > > > > The concepts are very similar to the paper written up in ELECTRONICS > magazine in early 1958 that you found. Your memory is incredible to have > been able to have this pop into your mind when you read my description of > the way the calculator generates its display. > > > > Thank you for looking up this article! It'll provide some nice > background for the concepts of generating characters this way when I > finally get to documenting the Wyle WS-01/WS-02 calculators in an Old > Calculator Museum exhibit. > > > > I wonder if the inventor of the display system for the calculator (in > fact, the inventor of the entire Wyle Labs calculator architecture) had > read this article at some point prior? > > > > I scanned through the patent for the calculator display system looking > for any reference to the article or any document from MIT relating, and I > couldn't find anything. > > I didn't see any either, and the patent examiners didn't cite any. Then > again, it's amazing how often patent examiners miss relevant prior art. > One example I like to mention is Edwin Armstrong's patent for FM radio, > which doesn't cite an actual earlier US patent, 1,648,402 from 1927, > actually filed 12 years before Armstrong's. Or the prior art centuries > preceding US 6469... > > On the other hand, while the concept is similar the details are rather > different, and the Wyle design is clearly a whole lot simpler. > > > The inventor is still alive, and I have talked to him on the telephone a > couple of times. For his advanced age, he is still quite sharp, and > remembers a lot of the challenges involved with trying to make a > solid-state electronic calculator that would fit on a (large) desktop using > early 1960's technology. > > It would be neat to ask him about that MIT article. > > paul > >
