Nevermind, the photos 440k were deemed too large to be sent by the TriEmbed server.
Sorry you will not be able to see them. On Sun, Aug 9, 2020 at 5:38 PM Rodney Radford <[email protected]> wrote: > I forgot to include the photos... > > > On Sun, Aug 9, 2020 at 5:37 PM Rodney Radford <[email protected]> > wrote: > >> One of the passions I have put time in the last few months are collecting >> and learning about old vintage computers. >> >> I currently have: >> * IMSAI S-100 system >> * Sol-20 S-100 system >> * TRS-80 Model 1 and 4p >> * Two Apple IIe systems >> * Kaypro 10 luggable system >> * TI 99/4 >> >> I used to have a much larger collection including >> * Burroughs L5000 (google about that beast) >> * TRS-80 Model 2, 3 and 4 >> * Zerox CP/M system (I think I still have it, but can't find it) >> * Pet Commodore 2001 (loaned to a 'friend' - never got it back) >> * several Apollo systems >> >> While I wish I could have kept all the old systems, it just was not >> possible due to storage space constraints. >> >> Back in highschool, a teacher gave me her old 4-function Singer (yes, the >> sewing machine) calculator. I, of course, took it apart... ;-) >> >> I did keep two parts from the calculator - the keyboard (mechanica >> marvel) and the storage device (a mechanical delay line). >> >> When I first looked inside, I saw the aluminum box with the words read >> amp and write amp on it, and I *knew* I had found core memory. Then I >> opened it and was completely surprised with what I found. It is a >> magnetostrictive delay line memory device - memory was stored by twisting >> the wire at one end, and the twist would propogate through the long coil >> and out at the other end. By varying the direction of the twist, data could >> be stored temporarily, and it was then sent back in again for storage again. >> >> The other item I kept from the calculator was the keyboard. On each >> keypress, the key was decoded with gears and levers that move magnets over >> reed relays - as that was more economical than a simple electronic keyboard >> decoder. >> >> >> Here is a link to information about the calculator (and some info on the >> delay line): >> >> >> https://www.oldcalculatormuseum.com/friden1160.html >> <https://www.oldcalculatormuseum.com/friden1160.html?fbclid=IwAR1jtFCm3O_oRCn_hLop43h5fNOtefDedwSv1hVtzH7vUv_TSvCC4qqGjEs> >> >> >> Photos included of the delay line and keyboard. If we were meeting in >> person Monday, I would have brought them out for show and tell. >> >> I also really enjoyed the virtual vintage computer festival I mentioned >> earlier. Some really good talks on that, and my first of four books I >> ordered arrived today - the ENIAC Technical Reference manual, as written by >> one of the first female programmers on it. >> >> >> PS: If you have any old systems that need a home let me know. I really >> should have grabbed the TRS-80 Model 100 that I brought last year that was >> given to the club, but I let someone else take it (any idea who grabbed it?) >> >> >> Anyway, back to current time where I need to finish up an IoT device for >> work... ;-) >> >> >>
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