[cctalk] Re: IBM Punched Card Equipment

On Sep 4, 2025, at 06:32, Bill Degnan via cctalk <cctalk(a)classiccmp.org> wrote: David, My Operators Guide (to) Electronic Punched Card Accounting Machines put out by IBM in 1951 lists the 513, 514, 519. I agree that the two you're looking for were special units, and it appears not commercially available. To locate the docs you need to track someone down who has documents related to the ENIAC itself. I might try the Hagley Museum in Wilmington, Delaware, sometimes they have rare technical documentation and it might be worth a shot. Bill kennettclassic.com / vintagecomputer.net > On Thu, Sep 4, 2025 at 6:51 AM David Wade via cctalk <cctalk(a)classiccmp.org> > wrote: > > > >> On 03/09/2025 21:48, Brian L. Stuart wrote: >> Apologies in advance to anyone who gets this multiple times. >> I know a number of you are on more that one of these lists. >> >> I'm looking for some information on a couple of the early >> IBM unit record devices, in particular the Type 512A and >> the Type 518. Ideally, I'd like to get the mechanical >> dimensions in enough detail to create a CAD model. > > As I assume you are aware, but perhaps others on here are not, that > these pre-date computing and must come from the era when data processing > involved only punched cards and I feel well before the term "Unit > Record" was coined. Sadly, this seems to be a forgotten era and there is > very little information about it on the web. > >> The background is that I'd like to improve the model that >> I'm using in my ENIAC simulator and I'm involved with a >> school in Arizona that's working on a project to build a >> full-scale model of the ENIAC. There's a letter from >> IBM in the ENIAC archives that suggest the use of the >> 512A and the 518. So I'm pretty sure those are the ones >> they used, but I haven't really been able to find any >> details about them. We've found a fair amount of >> information on the Type 513, and from photographs, the >> punch used on the machine seems similar to the 513, but >> is smaller. > > Looking at the photographs linked from here:- > > https://www.columbia.edu/cu/computinghistory/eniac.html > > in particular > > https://www.columbia.edu/cu/computinghistory/eniac6.jpg > > I think you are correct, but I wonder if the 512A and 518 were > "specials" which is why there is little information on them. > I believe that in Punched Card processing normally you initially punched > cards by hand and any punches without keyboards were some kind of > calculating re-producer. > > So for example on a loan system, you charged interest every 6 months. > For each loan you had a card with the loan amount. > You fed these into a calculating reproducing punch which calculated the > interest and punched a new card with the interest owing on it. (we > actually punched two) > You could use these to produce the interest letters. When the interest > was paid you could use the cards in a tabulator to print a summary of > the days/weeks payments. > After a month the cards you had left could be used to chase payment... > .. when I started work in 1976 one of my first jobs was to replace such > a system with screens.... > > So any punch you used probably had a reader attached and a plug board > that controlled how the cards were copied. The 513 is such a device. So > it has reader, plugboard and a punch. > I feel the devices ENIAC used were simply punches or readers. Looking > through the publicly accessible archives at > > https://www.columbia.edu/cu/computinghistory/ > > its apparent that IBM had already produced custom versions of their > equipment, so it likely that these were specials. > The only other pictures I could find were in this book, 28th page in the > PDF > > > http://www.bitsavers.org/pdf/ibm/punchedCard/Training/IBM_Accounting_Course… > > which shows a reproducing punch so I wonder if that is a 512.. > > >> >> Thanks in advance, >> BLS > I am sorry not to be more helpful > Dave > >