Mechanical calculators (was: Re: *updating* 8088's)

Arno Kletzander Arno_1983 at
Sun Dec 2 12:18:11 CST 2007

M H Stein <dm561 at> wrote:
> The IBM unit record or Tabulating machines that we've been discussing
> had their roots in the same principles as these calculators, adding 
> machines and cash registers (...)

Thanks for that interesting piece of history! Nice insight into the workings of unit record equipment, a quite fascinating category of data processing in itself.

My contribution however was not targeted at the IBM equipment thread, btw.

"Chuck Guzis" <cclist at> wrote:
> "Roy J. Tellason" <rtellason at> wrote:
> > This stirs a vague recollection of an old mechanical adding machine I 
> > once had,  the kind that had a big rectangular array of buttons instead 
> > of just a "10-key" set of numbers.  I have *no* idea how it stored a 
> > number in there, though.
> (...)
> When you mention the big array of keys, I think of a comptometer.  
> There's a nice discussion on the web:
> But the item I'm thinking of was alphanumeric, more like a Teletype.
> Cheers,
> Chuck

Yes, exactly that is the class of machines I meant. There were similar ones which printed on a platten carriage mounted behind the adding machine body, and some of the latest electromechanical models had a "type box" as a means of commenting the ledgers, invoices - whatever. The letters were assigned as secondary functions to some of the keys and the machine would print those instead of accepting numeric input when it was in a column definded for comments (which was done by sticking pegs into a programming board moving together with the carriage).
Arno Kletzander

GMX FreeMail: 1 GB Postfach, 5 E-Mail-Adressen, 10 Free SMS.
Alle Infos und kostenlose Anmeldung:

More information about the cctech mailing list