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

[Chuck Guzis]

Date: Fri, 30 Nov 2007 09:52:16 +0100
From: "Arno Kletzander" <Arno_1983 at gmx.de>

> Hmm, like, say, an old cash register? This design is called
> "Volltastaturmaschine" in German (would translate to "complete
> keyboard machine"). They have a latching mechanism that holds in one
> button per column of keys (0-9, representing one digit of a number).
> When a calculation is initiated, the protruding shaft of the latched
> key acts as a stop for a toothed rack or similar device which is used
> to advance the wheels of the accumulator register by as many teeth as
> the corresponding digit says. There are also designs which involve an
> arrangement of levers positioning an intermediate gear along the axis
> of a stepped drum, for example the Badenia VA-17/VARE-17. 

When you mention the big array of keys, I think of a comptometer.  
There's a nice discussion on the web:

http://www2.cruzio.com/~vagabond/ComptHome.html

But the item I'm thinking of was alphanumeric, more like a Teletype.

Cheers,
Chuck