[getting old punched cards read]

From: James Willing <jimw_at_agora.rdrop.com>
Date: Mon Apr 20 23:55:54 1998

At 12:34 AM 4/21/98 -0400, Allison wrote:
>Ah gads you guys do it the hard way. Take a stepper from something and
>put a roller on it with a diameter such that one step will move the card
>forward one column. Then all you need is one rows worth of
>phototransistors. I forget the punched card orgainization but a parallel
>port (printer) off a PC should be enough bits.


>Oh the only difference with hole vs mark sense is transmittance or
>reflective sensing.

Ummm... I may wish to debate that just a tad...

Its been a rare mark sense card that I've seen to stuff 80 colums of data
in a 'standard' tab card form factor. Usually more like 36-40 to allow for
the timing marks and the nominally sloppy filling in of the infamous


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Received on Mon Apr 20 1998 - 23:55:54 BST

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