At 02:27 PM 4/18/98 -0700, you wrote:
>>
>>If we're talking about hundreds or more, you want an automated solution.
>>There are several companies which have sold modernish punched card
>>readers in the past couple of years with RS-232 interfaces on them;
>>the ones I see most often are Mountain Computer units
[snip]
>>
>>Tim. (shoppa_at_triumf.ca)
>
>So, pray tell... do you know what the difference is between the Mark Sense
>and Punch Card versions of the Mountain Computer reader? (and how to tell
>which is which?)
>
>I have one of these units in my collection, and even though it happily
>accepts the commands which should read punched cards, it always feeds one
>card and then returns an error. So, I would start to think that it is the
>mark sense version, but have never really found any identifiers on it.
>
>jimw_at_agora.rdrop.com
>The Computer Garage - http://www.rdrop.com/~jimw
>Computer Garage Fax - (503) 646-0174
The mark sense readers depend on a series of "timing marks" printed on the
(lower?) edge of the card in order to work and I don't think they're very
good at sensing anything but very dark marks (remember the "special" (#1
lead) pencils you had to use when you filled out those cards in grade school?)
Visit Doug Jones' web site and drop him an email. He's very interested in
punched cards and knows quite a bit about readers, old and new. And while
you're at it, invite him to subscribe to this list. ;)
http://www.cs.uiowa.edu/~jones/cards/index.html
--
David Wollmann |
dwollmann_at_ibmhelp.com | Support for legacy IBM products.
DST ibmhelp.com Technical Support | Data, document and file conversion for IBM
http://www.ibmhelp.com/ | legacy file and media formats.
Received on Sun Apr 19 1998 - 11:26:12 BST