Re: Mag Cards and Card Reader Repair Message #10 Posted by Reinhard Hawel on 6 Oct 2000, 6:37 a.m., in response to message #7 by Mike DAvis
I guess there are better experts on the 41 and 65/67 calculators, but the 71 and 75 cards are physically the same.
They have a timing track preformatted by HP. The 7x card readers have no possibility to format this track. The logical format is the same and if you saved your HP-75 BASIC programs as LIF (Text) files chances are, that you can read them into the 71 and transform them into 71 BASIC programs. Might be, that you have to change some commands slightly...
The hand-pulled concept with timing track had the advantage of higher bit density on the cards.
41 cards had to write the timing signals too, which generally leads to a higher redundancy level.
I'll have to search for the hpjournals describing the card reader technologies for getting the bit densities...
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