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HP Forum Archive 15

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41c card reader no drive
Message #1 Posted by Hal on 14 Oct 2005, 8:19 p.m.

Got a good one for y'all.

Just got a card reader for a 41c that pulls cards through when mounted to one calculator, but not when mounted to another one. The card reader functions catalog fine on both calculators. Anybody seen this problem before. I'm thinking I should clean the contacts for expansion bay 4 on the offending calculator with a q-tip and alcohol. Any other ideas appreciated. Thanks, Hal

      
Re: 41c card reader no drive
Message #2 Posted by Tony Duell on 15 Oct 2005, 6:10 a.m.,
in response to message #1 by Hal

Again I am working from memory and don't have the schematic in front of me, but from what I remember, the card reader motor is powered straight off the HP41 battery, not from the logic supply line that's used for all the other chips.

If that contact in Port 4 is dirty/corroded, or if there's a bad connection between the HP41 I/O assembly flexiprint and the keyboard PCB inside the HP41, it's possible that the card reader motor will get no power, but the CAT 2 response will be fine.


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