HP Forum Archive 11

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HP67 Card Reader not writing Message #1 Posted by Gene R. DiResta on 21 Mar 2003, 9:14 a.m. My card reader reads OK but generates an error on writing. Earlier this month, I received input from D. Smith and T. Duel. Thank you all for your suggestions. I finally got around to trying their suggestions, i.e. cleaning contacts and tightening screws - no change. I read recent message from owner with card reader problem; capacitor change was suggested. My reader has the three tubular capacitors on its card. Would replacing them work for me ? If so, what type and values are these caps ?

Re: HP67 Card Reader not writing Message #2 Posted by David Smith on 21 Mar 2003, 5:20 p.m., in response to message #1 by Gene R. DiResta I don't think that the caps are your problem. The one that goes bad only affects reading. My guess is still one of the reader leaf switch contacts. Trace the pads on the back of the keyboard where the gold leaf switches touch to the pins on the end of the keyboard. Use an ohm meter or beeper to measure continuity to ground. As you manually insert and remove a card, the three swicthes should close and open in sequence. My bet is that the write protect switch is not adjusted properly.

Re: HP67 Card Reader not writing Message #3 Posted by Gene R. DiResta on 27 Mar 2003, 2:03 p.m., in response to message #2 by David Smith I opened the calculator and identified the leaf switch contact pads you describe. Two of the pads go to pins at the end of the keyboard; one does not. It doesn't seem to connect to any trace. How is this tested?

Re: HP67 Card Reader not writing Message #4 Posted by David Smith on 27 Mar 2003, 6:18 p.m., in response to message #3 by Gene R. DiResta I think there are actually four pads, one is not used (or is ground). Three of them definitely go the the pins to the CPU card.

Re: HP67 Card Reader not writing Message #5 Posted by Gene R. DiResta on 31 Mar 2003, 5:08 p.m., in response to message #4 by David Smith I repaired the problem by putting a slight upward bend on the leaf switch closest to the display LEDs. While your diagnosis was correct, cleaning and tightening the retaining screws didn't work. Contact was never made when the card was inserted. Imposing a slight upward bend on the contact ensured a solid contact between pad and switch resolving the write problem. Thank you all for your very valuable help.

Re: HP67 Card Reader not writing Message #6 Posted by David Smith on 31 Mar 2003, 6:10 p.m., in response to message #5 by Gene R. DiResta The "retaining" screws are actually the switch adjustment screws. They raise and lower those nasty little gold leaf switch. Sometimes the switches cannot be adjusted all the way with the screws and you have to resort to bending the gold fingers (and usually much cursing ensues). The other problem you run into is the adjustments to one switch can affect the others. That is why HP changed the design in the HP41 reader.

Re: HP67 Card Reader not writing Message #7 Posted by Jack on 6 Apr 2003, 1:04 a.m., in response to message #6 by David Smith Where can I get the card reader fixed on HP65 and HP67?

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