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HP 97 card reader - tantalum capacitors
03-09-2018, 05:26 PM (This post was last modified: 03-14-2018 04:33 PM by Dreato.)
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Dreato Offline
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HP 97 card reader - tantalum capacitors
I refurbed an old HP 97 card reader - O rings for drive wheel, superglued the worm gear. Cards fed well, but ALWAYS with errors. I found a post here that mentioned a problem with the tantalum capacitors in the power supply section on the main board. Tantalum caps usually last a long, however, mine were bad. I replaced the 47 uF and 22 uF caps and voila! all worked well. BTW, when I removed the old caps, the leads fell off - these caps were degraded.

Although it's almost always a mechanical issue with the card readers, in this case it was electrical, too.
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HP 97 card reader - tantalum capacitors - Dreato - 03-09-2018 05:26 PM



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