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HP-67 Card Reader became very touchy
11-05-2023, 09:23 PM
Post: #45
teenix Offline
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RE: HP-67 Card Reader became very touchy
I'm guessing the MI input on the sense chip is for Motor Inhibit.

If so, the 2nd 3u3 capacitor is part of a motor inhibit circuit. I guess the motor turns on briefly at switch on or switch off for the 97 and this circuit addition stops that.

It is not used in the 65/67, but is in the 41 card reader module.

cheers

Tony
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RE: HP-67 Card Reader became very touchy - teenix - 11-05-2023 09:23 PM



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