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HP-65 - card reader with WB wave noisy - FIXED and RESTORED
05-06-2019, 12:12 AM
Post: #3
RE: HP-65 - car reader WB noisy - Help needed
ciao Tony,
with a pre-recorded card from Standard Pac we have only looked at RA and RB and these are ok,
it's a fact that with the previous keyboard PCB when recording WA was good and WB was noisy,
we are measuring RA, RB, WA and WB both at the Hybrid pins and at the card reader pins.
We have not measured WA and WB when reading, nor with this keyboard nor with the previous
Will do it and report results !
Also we will check all the connections but they seems to be good.
I also don't think that the presence of the anode and cathode drivers should make any difference
however the calculator behaves different when using a keyboard complete or a keyboard driver-less
thanks again !

Edoardo & Alberto
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RE: HP-65 - car reader WB noisy - Help needed - albertofenini - 05-06-2019 12:12 AM

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