HP-71B Card Reader Failure

[Geoff Quickfall]

Yep, these are buggy.

I have two, one reads and writes 90% of the time, the other is hit and miss. I did some numbers on the second one an it was around 30%.

Used the cleaning card, used deoxit on the contacts. Maybe the reader head is magnetized? I have a demagnitizer but have not tried it on the buggy one.

Didn't tape recorder heads need to be demagnitized on occasion?

Geoff