HP-71B Card Reader Failure

[Dave Frederickson]

(03-06-2016 10:11 PM)Geoff Quickfall Wrote:  Didn't tape recorder heads need to be demagnitized on occasion?

Audio tape heads required periodic degaussing. Digital tape heads not so much. I still use my Realistic 44-232 Bulk Tape Eraser which can be found for $20 on eBay. It works on floppy discs and CRT screens, too.

Even submarines and aircraft carriers need to be demagnetized.
https://en.wikipedia.org/wiki/Deperming

Dave