> If true, then it would have a resonant length, making a scanner for
> "money" practical.  Hmm.. I wonder if the stripes have different
> dielectric constants, which would make the resonant points different..

I heard, some years ago, that *some* bill changers could be fooled
*some* of the time by a stripe removed from a five spot and taped
or glued to a one into dispensing five dollars worth of quarters.  The
trick was getting the stripe out- required a lot of patience with a
tweezer.

I would estimate that this was 15+ years ago, or so; long enough that
my memory is fuzzed by my youth at the time and I certainly had NO
concept of resonance or how the bill reader might know what I had
inserted.  It might make sense, though- it would be easier to make a
reader that would reliably read the resonance of the strip than to read
the crumpled, drawn-on, defaced bills inserted into the machine.  At
least, 15 years ago it was; now they probably check both.

Mike H.

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