Concerning my earlier post concerning instrumentation amps or differential
ADCs, I feel I should mention
after reading Dwayne's post I rethought my assumption that these signals
are all loosely referenced to some theoretical "ground", your
problem was just that there was excessive noise floating around on the
power ground for the circuit that you didn't want
messing up your readings or coupling back into the signals being sensed...

If that isn't the case, pretty much everything I said is meaningless drivel
and just ignore it...

ND Holmes
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 Nathan D. Holmes   maverick@drgw.net, ndholmes@iastate.edu
   122 Shepard #3  Box 328  Gilbert, IA 50105  Iowa State University - EE
   http://www.drgw.net/~maverick   PH: 515-663-9368
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