At 12.38 2005.05.08 -0400, you wrote:
>> A schematic of my amplifier can be found at:
>> http://www.rocklizard.org/webdownloads/difamp.bmp. This is the *exact*
>> circuit that I am testing. 
>
>> The inputs are fed from 2 adjustable voltage dividers.
>
>This may be your problem. If you are create resistor based voltage dividers
>then the impeadance of the resistors could be impacting your circuit.
>
>To ensure you have low impeadance voltages sources stick a couple of
>opamp based voltage followers in front of your inputs. Something like:
>
>http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/opampvar2.html
>
>The voltage followers will drive the inputs hard, giving you more
>accurate measurements.

At this point I think he better use an instrumentation amp rather than
3 opamps, at least to get more "integration".


>
>BAJ
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