Re: electrical problems with Galvanic Skin Response circuit ( GSR SCL )

Hi Stefan,

thanks for your extensive and quick answer.
I already swapped the input pins 2 and 3 and i also choosed a 25k 
resistor --> Gain=5.
The problem is the mains hum (att. hum.jpg), which is so big, that i 
cant recognize any change in the skin conductance, only little changes 
in the shape of the signal.
With an 1Mohm potentiometer as a replacement for the skin all things are 
fine and i can see a raising DC-Voltage on the oscilloscope.

> I just checked my archive, although I have more than one version of the
> schematic, they all show R25=1K.  You are correct that 1K gives a gain of
> 101.  I scratched out my one and only prototype of this circuit and see
> that I used a 1003 resistor in that position, i.e. a 100K which gives a
> gain of 2.

Does 1003 resistor mean  100k?

Regards
Steffen



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