Re: Conductivity sensors


mooseo wrote:

Maybe I'll try running it off a battery to see if that helps.

Yes, that should help.

I've just tried running the circuit off batteries... both 1 battery for
the whole thing, or separate batteries for the multiplexer and the
probe, with the grounds connected,

Why connect the grounds? Even if you have to connect them, use
inductors. The probes seems to be AC shorted.

but the circuit behaves exactly the
same. Individually, each probe registers being submerged by increasing
the voltage drop across the resisstor, but when 2 are submerged in the
same liquid, both have the same drop as if they were not submerged at
all.

any other thoughts? I can try getting some inductors, although it
really doesn't look much like a noise response... more like the two
circuits are inhibiting each other.

Same difference, signal from one probe is just noise for another.


thanks,
mike

.

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