> At 11:50 AM 10/19/99 -0400, Chris wrote:
> >>From what I can tell, you're suggesting to basically connect one end
> >of the electrode to 2.5V.  I'd then be running current through the
> >electrode and I'm not sure that's a good thing...
>
> One point of voltage reference doesn't make a circuit. It is irrelevant
> what the common point signal voltage is, since the pH electrode is not at
> earth ground, and the common signal voltage is not connected to earth ground.

The problem is, the solution conducts.  (ie. saltwater)  There will
also be other probes that will require different offsets.  I'll have
to stick with the instrumentation amplifier configuration for everything
it appears.

Now I remember why the idea of running current through it bothered me.

Chris