On Wed, Apr 08, 1998 at 12:21:44AM -0700, Richard Nowak wrote:

> Add another very short sensor rod attached to the end of an insulated rod to
...
> The third probe is used to calibrate out the variation of the rainwater
> conductivity.

Now that is a great idea! Here's another; use a length of coax cable,
with the outer jacket removed, so the braid forms the long rod, and the
inner conductor, exposed only at the bottom, forms the reference electrode.
Just have to make sure the inner conductor is sealed well where it enters the
insulation. A weight attached to the end will hold it vertical.

I think we're getting somewhere here.

The suggestion someone else had about a laser pointer for a beam is
worth considering, except I can't see how to make it invisible - the receiver
could be in a tube, but in the presence of fog the beam would be very visible.
That may not be a big problem, though.

--
Clyde Smith-Stubbs               |            HI-TECH Software
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