"Walter Maxwell" wrote in message
...
Hi Reg,

You've presented a very interesting way of measuring soil characteristics.
When I return to Florida in November I'm going to use your method of
measuring the soil underneath the dipole whose impedances I measured over
the frequency range 14 to 15 MHz at various heights above ground,
including one set of measurements with the dipole lying on the ground.

One of the reasons I offered to distribute the data from my measurements
is to see whether anyone can deduce any soil characteristics from the
changes in impedance with height. The changes are significant. For
example, the terminal impedance with the dipole on the ground runs from
470 + j250 at 14 MHz to 570 + j132 at 15 MHz. The inductive reactance
doesn't become capacitive until the dipole is 2 ft off the ground. In
addition, except at zero height, the resistance component decreases with
height, but for every height the resistance increases with frequency. Do
you think any of the soil characteristics could be determined by such
data?

Would you like a copy of my data, just fer the helovit?

Walt, W2DU

I was working at a company a few years ago, and they built a capacitor of
two plates, about 6" on a side, and 0.25" separation. They measured the
thing on a network analyzer, and then packed the dielectric with potting
soil. Again measuring the results on the network analyzer they were able to
deduce the conductivity and permittivity of the soil. I did not think
potting soil was typical, but still an interesting experiment.

Frank

PS, Walt, I would very much like to receive your experimental dipole pdf.