[TowerTalk] ground and conductivity

[Jim Lux]

At 02:36 PM 2/28/2005, Roger K8RI on Tower wrote:



> > At 01:14 PM 2/28/2005, Jim Jones wrote:
> >>If fresh water is bad then how come dx'ing is better when water table is
>
>Fresh water is a long way from pure. It generally contains a lot of salts
>where as distilled or deionized water is highly corrosive as it *wants*
>metals to create those salts.
>
><snip>
> >>
> >> >>From the ARRL Antenna book:
> >> >
> >> >Surface Type              Conductivity (S/m)
>
>Years ago I did a lot of conductivity testing, but it was all in ohms per
>cubic centimeter.
>What's the S?
One's the inverse of the other..
Siemens == mhos
Conductivity is in Siemens/meter (S/m) (or, more commonly for water, 
microsiemens/cm)
Resistivity is in ohm meters  (or, more commonly for water Megohm-cm)

For instance, cartridge deionizers used for process water often have an 
alarm that indicates when resistivity drops below 2 Megohm-cm