[TowerTalk] [Bulk] Re: RF Ground is a Myth

[Jim Lux]

On 1/21/15 5:29 AM, Patrick Greenlee wrote:
> I have a triangular tower with legs on 14 ft centers, yes, 14 feet, not
> inches.  I built it with three separate concrete foundations, one per
> leg.  It is currently tilted over so one leg is not touching its
> concrete embedded mechanical connection/mount.
>

>
> Am I missing something?  Will a simple ohm meter test give a reasonable
> measure of Ufer ground quality, sufficient to decide the question of
> whether or not multiple copper clad ground rods need to be installed and
> interconnected?

You need to use an AC source for the measurement: a DC source will cause 
polarization and the reading will be low resistance at first and then 
rise (think as if it were an electrolytic capacitor). The other thing is 
that a typical solid state multimeter uses such low current/voltage that 
you're going to see strange readings.

if you have something like a 12-24V AC transformer around (12.6V 
filament transformer, landscape lighting, bell transformer), you can use 
it: measure voltage and current, and you can go from there.  You can 
even use 110V (with an isolation transformer from the line, please!)




>
> Is it too much of a leap of faith or otherwise to assume the inter-leg
> resistance is an adequate predictor of tower mount to Mother Earth
> conductivity?
>

Nope.. that's pretty much how they do it.