[600MRG] ground

[Bill Cromwell]

Hi Larry,

On my mail client your post appears just after Rudy's post. This reply 
appears to be in part a response to his post.

You may have missed the part about the trees. You definitely missed the 
part about his lot size. Your radials are each 100 feet long. The radial 
field then is a little over 200 feet. Can you see from simple arithmetic 
that is not going to work for those of us who have lots smaller than 200 
feet?

If you have a dense, large radial field your antenna no doubt ignores 
whatever is on the other side. The rest of us make do with whatever we 
can get to work for us. I wonder how large the trees are on top of that 
basalt 30 inches down.

Does this help?

73,

Bill  KU8H



On 02/07/2015 10:45 AM, Larry wrote:
> OK, what am I missing here?
>
> My 630 meter vertical antenna system shows no measurable difference in 
> feed point impedance between bone dry dirt and soggy wet dirt.
>
> For that matter neither does my 160 meter vertical.
>
> My dirt is composed of volcanic ash, sand, and rock. The so called top 
> soil averages 30 inches deep over cliche and basalt. It is so bad 
> during summer that electric fences are no longer effective unless the 
> pasture is irrigated!
>
> The 160 vertical is over a radial system composed of 82x 100 foot 
> symmetrically positioned buried wires in a clear 1.5 acre area. I. E. 
> no trees, no towers, no houses, etc.
>
> The 630 meter vertical is over 16x 25 foot buried wires but the area 
> is more cluttered with nearby conductive objects like metal buildings 
> and towers.
>
> So can anybody tell me why I NEVER see variations in feedpoint 
> impedance due to ground changes on ANY vertical antenna system I have 
> used?
>
> 73,
>
> Larry - W7IUV / WH2XGP