On Sunday, March 8, 2015 at 6:21:06 PM UTC-5, Brian Reay wrote:

The ground is good here,

With respect, the difference in local ground is rather over stated.

Maybe so, but not really by me. :|

Taking the US as an example, the conductivity ranges from 0.5mS to 30mS,
which sounds a lot. However, compared to sea water, 5000mS, it is all
rather poor.

Sure. It's rated at 30mS here, which was why I said it was "good".
And I'm about 55-60 miles from the Gulf of Mexico. I've run mobile from the
beach, one time actually backing up to the water and running ground wires
into the ocean. Needless to say, my 14 ft tall mobile whip was browning
the food quite nicely on that occasion. On the Ford truck it was on,
it does pretty well even over poor ground, but it really got with the
program down at the beach. I was parked at the mouth of the Brazos River
down at Quintana Beach. I was also fishing.. I'd rig up my rod and reels,
putting them on auto pilot, and then would kick back and drink brewed
beverages while jibber jabbering on the radio. Mostly 40 and 80 meters.
If I saw a rod start to twitch, I'd put down the mike and adult beverage,
and reel in the fish.


I noticed this some years back when reading a paper, as I recall written
by the US Navy, which played down the importance of ground conductivity,
other when either at sea or in close proximity to the shore.

I've never really worried about it too awful much. I don't really rely
on it, one way or the other. Even with decent ground quality, I still
run a good radial set, or if elevated, enough radials to do the job,
as if the ground were poor. Of course, I can't control the ground
conductivity away from my QTH. So no use worrying about it.


There is a world atlas of conductivity which is on the web, I can't
recall the URL, but it is worth looking out. The various seas and oceans
do vary, I recall the Baltic being less conductive for example.
Likewise, some of the patterns in the various countries are rather
intriguing. Some areas you would expect to be conductive are not. I
assume due to local rock formations etc.

The only map I've seen is one that is in the ARRL handbooks.. It's the
one that shows this area as 30 mS. I think it only covered the US, or
maybe North America at the max.. Don't know about the rest of the planet.