Don't forget that in the ground there are "travelling" Eddy currents,
being generated by all kinds od "services". The worst are in the areas
where trolley services, electric trains and other high power services
use ground as the other conductor or just being there. They can get so
bad that they can "eat" gas lines, water lines and cause accelerated
corrosion and breakage. They would definitely affect any "ground"
measurements and interfere with measurements.
Yuri K3BU.us
MVmanor.com
On Tue, Nov 15, 2016 at 01:24 PM, Jon Zaimes wrote:
> As I recall mine are typically in the hundreds of ohms or low
thousands, never as high as
20k, even on a 950 ft wire.
I do see large variations of these across my 12 acres, even
significantly different readings on each wire in a staggered phased
pair.
We have two different soil types, which may be a factor.
My ground rods are typically 3-5 feet, and water table is usually a
few inches deep or less.
73/Jon AA1K
Sent from my iPhone
On Nov 15, 2016, at 9:20 AM, Herbert Schoenbohm wrote:
I have reflection transformers at the end of every two wire Beverages
which I try to test by measuring the wires on the feed end. I remove
the transformer from the two wire WD1-A and check the resistance
between the two wires which tells me that through the reflection
transformer I have continuity. It measures about 40 ohms wire to
wire, this is done when I notice any performance change of the
antenna. Now come the next test that baffles me completely. When I
measure from either wire to my ground rods alone, to see what the
return resistance is, I get reading in the vicinity of 20K across
the 900 foot run. I understand that if the reading was very low it
would defeat the whole Beverage principle. But is 20K Ohms
reasonable, very good, or marginal? I use three foot foot rods at
either end and when I pull one out yesterday before moving it the
bottom 1/4 was moist and muddy. That Southern end of several
reversible Beverages is located about 100 feet or less from a sal
t marsh or salt pond. I also have to such antennas made up of ladder
line a DX Engineering components. They all appear to be working well
even though large grass has reach and covered portion of some of them.
But my question is what is a reasonable or good return ground
resistance for a 600' or 900' Beverage. I haven't found any sources
of information expect the saying that the higher Resistance the
better. Is this correct?
Herb Schoenbohm, KV4FZ
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