Richard Clark wrote:

On Thu, 27 May 2010 17:36:41 -0700, Bob Smits wrote:

Is there a significant difference between using the galvanized steel
ground rods and copper to create an rf gound?

Hi Bob,

Two answers for that:
1. No difference whatever;
B. Neither make an RF ground.

Updates will follow this brief announcement.

73's
Richard Clark, KB7QHC

Looks like my follow up post didn't make it through.

Richard I intend these three ground rods to be the start of grounding my
station, not as a counterpoise for one of my antennas. These will be bonded
to my radios and the electrical service entrance ground.

Why do you say this does not make an RF ground?

Thanks, Bob

On Sat, 29 May 2010 17:04:16 -0700, Robert Smits
wrote:

Why do you say this does not make an RF ground?

Hi Bob,

If by "this" you mean the three rods, then they will NOT make an RF
ground.

Of necessity due to wavelength, your ground must be spread out (not
buried) to one quarter wavelength. For 160M, your radials (not ground
rods), should extend 40 meters from your radiator.

Classically, you would need 120 radials for an RF ground.

Classicism and practical reality diverge, so there are variations on
all of this EXCEPT ground rods do not make an RF ground.

73's
Richard Clark, KB7QHC

In article ,
Richard Clark wrote:

Of necessity due to wavelength, your ground must be spread out (not
buried) to one quarter wavelength.

Richard-

I have a steel well pipe that is approximately a quarter wave on 40
Meters. Even though it is buried, why wouldn't this work as the bottom
half of a vertical dipole?

I tried it with a mobile whip as the vertical element. It worked better
than I expected, but not really well.

Fred
K4DII

On Mon, 31 May 2010 00:33:00 -0400, Fred McKenzie
wrote:

I have a steel well pipe that is approximately a quarter wave on 40
Meters. Even though it is buried, why wouldn't this work as the bottom
half of a vertical dipole?

Hi Fred,

One perspective of the radial field is that it shields the radiator
from the loss of ground. However, that simplification disguises the
fact that the radials radiate too - and unproductively. When every
radial's radiation is taken into consideration, opposite radials (each
one that is 180 degrees from the other) cancel.

That aside, their benefit is they conduct better than dirt. What this
means is more power goes into copper/steel instead.

Now, if we consider your well pipe, it goes deeper into that lossy
dirt and the deeper it goes, the more dirt the return signal (to the
other, the vertical radiator) has to go through. More loss than use.

OK, another reason. For as poor/well as dirt may conduct, it too has
skin effect. This means at some distance into the dirt, conductivity
plummets because of skin effect. Deeper yet, and the skin effect loss
increases at a quick clip.

As skin effect is frequency dependent, at really low frequencies, your
well pipe has some advantage. This frequency range is suitable for
working lightning whose top end is 1MHz. At 7 MHz, there's no point.

I tried it with a mobile whip as the vertical element. It worked better
than I expected, but not really well.

Which shows you how crummy the whip is because what well pipe there
was that was above ground was doing the job of the whip.

Step back and look at the big picture using your analogy of a vertical
dipole with half of it buried. Now, convert that buried half into
multistrand. Bend each strand 90 degrees so that each strand just
rides an inch or two above ground with all of the newly bent strands
in a flat circular spray around the upper half. Walla! as the French
say.

73's
Richard Clark, KB7QHC

In article ,
Robert Smits wrote:

Richard Clark wrote:

On Thu, 27 May 2010 17:36:41 -0700, Bob Smits wrote:

Is there a significant difference between using the galvanized steel
ground rods and copper to create an rf gound?

Hi Bob,

Two answers for that:
1. No difference whatever;
B. Neither make an RF ground.

Updates will follow this brief announcement.

73's
Richard Clark, KB7QHC

Looks like my follow up post didn't make it through.

Richard I intend these three ground rods to be the start of grounding my
station, not as a counterpoise for one of my antennas. These will be bonded
to my radios and the electrical service entrance ground.

Why do you say this does not make an RF ground?

Thanks, Bob

A lot of folks, make the same mistake, in thinking that Electrical
Ground and RF Ground are the same thing. They, clearly, are NOT, the
same thing or even close to the same thing, unless you happen to be
living on a Salt Marsh. Ground Rods, of any kind, are only Electrical
Grounds. Rf Grounding is a Totally Different bag of cats. RF Grounds
need to be engineered, by someone who is familiar with Antenna Design
and Installation Procedures, for the particular Antenna and landscape,
where the antenna is to be installed.

On May 30, 5:00*pm, You wrote:
In article ,
*Robert Smits wrote:



Richard Clark wrote:

On Thu, 27 May 2010 17:36:41 -0700, Bob Smits wrote:

Is there a significant difference between using the galvanized steel
ground rods and copper to create an rf gound?

Hi Bob,

Two answers for that:
1. *No difference whatever;
B. *Neither make an RF ground.

Updates will follow this brief announcement.

73's
Richard Clark, KB7QHC

Looks like my follow up post didn't make it through.

Richard I intend these three ground rods to be the start of grounding my
station, not as a counterpoise for one of my antennas. These will be bonded
to my radios and the electrical service entrance ground.

Why do you say this does not make an RF ground?

Thanks, Bob

A lot of folks, make the same mistake, in thinking that Electrical
Ground and RF Ground are the same thing. They, clearly, are NOT, the
same thing or even close to the same thing, unless you happen to be
living on a Salt Marsh. Ground Rods, of any kind, are only Electrical
Grounds. Rf Grounding is a Totally Different bag of cats. RF Grounds
need to be engineered, by someone who is familiar with Antenna Design
and Installation Procedures, for the particular Antenna and landscape,
where the antenna is to be installed.

define "rf ground".

"K1TTT" wrote in message
...
On May 30, 5:00 pm, You wrote:
In article ,
Robert Smits wrote:



Richard Clark wrote:

On Thu, 27 May 2010 17:36:41 -0700, Bob Smits wrote:

Is there a significant difference between using the galvanized steel
ground rods and copper to create an rf gound?

Hi Bob,

Two answers for that:
1. No difference whatever;
B. Neither make an RF ground.

Updates will follow this brief announcement.

73's
Richard Clark, KB7QHC

Looks like my follow up post didn't make it through.

Richard I intend these three ground rods to be the start of grounding my
station, not as a counterpoise for one of my antennas. These will be
bonded
to my radios and the electrical service entrance ground.

Why do you say this does not make an RF ground?

Thanks, Bob

A lot of folks, make the same mistake, in thinking that Electrical
Ground and RF Ground are the same thing. They, clearly, are NOT, the
same thing or even close to the same thing, unless you happen to be
living on a Salt Marsh. Ground Rods, of any kind, are only Electrical
Grounds. Rf Grounding is a Totally Different bag of cats. RF Grounds
need to be engineered, by someone who is familiar with Antenna Design
and Installation Procedures, for the particular Antenna and landscape,
where the antenna is to be installed.

define "rf ground".

Something that provides a counterpoise for an unbalanced feedline
situation that doesn't result in RF energy being wasted to heat
earthworms, soil, etc. and radiates RF energy efficiently.

On Jun 20, 3:14*pm, "Pete Bertini" wrote:
"K1TTT" wrote in message

...
On May 30, 5:00 pm, You wrote:



In article ,
Robert Smits wrote:

Richard Clark wrote:

On Thu, 27 May 2010 17:36:41 -0700, Bob Smits wrote:

Is there a significant difference between using the galvanized steel
ground rods and copper to create an rf gound?

Hi Bob,

Two answers for that:
1. No difference whatever;
B. Neither make an RF ground.

Updates will follow this brief announcement.

73's
Richard Clark, KB7QHC

Looks like my follow up post didn't make it through.

Richard I intend these three ground rods to be the start of grounding my
station, not as a counterpoise for one of my antennas. These will be
bonded
to my radios and the electrical service entrance ground.

Why do you say this does not make an RF ground?

Thanks, Bob

A lot of folks, make the same mistake, in thinking that Electrical
Ground and RF Ground are the same thing. They, clearly, are NOT, the
same thing or even close to the same thing, unless you happen to be
living on a Salt Marsh. Ground Rods, of any kind, are only Electrical
Grounds. Rf Grounding is a Totally Different bag of cats. RF Grounds
need to be engineered, by someone who is familiar with Antenna Design
and Installation Procedures, for the particular Antenna and landscape,
where the antenna is to be installed.

define "rf ground".

Something that provides a counterpoise for an unbalanced feedline
situation that doesn't result in RF energy being wasted to heat
earthworms, soil, etc. and radiates RF energy efficiently.

the ground radiates? that's interesting.

so the raised radials on my 80m 4-square would be considered an rf
ground?

"K1TTT" wrote in message
...
On Jun 20, 3:14 pm, "Pete Bertini" wrote:
"K1TTT" wrote in message

...
On May 30, 5:00 pm, You wrote:



In article ,
Robert Smits wrote:

Richard Clark wrote:

On Thu, 27 May 2010 17:36:41 -0700, Bob Smits
wrote:

Is there a significant difference between using the galvanized steel
ground rods and copper to create an rf gound?

Hi Bob,

Two answers for that:
1. No difference whatever;
B. Neither make an RF ground.

Updates will follow this brief announcement.

73's
Richard Clark, KB7QHC

Looks like my follow up post didn't make it through.

Richard I intend these three ground rods to be the start of grounding
my
station, not as a counterpoise for one of my antennas. These will be
bonded
to my radios and the electrical service entrance ground.

Why do you say this does not make an RF ground?

Thanks, Bob

A lot of folks, make the same mistake, in thinking that Electrical
Ground and RF Ground are the same thing. They, clearly, are NOT, the
same thing or even close to the same thing, unless you happen to be
living on a Salt Marsh. Ground Rods, of any kind, are only Electrical
Grounds. Rf Grounding is a Totally Different bag of cats. RF Grounds
need to be engineered, by someone who is familiar with Antenna Design
and Installation Procedures, for the particular Antenna and landscape,
where the antenna is to be installed.

define "rf ground".

Something that provides a counterpoise for an unbalanced feedline
situation that doesn't result in RF energy being wasted to heat
earthworms, soil, etc. and radiates RF energy efficiently.

the ground radiates? that's interesting.

so the raised radials on my 80m 4-square would be considered an rf
ground?

I would consider them to be an effective RF ground at their 1/4
wave resonant points, just as would a tuned artificial RF ground
used for stations at elevated locations.

Pete

In article ,
"Pete Bertini" wrote:

define "rf ground".

Something that provides a counterpoise for an unbalanced feedline
situation that doesn't result in RF energy being wasted to heat
earthworms, soil, etc. and radiates RF energy efficiently.

the ground radiates? that's interesting.

so the raised radials on my 80m 4-square would be considered an rf
ground?

I would consider them to be an effective RF ground at their 1/4
wave resonant points, just as would a tuned artificial RF ground
used for stations at elevated locations.

Pete

Actually, a "GOOD" RF Ground will exhibit a very LOW Impedance across a
broad Frequency Spectrum, and NOT just at any single Frequency.... When
designing an RF Grounding System for a particular Site/Antenna System,
it is almost as important to know the Frequencies, and Bandwidths, to be
transmitted on, as it is to know the practical design of the Antenna
itself. Earth Conductivity has a much smaller effect than most folks
think.