On Mon, 05 Sep 2005 21:32:45 -0400, Walter Maxwell
wrote:

Well, Danny, ya had to go and do it din't ya? Now people who see my
face in post offices will know how to trace me through my mug shot you
just posted. I thought I'd gotten away with it. Somebody hire you to
post it? CSI? Law & Order? At least after I'm sent away to Attica
everybody, including you, will be able to find me.

Ya wanna know sumptin? I don't even have any remorse!

Walt

The devil made me do it! G

Danny

On Mon, 05 Sep 2005 22:22:37 -0400, Walter Maxwell
wrote:

On Mon, 05 Sep 2005 14:25:09 -0700, Dan Richardson wrote:

On Mon, 5 Sep 2005 15:31:18 -0500, (Richard
Harrison) wrote:
[snip]
As Walter flattered me, I`ll reciprocate. Get hold of the April 1973
issue of QST. Look on page 35. Walter is pictured there. He is a real
good looking fellow!
[snip]

If you don't have that QST handy you can see Walter he

http://users.adelphia.net/~k6mhe/BLE_de_W2DU.html

73,
Danny, K6MHE

Danny, I was just perusing the data in the post re the above url and
found a typo. In the ground radial data in the line showing 30
radials, the data for 0.4/wl indicating 158 mv/meter should read 185
mv/meter.


I think you mean the line for 60 radials? Anyway I changed that one to
the 185 figure.

Please double check it for me.

Thanks,
Danny, K6MHE

email: k6mheatarrldotnet
http://users.adelphia.net/~k6mhe/

On Mon, 05 Sep 2005 19:33:38 -0700, Dan Richardson wrote:

If you don't have that QST handy you can see Walter he

http://users.adelphia.net/~k6mhe/BLE_de_W2DU.html

73,
Danny, K6MHE

Danny, I was just perusing the data in the post re the above url and
found a typo. In the ground radial data in the line showing 30
radials, the data for 0.4/wl indicating 158 mv/meter should read 185
mv/meter.


I think you mean the line for 60 radials? Anyway I changed that one to
the 185 figure.

Please double check it for me.

Thanks,
Danny, K6MHE

email: k6mheatarrldotnet
http://users.adelphia.net/~k6mhe/

Ya done good, Danny, thanks.

Walt

"Walter Maxwell" wrote
Back on the subject of radials, unless the FCC has changed the
requirements since I was involved, the requirement is for 90
radials.
However, most of the AM BC stations I'm familiar with use 120, even
tho not required.

========================================
Walt,

Has it taken 70 years for the old wives of the FCC to return to Earth,
disregarding B.L & E who forgot to measure ground conductivity, not to
mention permittivity, and think again about economics?
----
Reg.

Has it taken 70 years for the old wives of the FCC to return to Earth,
disregarding B.L & E who forgot to measure ground conductivity, not to
mention permittivity, and think again about economics?

The only stations that the FCC is concerned about is commercial.
And the reason they stick with the standard number is for stability
and getting the max bang for buck, and an easily expected
performance level. Buying a load of wire will beat using more
transmitter power over the long run. If they use 120 radials,
they know they will be getting close to maximum performance.
If they don't, it's a crap shoot. 120 radials *will* outperform
16 of them. There is no question, unless they are over sea
water. I'm not saying hams have to run that many. In fact, I
think 60 will do for most, except the most hard core for good
results. Even less for the more casual user.
But I have no problems with the FCC wanting a certain level
of performance for commercial stations. I have no problems
seeing why they do it either. Wire is cheap compared to
todays level of monthly light bill. With some stations, the radials,
or lack of , in certain directions gives them a controlable
pattern with no surprises in f/s over a period of time
with changing ground conditions. The main thing is
stability of performance over periods of time. Or thats
my take anyway.
MK

All,

A fundamental basic question, which is the primary purpose of radials:

1. is it to create a ground, that is a as close as possible to zero ohm virtual
reference for the 'real' vertical half of the dipole?

2. Or are they to create a real resonant half of a dipole?

If it is the first then what does the 'efficiency' curve look like for a
shortened, loaded, vertical? That is if the vertical element is loaded to
resonate at 1/5 of a half wave length what does the ground resistance profile
look like for 120 radials at various lengths of 1/20 wave, 1/10 wave and 1/5 wave?

The question I am really driving at is if mesh is layed down at 100% coverage
about what fraction of a wave length needs to be covered to create a 2.5, 5, and
10 ohm equivalent ground for the vertical above?

In the paragraph above is the mesh simulating a ground or is it fact operating
as a ground.

Thanks,
Dan

wrote:
Has it taken 70 years for the old wives of the FCC to return to Earth,
disregarding B.L & E who forgot to measure ground conductivity, not to
mention permittivity, and think again about economics?

The only stations that the FCC is concerned about is commercial.
And the reason they stick with the standard number is for stability
and getting the max bang for buck, and an easily expected
performance level. Buying a load of wire will beat using more
transmitter power over the long run. If they use 120 radials,
they know they will be getting close to maximum performance.
If they don't, it's a crap shoot. 120 radials *will* outperform
16 of them. There is no question, unless they are over sea
water. I'm not saying hams have to run that many. In fact, I
think 60 will do for most, except the most hard core for good
results. Even less for the more casual user.
But I have no problems with the FCC wanting a certain level
of performance for commercial stations. I have no problems
seeing why they do it either. Wire is cheap compared to
todays level of monthly light bill. With some stations, the radials,
or lack of , in certain directions gives them a controlable
pattern with no surprises in f/s over a period of time
with changing ground conditions. The main thing is
stability of performance over periods of time. Or thats
my take anyway.
MK

MK,

How satisfying it is to read your message, written in plain, easy to
understand, well-punctuated English, without any undeciferable coded
abbreviations.

I agree with what you say although I am unfamiliar with exactly how
the FCC fits into the scheme of things.

Amateurs and commercial broadcasters have a common fundamental
requirement. There is a service area to be covered with a given field
strength. Depending on frequency, requirements then diverge. But the
design methods used to satisfy requirements are all confined (or
should be) to the principles of engineering economics. Inevitably, the
Dollar, Pound, Frank, Mark, Rouble and the Yen rule the roost.

Both commercial broadcasters and amateurs do a cost-befit analysis.
The broadcaster takes into account the revenue acruing from selling
the service. The amateur, whether he likes it or not, has to ask
himself what the satisfaction of using the station is worth.

Amateurs' bank accounts are not unlimited.

Field strength at the limits of the service area depends on the power
efficiency of the radiating system. If engineering economics dictate
use of a set of buried ground radials then the peformance of the
ground radials must be included. Considering the system as a whole,
it may be economical NOT to achieve the maximum possible radiating
efficiency. Indeed, the maximum is seldom the target.

If there is an economical choice in the matter, once the location of
the station is decided, everybody agrees that efficiency depends on
soil resistivity at the site. To estimate efficiency it is necessary,
at the very least, to make a guess at soil resistivity. Perhaps just
by looking at the type of weeds growing in it. Or it can be measured.

Depending on how far it enters into station economics, it is possible
to numerically estimate efficiency from the number and length of
radials AND FROM SOIL RESISTIVITY.

B.L & E and the FCC don't enter into it.
----
Reg.

========================================
MK wrote,
The only stations that the FCC is concerned about is commercial.
And the reason they stick with the standard number is for stability
and getting the max bang for buck, and an easily expected
performance level. Buying a load of wire will beat using more
transmitter power over the long run. If they use 120 radials,
they know they will be getting close to maximum performance.
If they don't, it's a crap shoot. 120 radials *will* outperform
16 of them. There is no question, unless they are over sea
water. I'm not saying hams have to run that many. In fact, I
think 60 will do for most, except the most hard core for good
results. Even less for the more casual user.
But I have no problems with the FCC wanting a certain level
of performance for commercial stations. I have no problems
seeing why they do it either. Wire is cheap compared to
todays level of monthly light bill. With some stations, the
radials,
or lack of , in certain directions gives them a controlable
pattern with no surprises in f/s over a period of time
with changing ground conditions. The main thing is
stability of performance over periods of time. Or thats
my take anyway.
MK

On Wed, 7 Sep 2005 14:07:39 +0000 (UTC), "Reg Edwards"
wrote:

MK,

How satisfying it is to read your message, written in plain, easy to
understand, well-punctuated English, without any undeciferable coded
abbreviations.

I agree with what you say although I am unfamiliar with exactly how
the FCC fits into the scheme of things.

Amateurs and commercial broadcasters have a common fundamental
requirement. There is a service area to be covered with a given field
strength. Depending on frequency, requirements then diverge. But the
design methods used to satisfy requirements are all confined (or
should be) to the principles of engineering economics. Inevitably, the
Dollar, Pound, Frank, Mark, Rouble and the Yen rule the roost.

Both commercial broadcasters and amateurs do a cost-befit analysis.
The broadcaster takes into account the revenue acruing from selling
the service. The amateur, whether he likes it or not, has to ask
himself what the satisfaction of using the station is worth.

Amateurs' bank accounts are not unlimited.

Field strength at the limits of the service area depends on the power
efficiency of the radiating system. If engineering economics dictate
use of a set of buried ground radials then the peformance of the
ground radials must be included. Considering the system as a whole,
it may be economical NOT to achieve the maximum possible radiating
efficiency. Indeed, the maximum is seldom the target.

If there is an economical choice in the matter, once the location of
the station is decided, everybody agrees that efficiency depends on
soil resistivity at the site. To estimate efficiency it is necessary,
at the very least, to make a guess at soil resistivity. Perhaps just
by looking at the type of weeds growing in it. Or it can be measured.

Depending on how far it enters into station economics, it is possible
to numerically estimate efficiency from the number and length of
radials AND FROM SOIL RESISTIVITY.

B.L & E and the FCC don't enter into it.
----
Reg.

Sorry to disagree, Reg, but it appears you're overlooking an important
point--the difference between the efficiency of the radiating system
itself, versus the efficiency of the ground area external to the
radiating system.

BL&E shows that when 90 - 120 (actually 113) radials of 0,4 w/l form
the ground system for a 1/4 wl radiator, the efficiency is 98.7%
efficient, REGARDLESS OF THE SOIL RESISTIVITY UNDER THE RADIALS. This
is shown by obtaining the field strength of 192 mv/meter at 1 mile for
1000 watts delivered to the antenna under the conditions described
above, compared to 194.5 mv/meter with a perfect ground having an
efficiency of 100%

It is only the soil resistivity of the ground external to the radial
system that determines the field stength external to the radial
system. Consequently, the soil resistivity (or conductivity, if you
like) is significant only in the areas external to the radial system.

Walt, W2DU

On Wed, 07 Sep 2005 11:41:33 -0400, Walter Maxwell
wrote:

Sorry to disagree, Reg, but it appears you're overlooking an important
point--the difference between the efficiency of the radiating system
itself, versus the efficiency of the ground area external to the
radiating system.

Walter, my friend, you're beating a dead horse. It would appear that
Reg's mind is made up and no amount factual proof is going to change
it.

Had BL&E been Englishmen I sure things would be different.G

73,
Danny, K6MHE

On Wed, 07 Sep 2005 09:39:28 -0700, Dan Richardson wrote:

On Wed, 07 Sep 2005 11:41:33 -0400, Walter Maxwell
wrote:

Sorry to disagree, Reg, but it appears you're overlooking an important
point--the difference between the efficiency of the radiating system
itself, versus the efficiency of the ground area external to the
radiating system.

Walter, my friend, you're beating a dead horse. It would appear that
Reg's mind is made up and no amount factual proof is going to change
it.

Had BL&E been Englishmen I sure things would be different.G

73,
Danny, K6MHE

Good point, Danny, how true.

Walt