Vertical Antenna Performance Question
 

The interesting question then: Is the improved performance of
vertical antennas over horizontal dipoles on 75 meters at DX distances
due to a combination of direct radiation plus radiation from the
ground in the area of strong ground wave strength out hundreds of
meters? Is the ground wave leakage providing additional low signal
strength in both transmit and receive?

Gary - N0GW

That's always interesting - and usually without a good explanation.
I don't know how many times I've switched from one anntenna to another just
to have the quote"inferior in theory" antenna get better results than the
"better" antenna.
Antennas are magic. There may be a metal building or some
near-but-out-of-sight tv antenna mast or tin roof or aluminum-foil-lined
insulation giving some directivity.

Vertical Antenna Performance Question
 

On Fri, 15 Feb 2008 20:33:04 -0500, "AI4QJ" wrote:

But I am a heretic for not having mindlessly bowed in adoration at the altar
of the EZNEC god in blind faith as you and others have done.

Hi Dan,

Heretic? More Arthur's heathen love-child. Heretics, afterall,
reject the scripture they've studied to present alternatives.
Heathens' marginal knowledge is a limited skill for making soup from
missionaries. Run out of missionaries and heathens starve; at least a
heretic can scrounge up a meal by holding out a hat on a street
corner.

Do you claim to have a hat?

73's
Richard Clark, KB7QHC

Vertical Antenna Performance Question
 

On Feb 15, 7:33 pm, "AI4QJ" wrote:


But I am a heretic for not having mindlessly bowed in adoration at the altar
of the EZNEC god in blind faith as you and others have done. However, those
fanatic evangelists who live by blind faith alone have wisely plonked me so
as not to let their blood pressures rise at the spectre of the EZNEC god
being angered.

73

I'm confused... Art, is that you?
MK

Vertical Antenna Performance Question
 

"AI4QJ" wrote in
:


2. EZNEC is not a propagation modeler as its users are well aware;

If it cannot predict take-off angle then what good is it? It doesn't
matter if we warm the clouds directly above?

You may have issues with Roy, but it is pretty unprofessional to deride his
program on that account.

It does predict the angle of maximum radiated power. "Take off
angle" is a great term for those who believe that the energy exits the
antenna as a blob, all in one place, and no energy elsewhere.

It isn't a propagation tool, it's a design tool, and as such
propagation is not at issue. Apples/Oranges.

But you're a smart fellow, so I guess you are pulling our collective legs
here.. 8^)

- 73 de Mike N3LI -

Vertical Antenna Performance Question
 

Vertical Antenna Performance Question
 

Richard Clark wrote in
:

Heretic? More Arthur's heathen love-child. Heretics, afterall,
reject the scripture they've studied to present alternatives.
Heathens' marginal knowledge is a limited skill for making soup from
missionaries. Run out of missionaries and heathens starve; at least a
heretic can scrounge up a meal by holding out a hat on a street
corner.

Do you claim to have a hat?

Not even a banjo, I'll bet.

- 73 de Mike N3LI -

Vertical Antenna Performance Question
 

Vertical Antenna Performance Question
 

Mike Coslo wrote:
"AI4QJ" wrote in
:

2. EZNEC is not a propagation modeler as its users are well aware;
If it cannot predict take-off angle then what good is it? It doesn't
matter if we warm the clouds directly above?

You may have issues with Roy, but it is pretty unprofessional to deride his
program on that account.

It does predict the angle of maximum radiated power. "Take off
angle" is a great term for those who believe that the energy exits the
antenna as a blob, all in one place, and no energy elsewhere.

It isn't a propagation tool, it's a design tool, and as such
propagation is not at issue. Apples/Oranges.

But you're a smart fellow, so I guess you are pulling our collective legs
here.. 8^)

- 73 de Mike N3LI -

Watch it, Mike, he may plonk you, a fate worse than running out of
beer.
73,
Tom Donaly, KA6RUH

Vertical Antenna Performance Question
 

AI4QJ wrote:

"Richard Clark" wrote in message
...
On Fri, 15 Feb 2008 12:37:55 -0800 (PST), wrote:

AI4QJwrote:
I suspect that the EZNEC program is not designed for taking into
account
such "rare" phenomena as "ground wave propagation". So much for EZNEC
analysis at 75m.
...
EZNEC information tells you nothing about ground wave
propagation.

Two things wrong with this:
1. EZNEC does provide information about the radiation characteristics
along ground at any distance on an infinite, flat plane and at any
elevation above it;

Really? Can it follow the curvature of the earth from say, Illinois to
Germany?

Is there some part of "infinite, flat plane" that you fail to understand?

2. EZNEC is not a propagation modeler as its users are well aware;

If it cannot predict take-off angle then what good is it? It doesn't matter
if we warm the clouds directly above?

EZNEC provides horizontal, vertical and 3D radiation patterns. Is there
some other dimension you are interested in?

3. EZNEC models the 100M work of Brown, Lewis, & Epstein quite
closely. There is nothing in the body of RF literature to suggest
that the nature of radiation shifts suddenly in 7/8ths of a megahertz.

Yes, there is no abrupt shift at 75m (most obviously). Quite simply, as you
approach larger wavelengths, skywave characterstics lessen and groundwave
characteristics increase.

Which are functions of propagation, not antenna modeling.

But I am a heretic for not having mindlessly bowed in adoration at the altar
of the EZNEC god in blind faith as you and others have done. However, those
fanatic evangelists who live by blind faith alone have wisely plonked me so
as not to let their blood pressures rise at the spectre of the EZNEC god
being angered.

No, you sound more like someone with a grudge mixing apples and oranges.


--
Jim Pennino

Remove .spam.sux to reply.

Vertical Antenna Performance Question
 

On Sat, 16 Feb 2008 13:04:45 -0500, "AI4QJ" wrote:

defend yourself when I begin highlighting the
things that EZNEC CAN'T do

Hi Dan,

"EZNEC can't whiten my teeth" sounds like so much of your naive
whining; why would ANYONE put any effort to "defending" against that
kind of boorish trolling?

Well, obviously I do. When technical content is so lacking in your
complaint, all that is left are the humorous gaffs like:
EZNEC does provide information about the radiation characteristics
along ground at any distance on an infinite, flat plane
and at any elevation above it;

Really? Can it follow the curvature of the earth
where the distance between "flat plane" and "curvature" are separated
by only eleven words - a netzheimer's record for cognitive fading.

After all, as you are one of my groupies, you were trolling for this
response weren't you? ;-)

73's
Richard Clark, KB7QHC