Following is a posting similar to what I made on QRZ.com in reply to a guy who
was asking what kind of antenna to use out west in the mountains surrounded by
tall pines. It summarizes my recent experiences with a vertical on 80 m here
in central New Jersey:

Often you will hear the advice "Use a vertical. You will get the low angle of
radiation which you need for DX." Be very careful. Although this statement
may be true, you could still be disappointed, especially if you are surrounded
by trees, and being in the mountains, might have poor soil, which is necessary
for good vertical performance. I speak from experience. I have been building
and improving my 80 meter vertical recently, with disappointing results. It
is a full size quarter wave wire vertical, hung from a rope that goes from my
72 ft tower to a tree. I have 18 radials, 60 feet long. Now that is a pretty
good vertical, with no loading coils, with not very much that can be done to
improve it except maybe double the number of radials. I am located in central
New Jersey on sandy soil. I have used this antenna for the past several
weeks, mostly checking it out on DX. In no case has the vertical beaten out
the inverted vee at 60 feet. In nearly every case the antennas are virtually
identical. Even on DX to VK6 during CQWW this vertical should be kicking
major butt, but it is not. Ok, so a few days ago I modelled both antennas
with 4NEC2, and I made sure to include the appropriate parameters in the model
for my soil conditions (poor). And I overlaid both antenna patterns on the
same chart. Voila! There it is, the inverted vee beats the vertical at all
angles above 10 degrees, and is equal below 10 degrees. The moral of the
story, be careful about making assumptions regarding antenna performance
without having an A-B switch! And maybe the other lesson to be learned is how
meaningful the antenna modeling programs are.
So my conclusion is that even though the vertical might have the low angle
pattern, the losses in the soil do not allow the advantages to be realized.
Phased arrays of similar antennas over lossy soil may show the nice pattern
and f/b but the absolute value of gain expected may not be realized.

73 Rick K2XT

"Rick" wrote in message
...
Following is a posting similar to what I made on QRZ.com in reply to a guy
who
was asking what kind of antenna to use out west in the mountains
surrounded by
tall pines. It summarizes my recent experiences with a vertical on 80 m
here
in central New Jersey:

Often you will hear the advice "Use a vertical. You will get the low
angle of
radiation which you need for DX." Be very careful. Although this
statement
may be true, you could still be disappointed, especially if you are
surrounded
by trees, and being in the mountains, might have poor soil, which is
necessary
for good vertical performance. I speak from experience. I have been
building
and improving my 80 meter vertical recently, with disappointing results.
It
is a full size quarter wave wire vertical, hung from a rope that goes
from my
72 ft tower to a tree. I have 18 radials, 60 feet long. Now that is a
pretty
good vertical, with no loading coils, with not very much that can be done
to
improve it except maybe double the number of radials. I am located in
central
New Jersey on sandy soil. I have used this antenna for the past several
weeks, mostly checking it out on DX. In no case has the vertical beaten
out
the inverted vee at 60 feet. In nearly every case the antennas are
virtually
identical. Even on DX to VK6 during CQWW this vertical should be kicking
major butt, but it is not. Ok, so a few days ago I modelled both antennas
with 4NEC2, and I made sure to include the appropriate parameters in the
model
for my soil conditions (poor). And I overlaid both antenna patterns on
the
same chart. Voila! There it is, the inverted vee beats the vertical at
all
angles above 10 degrees, and is equal below 10 degrees. The moral of the
story, be careful about making assumptions regarding antenna performance
without having an A-B switch! And maybe the other lesson to be learned is
how
meaningful the antenna modeling programs are.
So my conclusion is that even though the vertical might have the low angle
pattern, the losses in the soil do not allow the advantages to be
realized.
Phased arrays of similar antennas over lossy soil may show the nice
pattern
and f/b but the absolute value of gain expected may not be realized.

73 Rick K2XT

It would be interesting to see what 4NEC does if you raise the feedpoint,
and centers of the radials, about 10 feet.

Tam/WB2TT

On Tue, 06 Nov 2007 22:27:26 GMT, (Rick) wrote:

Voila! There it is, the inverted vee beats the vertical at all
angles above 10 degrees, and is equal below 10 degrees.

Hi Rick,

You are simply comparing two verticals. UNLESS that "inverted vee" is
absolutely flat on the horizontal (and why would you call it an
"inverted vee?").

73's
Richard Clark, KB7QHC

You are simply comparing two verticals.

I don't see why you say that. One is mounted on the ground with 16 radials,
the other is simply 2 pcs of wire up 60 feet, with 120 degree included angle
in my example, although I can change the angle just by typing over top of the
120 I can make it anything I want.
My point was, a lot of people think that if they put up a vertical, even
taking care to put a good radial field under it, and they get a low angle of
radiation, they have the ultimate single element DX antenna. In fact, when
you take losses into consideration a simple inverted vee beats it at all angle
over 10 degrees and equals it below 10 degrees. I think that is a pretty
significant statement.

Rick K2XT

Rick wrote:
In fact, when
you take losses into consideration a simple inverted vee beats it at all angle
over 10 degrees and equals it below 10 degrees.

The average gain of a 1/4WL vertical monopole
with ground-mounted radials is in the ballpark
of 0 dB in all directions.

The average gain of a horizontal 1/2WL dipole
is in the ballpark of 6 dB in two directions.

It is extremely difficult, if not impossible,
for a vertical monopole to achieve 6 dB gain
in any direction.

It is extremely difficult, if not impossible,
for a horizontal dipole to achieve 0 dB gain
in all directions.

Comparing omnidirectional antennas to directional
antennas is like comparing apples and oranges.
Decide which characteristics are desirable and
erect whatever antenna works best for you.

Hint#1: A five-element Yagi makes a lousy net
control antenna.

Hint#2: A monopole with 120 radials has a lousy
front-to-back ratio.
--
73, Cecil http://www.w5dxp.com

"Cecil Moore" wrote
The average gain of a 1/4WL vertical monopole
with ground-mounted radials is in the ballpark
of 0 dB in all directions.

It is extremely difficult, if not impossible,
for a vertical monopole to achieve 6 dB gain
in any direction.
____________

Zero or six decibels with respect to what reference, Cecil?

If that reference is an isotropic radiator, then note that a typical
1/4-wave monopole and buried radial ground system used by commercial,
non-directional AM broadcast stations has an h-plane gain of about 5 dBi.
This value has been confirmed by thousands of groundwave field strength
measurements of such systems going back 70+ years. Also note that the gain
of this monopole over a perfect, infinite ground plane would be only 5.15
dBi, so a broadcast radiator is quite good indeed.

And -- a gain of more than 6 dBi is produced by broadcast monopoles whose
height exceeds 1/4-wave sufficiently. For example, the h-plane gain of a
1/2-wave broadcast monopole system is about 6.6 dBi (6.8 dBi over a perfect
ground plane).

RF

Richard Fry wrote:
"Cecil Moore" wrote
The average gain of a 1/4WL vertical monopole
with ground-mounted radials is in the ballpark
of 0 dB in all directions.

It is extremely difficult, if not impossible,
for a vertical monopole to achieve 6 dB gain
in any direction.

Zero or six decibels with respect to what reference, Cecil?

Sorry, I had a senior moment - should have been dBi.

If that reference is an isotropic radiator, then note that a typical
1/4-wave monopole and buried radial ground system used by commercial,
non-directional AM broadcast stations has an h-plane gain of about 5
dBi. This value has been confirmed by thousands of groundwave field
strength measurements of such systems going back 70+ years. Also note
that the gain of this monopole over a perfect, infinite ground plane
would be only 5.15 dBi, so a broadcast radiator is quite good indeed.

I was speaking of the typical ham radio 1/4WL monopole.
EZNEC's VERT1.EZ is an example of such an antenna with
a maximum gain of about 0 dBi.

The point was that the average 1/4WL amateur monopole
doesn't equal the maximum gain of an average 1/2WL dipole,
much less the gain of a more directional antenna.
--
73, Cecil http://www.w5dxp.com

On Nov 6, 6:05 pm, (Rick) wrote:

My point was, a lot of people think that if they put up a vertical, even
taking care to put a good radial field under it, and they get a low angle of
radiation, they have the ultimate single element DX antenna. In fact, when
you take losses into consideration a simple inverted vee beats it at all angle
over 10 degrees and equals it below 10 degrees. I think that is a pretty
significant statement.

Rick K2XT

The only thing is 16 radials is not really what I'd call a good radial
field.
After what I saw here, I don't even consider 32 radials as a very
good
radial field..
But when I elevated the antenna I did the see good DX performance.
It greatly lowers the ground losses to the point just a few radials
will
do the job.
It smoked my dipole on long paths. And as Roy says, I use mainly the
receiver to check, and also I do use an A/B switch..
But I also got plenty of checks on my signal, and of course they
matched the margins I saw on receive. My dipole was not at 60 ft,
but at 36 ft. But to VK land the GP always beat the dipole by
4 S units. And I really doubt raising my dipole to 60 ft would have
been
enough to even the score.
In theory, the ground losses of my GP at 36 ft with four radials
should
have been appx equal to a ground mount with 60 radials.
This on top of the decent ground conditions.
But I also have the advantage of having a clear shot at the horizon
with no clutter in the way. I know the ground/space wave greatly
increased when I elevated the vertical. I could work ground wave on
40m
about 90-100 miles or so. Nearly half way from Houston to San Antonio.
I'd be lucky to do 20 on the dipole.
But another thing... And this may surprise you.. My 40m mobile antenna
is better than my 36 ft high dipole at night if the path is over
800-1000
miles.. Tested it many times to make sure it wasn't a fluke.
I don't know how it would fare on 80m to dx vs the dipole..
Never really tested it. I really don't work that much dx on 80m for
some
reason.. I'm usually working NVIS..
MK

On Wed, 07 Nov 2007 00:05:36 GMT, (Rick) wrote:



You are simply comparing two verticals.

I don't see why you say that.

Hi Rick,

Given you did not specify that the "inverted vee" was completely flat
in the horizontal plane, it must be vertical to the degree it is not
flat.

The dominant polarization of an end-fire "inverted vee" is vertical.

Shy of a complete specification, you are comparing two verticals and
they are both lousy.

73's
Richard Clark, KB7QHC

On Nov 6, 4:27 pm, (Rick) wrote:

So my conclusion is that even though the vertical might have the low angle
pattern, the losses in the soil do not allow the advantages to be realized.
Phased arrays of similar antennas over lossy soil may show the nice pattern
and f/b but the absolute value of gain expected may not be realized.

73 Rick K2XT

I saw pretty much the same thing. If you want truly top notch
performance
ground mounted, you have to lay out the wire. Well, unless you are at
the beach or something.. :/
I ran mostly 40m using full size verticals, and even with 32 full
length radials,
I saw mediocre results at best. And I'm on a high rated ground as far
as
conductivity.
When I elevated the antenna to 36 ft at the base is when I finally saw
decent
performance.
Of course, it's not going to be easy to run a full size elevated
ground plane
on 80m..
The only way you are going to see the performance you should is by
coughing up more wire.
But according to some I read, 60 will do the trick rather than having
to do
the full blown 120.. Not a whole lot of difference between the two in
theory.
Even elevated at 1/8 wave, a ground plane needs appx sixty radials to
equal
a ground plane at 1/2 wave , using four radials.
And about 120 may well be needed if you really want to equal the
losses of
the high ground plane.
Ground clutter can be another problem, although usually not huge.
But, it's
just another reason why I prefer an elevated vertical if at all
possible.
As far as the modeling, I have to adjust the programs to "very good"
ground
to have it equal what I see in the real world at this QTH.
If they are set to default "average" ground, the verticals get
shortchanged.
But on the other hand, maybe that just tells me the ground here is
better
than average, which actually it is... :/ I'm on the gulf coast, and
most of
the area rates a "30" on the conductivity maps.
Thats no sure thing though.. Even though the ground is decent here, I
never had better than mediocre results using a ground mounted vertical
with 32 full length radials. I had very good results with the 36 ft
high ground
plane though. Was like day and night..
MK