On 18/01/2015 20:55, Bruno wrote:
Hi all,

I've had a planning application for a tower turned down which is a real
pain. My options are now very limited. I'm in a bungalow with a roof apex
height of 18 feet and I'm not allowed to put up anything much above this
roof line it transpires, so inverted vees that need to be mounted high up
at the feed point like G5RVs are not possible for me. My garden
boundaries limit the length of any wire antenna I might wish to put up to
about 120 feet overall. On the plus side, though, the QTH is several
hundred feet ASL close to the top of the hill and am not overshadowed by
any trees or buildings to speak of.
What's my best choice for an HF antenna under these circs? (I mostly do
CW on 20m & 40m, but would like a bit more band choice ideally if poss).
Many thanks.

Many thanks.


Your QTH is virtually identical to mine - max height of 18 foot, longest
clear run about 85 foot.

I use a doublet - just two 57 foot wires forming the radiator/feeder.
The ATU is 16 turns on a two inch former, tuned by a 250pF variable and
link coupled (about 7 turns) to the rig via a 1000pF variable. This
tunes/matches 80, 60, 40 and 20m. The two capacitors are actually
double 500pF caps - one with sections in series, the other with sections
in parallel.

If local interference is an issue it is important to keep the radiating
section as straight and as horizontal as possible.

PA

On Monday, January 19, 2015 at 12:31:04 AM UTC-6,
For 40m NVIS within 500 miles or so, the low dipole will likely smoke
most verticals.

Of course it will as all the energy will go straight up while the
vertical main lobe is at about 30 degrees.

The important factor is the height in wavelengths, not feet. As the
height drops below a half wavelength the main lobe goes vertical
on a dipole (or any horizontal antenna) rapidly.

Sure, but there is still enough at the low angles to make some DX
contacts. And he'll have a decent signal to the stations not so far
away on 40m.




I guess he'll have to decide what he wants to lean to. Whatever he decides
is unlikely to excel at both, and will be a compromise.

If local communications is your goal, then an NVIS antenns is what you
want. However as the frequency increases above about 8 MHz the
probablity for success decreases and drops to near zero at 30 MHz. For
20 meters it is a crap shoot with less than good sunspot activity.

The performance at low angles won't be quite as grim as you might expect.
IE: I had no trouble working 15m DX with a -10 ft high dipole. 20 ft up is
nearly a 1/2 on 15m. And a 20m dipole at 20 ft will be quite decent for
average use being over a 1/4 wave up. Will be good stateside, and usable
for DX. I like converted CB ground planes for 10m. Good space wave for
local, and good for DX. Not much close in sky wave stuff to work on that
band.


I don't really see how a dipole requiring three supports, two at best,
can be considered simpler than a vertical with one support.

A vertical generally needs radials unless it's a "1/2 wave" type
design. And even good verticals can be quite lackluster for close
in work compared to a low dipole on 40m. Good at night to DX though.
But like I say, he's gotta decide what he wants to concentrate on,
and go from there.

If he has trees to tie dipole legs to, he really only needs one
support for the apex. And one can also string them between trees
to where no man made supports are needed at all.
But I don't know what trees he has available.

I usually have one mast for the apex, and tie off to trees or whatever.
At the dirt patch, I use a oak tree as the apex support, and tie
off to other trees. I shoot a weighted line up into the apex tree,
and run it over a tall branch. Then I pull the dipole and coax back
up into the tree with the wire I shot over the tall branch.
When I go home, I let the wire loose, and back down it all falls.
I used to leave it there all the time, but the critters were eating
my coax into shreds, so I had to quit that. :/

And the tuner/ladder line fed dipoles is another option if one wants
all bands with one antenna.

On 18/01/15 20:55, Bruno wrote:

I've had a planning application for a tower turned down which is a real
pain. My options are now very limited. I'm in a bungalow with a roof apex
height of 18 feet and I'm not allowed to put up anything much above this
roof line it transpires, so inverted vees that need to be mounted high up
at the feed point like G5RVs are not possible for me. My garden
boundaries limit the length of any wire antenna I might wish to put up to
about 120 feet overall. On the plus side, though, the QTH is several
hundred feet ASL close to the top of the hill and am not overshadowed by
any trees or buildings to speak of.

What's my best choice for an HF antenna under these circs?

You could have two...a horizontal, as suggested by others, and then
there's this....

Consider is using the slope of the hill to your advantage.

How close to it are you? Over what arc of the compass does the slope cover?

My thinking is that you should consider ground-mounting a vertical as
close to the slope as possible. The down-slope will pull down the
vertical radiation lobe to perhaps all but the horizontal, giving you
effective gain over a vertical operating over level ground together with
the prospect of long hop-length DX from the low angle. The difference in
gain can be useful to significant., and the reduced number of hops can
reduce path losses. Get a great-circle map and see what sector of the
world is covered by the arc of the slope; you'll get the best reports
from within this arc.

The vertical need not be high at all. For the lower bands you could try
the following set-up; you could make it in an hour or so. An auto-tuner
would make this a breeze, but you can put together the following from
your junk box.

Wind a coil having an inductance of 0.25 x lambda for the band of
interest. For 40m this would be 0.25 x 40 = 10 microH. I make my coils
from flex stripped from scrap mains cable. You'll also need a variable
capacitor of about 1pF per lambda, but this isn't critical. Connect this
across the coil. Wind on a 4-turn link at the 'bottom' end of the coil
connected to 50 ohm coax and connect to your rig. To the 'top' end of
the coil, connect your vertical. Mine is 18' of wire taped to a roach
pole, for the lower bands. To the bottom end connect four radials, each
as long as the vertical is high. Connect to a screwdriver or very short
rod earth via an RF choke or 1k resistor. Do not bury the radials or
connect a massive earth, this one is to bleed static, nothing more. The
radials will couple the RF to ground.

It's my experience that when the length of the vertical becomes a
significant fraction of the wavelength (say 1/10th), the system begins
not to work so well - the solution is to tap the aerial connection down
the coil, but this adds complexity. Keep the vertical section short and
enjoy the simplicity. This is a try-out of the possibilities of your
QTH, after all.

I find that this set-up is very non-critical, and with a 200pF variable
and the right inductance it will tune over two bands, say 160/80, or
80/60/40. Above these bands the link's turns will need to be reduced and
the system self-capacitance can be a nuisance, so perhaps an auto-tuner
would be better. Your output power will be limited by the capacitor's
capability voltage-wise. The only drawback is retuning for each band, as
the tuner is located at the base of the antenna. I use mine in the
portable mode, so operating near the base of the antenna isn't a problem.

Using a similar set-up on a short (200') slope facing East, I can work
all of Russia, the Mediterranean, and Asia from the UK with good reports
and running less than 10W, on 17 and above (for which I use an
auto-tuner). I don't work 20m, never liked the band much, and below
that, the slope isn't really long enough to pull the vertical lobe down.
Hopefully, yours will be.

--
Spike

"Hard cases, it has frequently been observed, are apt to introduce bad
law". Judge Rolfe

On 20/01/15 03:54, wrote:
If he has trees to tie dipole legs to, he really only needs one
support for the apex. And one can also string them between trees
to where no man made supports are needed at all.
But I don't know what trees he has available.
=======================
When wire antennas are connected to trees ,with trees moving in (strong)
wind , I would recommend a pulley connected to the tree(s) and the
antenna end(s) connected to rope running over the pulley and weighted by
a brick/stone.

This keeps antenna under constant tension even when tree or its branches
are moving ,causing the brick/stone bobbing up & down.

Frank GM0CSZ / KN6WH in IO87AT

wrote:

snip

A vertical generally needs radials unless it's a "1/2 wave" type
design. And even good verticals can be quite lackluster for close
in work compared to a low dipole on 40m. Good at night to DX though.
But like I say, he's gotta decide what he wants to concentrate on,
and go from there.

You are all over the place here and mixing apples and oranges.

A vertical has a low elevation angle.

Any antenna that has a low elevation angle is "better" for distant
communications than an antenna with a very high elevation angles.

A horizontal antenna less than a half wavelength in height has a vey
high elevation angle. At .3 lambda it is 48 degrees, at .25 lambda
it is 62 degrees, and at .2 lambda it is 90 degrees, i.e. straight up.

This is called an NVIS antenna which is "better" for local communications
out to about 500 miles or so on the lower bands. NVIS communcations is
nearly nil much above 8 MHz at other than sunspot peaks. We are currently
past the peak of the current sunspot cycle and heading for a minimum.

A vertical antenna does not "need" radials, but it's performance is
improved by radials.

A vertical antenna over average ground has a main lobe at about 30 degees
and a gain of about 1 dBi.

A vertical antenna over perfect ground has a main lobe at 0 degrees and
a gain of about 5 dBi.

In a typical urban setting where there is landscaping and irrigation,
the ground is most likely average to very good unless you are in the
middle of a desert, which means even without radials the vertical's
gain is going to be a few dBi. Adding a few radials will improve the
gain and lower the main lobe but are not absolutely necessary.

Most verticals will get put in the middle of a lawn and it is trivial
to take a lawn edger or weed wacker and cut a groove in the grass down
to the dirt and staple down some radials. In such a setting you do
NOT need the 120 radials of a commercial broadcast station with it's
antenna in a barren field.


If he has trees to tie dipole legs to, he really only needs one
support for the apex.

The bottom line is a horizontal antenna needs three supports.

snip

And the tuner/ladder line fed dipoles is another option if one wants
all bands with one antenna.

As is a vertical piece of aluminum tubing of whatever height you can
put up with an ATU at the base of it.


--
Jim Pennino

On 1/20/2015 12:30 PM, wrote:
wrote:

snip

A vertical generally needs radials unless it's a "1/2 wave" type
design. And even good verticals can be quite lackluster for close
in work compared to a low dipole on 40m. Good at night to DX though.
But like I say, he's gotta decide what he wants to concentrate on,
and go from there.

You are all over the place here and mixing apples and oranges.

In what way? Seems perfectly reasonable and informative to me.

A vertical has a low elevation angle.

You will have to describe the conditions for that to be a truthful
general statement. Do you mean ground mounted with buried radials,
radials lying on the surface, elevated verticals with radials, or
half-wave verticals with no radials?

Any antenna that has a low elevation angle is "better" for distant
communications than an antenna with a very high elevation angles.

I think that is agreeable by all.

A horizontal antenna less than a half wavelength in height has a vey
high elevation angle. At .3 lambda it is 48 degrees, at .25 lambda
it is 62 degrees, and at .2 lambda it is 90 degrees, i.e. straight up.

According to the simulation programs, that is probably true. But, that
is the angle of *maximum* radiation. How much signal is available at the
3dB, 6dB, 10dB, 20dB angles? If you are running 100 watts, you still
have 1 watt available at the 20dB angle.

This is called an NVIS antenna which is "better" for local communications
out to about 500 miles or so on the lower bands. NVIS communcations is
nearly nil much above 8 MHz at other than sunspot peaks. We are currently
past the peak of the current sunspot cycle and heading for a minimum.

Can you supply support to some other source for this conclusion?

A vertical antenna does not "need" radials, but it's performance is
improved by radials.

It depends on the design.

A vertical antenna over average ground has a main lobe at about 30 degees
and a gain of about 1 dBi.

Please supply configuration of the antenna as mentioned above.

A vertical antenna over perfect ground has a main lobe at 0 degrees and
a gain of about 5 dBi.

Again, please supply configuration of the antenna as mentioned above.

In a typical urban setting where there is landscaping and irrigation,
the ground is most likely average to very good unless you are in the
middle of a desert, which means even without radials the vertical's
gain is going to be a few dBi. Adding a few radials will improve the
gain and lower the main lobe but are not absolutely necessary.

I think this is unsubstantiated unless you can supply supporting
documentation.

Most verticals will get put in the middle of a lawn and it is trivial
to take a lawn edger or weed wacker and cut a groove in the grass down
to the dirt and staple down some radials. In such a setting you do
NOT need the 120 radials of a commercial broadcast station with it's
antenna in a barren field.

Most verticals will be installed depending on the installers resources,
abilities, and present knowledge of antennas.


If he has trees to tie dipole legs to, he really only needs one
support for the apex.

The bottom line is a horizontal antenna needs three supports.

Actually, a 40 meter dipole can use two supports (trees) and can work
the US easily with a 50W transmitter.

snip

John S wrote:
On 1/20/2015 12:30 PM, wrote:
wrote:

snip

A vertical generally needs radials unless it's a "1/2 wave" type
design. And even good verticals can be quite lackluster for close
in work compared to a low dipole on 40m. Good at night to DX though.
But like I say, he's gotta decide what he wants to concentrate on,
and go from there.

You are all over the place here and mixing apples and oranges.

In what way? Seems perfectly reasonable and informative to me.

A vertical has a low elevation angle.

You will have to describe the conditions for that to be a truthful
general statement. Do you mean ground mounted with buried radials,
radials lying on the surface, elevated verticals with radials, or
half-wave verticals with no radials?

Most people mean ground mounted when they use the term vertical and
ground plane for an elevated vertical.

I meant ground mounted and the radials or lack of them is essentially
irrelevant.

Any antenna that has a low elevation angle is "better" for distant
communications than an antenna with a very high elevation angles.

I think that is agreeable by all.

I would certainly hope so.

A horizontal antenna less than a half wavelength in height has a vey
high elevation angle. At .3 lambda it is 48 degrees, at .25 lambda
it is 62 degrees, and at .2 lambda it is 90 degrees, i.e. straight up.

According to the simulation programs, that is probably true.

As well as basic physics.

But, that
is the angle of *maximum* radiation. How much signal is available at the
3dB, 6dB, 10dB, 20dB angles? If you are running 100 watts, you still
have 1 watt available at the 20dB angle.

I would be glad to run the numbers for you.

Do you want it as a comparsion between a vertical with no radials,
a vertical with radials, both over average ground, and a vertical
with perfect ground?

This is called an NVIS antenna which is "better" for local communications
out to about 500 miles or so on the lower bands. NVIS communcations is
nearly nil much above 8 MHz at other than sunspot peaks. We are currently
past the peak of the current sunspot cycle and heading for a minimum.

Can you supply support to some other source for this conclusion?

I assume you mean for NVIS communications and not the sunspot cycle:

http://en.wikipedia.org/wiki/Near_ve...idence_skywave
http://www.w0ipl.net/ECom/NVIS/nvis.htm
http://www.w5jck.com/nvis/W5JCK-NVIS...esentation.pdf
https://www.txarmymars.org/.../NVIS-...and-Design.pdf
http://www.qsl.net/wb5ude/nvis/
http://home.centurytel.net/w9wis/NVIS.html

Want more?


A vertical antenna does not "need" radials, but it's performance is
improved by radials.

It depends on the design.

The design is a metal tube about .25 lambda long mounted close to the
ground and fed at the bottom end.

A vertical antenna over average ground has a main lobe at about 30 degees
and a gain of about 1 dBi.

Please supply configuration of the antenna as mentioned above.

A metal tube about .25 lambda long mounted close to the ground and fed at
the bottom end.


A vertical antenna over perfect ground has a main lobe at 0 degrees and
a gain of about 5 dBi.

Again, please supply configuration of the antenna as mentioned above.

A metal tube about .25 lambda long mounted close to the ground and fed at
the bottom end.

In a typical urban setting where there is landscaping and irrigation,
the ground is most likely average to very good unless you are in the
middle of a desert, which means even without radials the vertical's
gain is going to be a few dBi. Adding a few radials will improve the
gain and lower the main lobe but are not absolutely necessary.

I think this is unsubstantiated unless you can supply supporting
documentation.

Trivially demonstrated by any antenna simulation program.

Or are you looking for numbers on ground conductivity?

Google ground conductivity

Want to measure it yourself, read this:

http://www.technik.dhbw-ravensburg.d...ductivity.html

Most verticals will get put in the middle of a lawn and it is trivial
to take a lawn edger or weed wacker and cut a groove in the grass down
to the dirt and staple down some radials. In such a setting you do
NOT need the 120 radials of a commercial broadcast station with it's
antenna in a barren field.

Most verticals will be installed depending on the installers resources,
abilities, and present knowledge of antennas.

The same can be said for making cookies; so what?

One of the purposes of this group is the dissemination of antenna
knowledge. I make no assumptions about the readers other than the
ability to read.


If he has trees to tie dipole legs to, he really only needs one
support for the apex.

The bottom line is a horizontal antenna needs three supports.

Actually, a 40 meter dipole can use two supports (trees) and can work
the US easily with a 50W transmitter.

Sure, if you use very heavy wire for the dipole and very light feed line.

BTW, most amateur rigs these days put out 100 Watts.



--
Jim Pennino

On Tuesday, January 20, 2015 at 12:31:04 PM UTC-6, wrote:
wrote:

snip

A vertical generally needs radials unless it's a "1/2 wave" type
design. And even good verticals can be quite lackluster for close
in work compared to a low dipole on 40m. Good at night to DX though.
But like I say, he's gotta decide what he wants to concentrate on,
and go from there.

You are all over the place here and mixing apples and oranges.

Yes, because you are dealing with apples and oranges in the real
world, and until he comes back and describes what mode of operation
he prefers most of the time, I include both options.


A vertical has a low elevation angle.

And not much at the higher angles. Which will make it fairly
poor compared to a low dipole when used for general 40m NVIS
use, say in the daytime.


Any antenna that has a low elevation angle is "better" for distant
communications than an antenna with a very high elevation angles.

Sure, but until he comes back and describes his usual mode of
operation, I'm not sure if that is what he wants at all times.


A horizontal antenna less than a half wavelength in height has a vey
high elevation angle. At .3 lambda it is 48 degrees, at .25 lambda
it is 62 degrees, and at .2 lambda it is 90 degrees, i.e. straight up.

I've modeled and used antennas for many years..
I know the usual patterns of the various options.


This is called an NVIS antenna which is "better" for local communications
out to about 500 miles or so on the lower bands. NVIS communcations is
nearly nil much above 8 MHz at other than sunspot peaks. We are currently
past the peak of the current sunspot cycle and heading for a minimum.

The angles used for 20m stateside can be fairly high. I know from
experience that a 20m dipole at 20 ft will work quite well for
average distances. It will be quite good within 1500 miles, and
still quite usable at DX distances. It will generally be a good
performing antenna for overall use.

And if the band condx are heading down as you say, he would more
likely be on 40 and 20, than the higher bands.
Will he work 40m in the daytime? If so, he will want to be on the
low dipole, rather than the vertical. Would be like comparing
fresh cut oranges to rotten apples. :/


A vertical antenna does not "need" radials, but it's performance is
improved by radials.

Sure. But if he's over med to poor ground, the losses can be
substantial. I'm over quite good ground being on the Gulf Coast,
and I had a full size 32 ft tall 40m vertical ground mounted with
32 radials. It was OK, but no real DX buster. At all..

I then raised the antenna to 36 ft at the base, and used 4 sloping
radials as a ground plane. That antenna absolutely smoked the
ground mount antenna to DX. So the ground radials obviously
were a factor, and I'm over pretty good ground.


A vertical antenna over average ground has a main lobe at about 30 degees
and a gain of about 1 dBi.

And?


A vertical antenna over perfect ground has a main lobe at 0 degrees and
a gain of about 5 dBi.

I don't know anyone who lives on perfect ground. :|


In a typical urban setting where there is landscaping and irrigation,
the ground is most likely average to very good unless you are in the
middle of a desert, which means even without radials the vertical's
gain is going to be a few dBi. Adding a few radials will improve the
gain and lower the main lobe but are not absolutely necessary.

That is true for the area I live on, and obviously the number of radials
made quite a difference in my case. Raising the antenna let me use
less radials to equal a certain number on the ground. I was using
32 on the ground for only so-so DX performance.
The four I used at 36 ft were equal to about 60 or so on the ground
at that height in wavelength on 40m.


Most verticals will get put in the middle of a lawn and it is trivial
to take a lawn edger or weed wacker and cut a groove in the grass down
to the dirt and staple down some radials. In such a setting you do
NOT need the 120 radials of a commercial broadcast station with it's
antenna in a barren field.

I'd want a decent number to really brown the food. And you have to
consider the price of wire these days. Copper wire can add up to $$$$.



If he has trees to tie dipole legs to, he really only needs one
support for the apex.

The bottom line is a horizontal antenna needs three supports.

Not if you use two supports for the whole antenna, and let the
feed line drop from the center down to the ground and then to the shack.
He doesn't actually have to let it drop to the ground, but in the case
of coax fed, I prefer that in case of a lightning strike. And snubbing
the shield to a ground stake at that point, even better.
I like metal masts as an apex support, as it will usually take the
strike and route it to ground, instead of the antenna, as long as the
mast extends slightly over the feed point of the antenna.


snip

And the tuner/ladder line fed dipoles is another option if one wants
all bands with one antenna.

As is a vertical piece of aluminum tubing of whatever height you can
put up with an ATU at the base of it.

Sure, I never said it wasn't.
Almost a gazillion options in the wide wide world of antennas.
But until he comes back and describes his usual mode of operation,
I feel it's best to include all options, and not just limit it to
verticals.

On Tue, 20 Jan 2015 16:09:25 +0000, Spike wrote:

How close to it are you? Over what arc of the compass does the slope
cover?

Good point. I'd forgot to specify that. I'm about fairly close to the
summit and the ground drops away mainly to the SSE with the coast about a
mile away. From here I can see couple of miles out to sea. Since I'm in
the centre of the British Isles, I'm in a great position for getting good
signals to and from South Africa - but not really anywhere else! :-(

wrote:
On Tuesday, January 20, 2015 at 12:31:04 PM UTC-6, wrote:
wrote:

snip

A vertical generally needs radials unless it's a "1/2 wave" type
design. And even good verticals can be quite lackluster for close
in work compared to a low dipole on 40m. Good at night to DX though.
But like I say, he's gotta decide what he wants to concentrate on,
and go from there.

You are all over the place here and mixing apples and oranges.

Yes, because you are dealing with apples and oranges in the real
world, and until he comes back and describes what mode of operation
he prefers most of the time, I include both options.

What he prefers is irrelevant to a general discussion about how antennas
work.



A vertical has a low elevation angle.

And not much at the higher angles. Which will make it fairly
poor compared to a low dipole when used for general 40m NVIS
use, say in the daytime.

Obviously.


Any antenna that has a low elevation angle is "better" for distant
communications than an antenna with a very high elevation angles.

Sure, but until he comes back and describes his usual mode of
operation, I'm not sure if that is what he wants at all times.

What he prefers is irrelevant to a general discussion about how antennas
work.

A horizontal antenna less than a half wavelength in height has a vey
high elevation angle. At .3 lambda it is 48 degrees, at .25 lambda
it is 62 degrees, and at .2 lambda it is 90 degrees, i.e. straight up.

I've modeled and used antennas for many years..
I know the usual patterns of the various options.


This is called an NVIS antenna which is "better" for local communications
out to about 500 miles or so on the lower bands. NVIS communcations is
nearly nil much above 8 MHz at other than sunspot peaks. We are currently
past the peak of the current sunspot cycle and heading for a minimum.

The angles used for 20m stateside can be fairly high. I know from
experience that a 20m dipole at 20 ft will work quite well for

How high in wavelengths is 20 feet at 20M and how does that relate to
what I have already said about antenna height?

average distances. It will be quite good within 1500 miles, and
still quite usable at DX distances. It will generally be a good
performing antenna for overall use.

And if the band condx are heading down as you say, he would more
likely be on 40 and 20, than the higher bands.

I said we are heading for a sunspot minimum, which means that NVIS
communications is gettting more and more unlikely above 8 MHz.

Will he work 40m in the daytime? If so, he will want to be on the
low dipole, rather than the vertical. Would be like comparing
fresh cut oranges to rotten apples. :/

What he prefers is irrelevant to a general discussion about how antennas
work.

A vertical antenna does not "need" radials, but it's performance is
improved by radials.

Sure. But if he's over med to poor ground, the losses can be
substantial. I'm over quite good ground being on the Gulf Coast,
and I had a full size 32 ft tall 40m vertical ground mounted with
32 radials. It was OK, but no real DX buster. At all..

If, if, if.

The reality is most people live on average to good ground if for no
other reason than they landscape it.

I then raised the antenna to 36 ft at the base, and used 4 sloping
radials as a ground plane. That antenna absolutely smoked the
ground mount antenna to DX. So the ground radials obviously
were a factor, and I'm over pretty good ground.

The biggest factor is that you elevated it. Here are the numbers for
a ground plane with 45 degree radials for various heights:

Height is in wavelengths above ground for the bottom of the radials
and @ elev is the elevation angle of the main lobe.


Height gain @ elev

0.01 0.78 21
0.10 1.32 18
0.15 1.50 17
0.20 1.59 15
0.25 1.63 15
0.30 1.63 14
0.35 1.62 13
0.40 1.63 13
0.45 2.02 43
0.50 2.37 40
0.55 2.64 38
0.60 2.86 36
0.65 3.03 34
0.70 3.15 32
0.75 3.21 30
0.80 3.22 29
0.85 3.18 27
0.90 3.16 9
0.95 3.29 9
1.00 3.42 9
1.05 3.54 9
1.10 3.67 9
1.15 3.81 8
1.20 3.95 8
1.25 4.07 8


A vertical antenna over average ground has a main lobe at about 30 degees
and a gain of about 1 dBi.

And?

And it is a fact.

A vertical antenna over perfect ground has a main lobe at 0 degrees and
a gain of about 5 dBi.

I don't know anyone who lives on perfect ground. :|

Neither do I but it is the reference for being as good as one can get,
i.e. the best you could possible do with a huge number of radials.

In a typical urban setting where there is landscaping and irrigation,
the ground is most likely average to very good unless you are in the
middle of a desert, which means even without radials the vertical's
gain is going to be a few dBi. Adding a few radials will improve the
gain and lower the main lobe but are not absolutely necessary.

That is true for the area I live on, and obviously the number of radials
made quite a difference in my case. Raising the antenna let me use
less radials to equal a certain number on the ground. I was using
32 on the ground for only so-so DX performance.
The four I used at 36 ft were equal to about 60 or so on the ground
at that height in wavelength on 40m.

Which is, for a lot of people, a well known phenomenon.

You get more gain by elevating the antenna.

You also have the effect that 4 elevated radials, even if only elevated
a very small distance, are equivelant to a great number of buried
radials, i.e. more closely approximates the perfect ground that doesn't
exist.

Most verticals will get put in the middle of a lawn and it is trivial
to take a lawn edger or weed wacker and cut a groove in the grass down
to the dirt and staple down some radials. In such a setting you do
NOT need the 120 radials of a commercial broadcast station with it's
antenna in a barren field.

I'd want a decent number to really brown the food. And you have to
consider the price of wire these days. Copper wire can add up to $$$$.

14 AWF THHN wire brand new from Lowes costs about $0.09/foot and will
work just fine for radials.

If you are really cheap, you can find surplus wire at swap meets for
much less than that.


If he has trees to tie dipole legs to, he really only needs one
support for the apex.

The bottom line is a horizontal antenna needs three supports.

Not if you use two supports for the whole antenna, and let the
feed line drop from the center down to the ground and then to the shack.
He doesn't actually have to let it drop to the ground, but in the case
of coax fed, I prefer that in case of a lightning strike. And snubbing
the shield to a ground stake at that point, even better.
I like metal masts as an apex support, as it will usually take the
strike and route it to ground, instead of the antenna, as long as the
mast extends slightly over the feed point of the antenna.

Sure, like I said and which you snipped, if you use heavy wire for the
dipole and a light feed line. You are still at at least two supports.

snip

And the tuner/ladder line fed dipoles is another option if one wants
all bands with one antenna.

As is a vertical piece of aluminum tubing of whatever height you can
put up with an ATU at the base of it.

Sure, I never said it wasn't.
Almost a gazillion options in the wide wide world of antennas.
But until he comes back and describes his usual mode of operation,
I feel it's best to include all options, and not just limit it to
verticals.

What he prefers is irrelevant to a general discussion about how antennas
work.

And I did NOT limit the discussion to verticals, I compared low mounted
horizontal antennas to vertical antennas.


--
Jim Pennino