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So who actually has the space and resources to set up an ideal
horizontal dipole on HF with the full length and height as specified
in all the formulas? Wouldn't it be cheaper and easier to set up a
vertical if you could install something that high off the ground?

The only thing I've seen personally that looks like it meets the ideal
is a small station tucked into the northeast cloverleaf of an exit off
Interstate 93 near Boston, MA, and the station appeared to be a marker
for Logan. Anyone have any personal, real-life experience with a
full-size, full-height HF dipole? Is it worth the cost?

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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On Fri, 14 May 2004 10:04:38 -0700, Jack Twilley
wrote:
Anyone have any personal, real-life experience with a
full-size, full-height HF dipole? Is it worth the cost?

Hi Jack,

There is no such thing. Full size and Full height for a band that has
a frequencies spanning 15:1 is a contradiction. One antenna must be
either significantly fuller sized or fuller heighted at some
frequency, or suffer at another frequency as lesser sized or lesser
heighted for the same reason.

You want a 10M dipole antenna up half a wave for 160M? Is half a wave
full height? Is a 10M dipole full sized?

Describe your needs first, and then ask what would be reasonable.

73's
Richard Clark, KB7QHC

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"Richard" == Richard Clark writes:

Jack Anyone have any personal, real-life experience with a full-size,
Jack full-height HF dipole? Is it worth the cost?

Richard Hi Jack,

Richard There is no such thing. Full size and Full height for a band
Richard that has a frequencies spanning 15:1 is a contradiction. One
Richard antenna must be either significantly fuller sized or fuller
Richard heighted at some frequency, or suffer at another frequency as
Richard lesser sized or lesser heighted for the same reason.

I regret that my message was insufficiently specific. I didn't say
"all-bands HF", and I assumed that the potential respondents would
know that I knew that no single dipole is ideal for more than one band
(well, more than one *frequency*, but one band is close enough).

Richard You want a 10M dipole antenna up half a wave for 160M? Is
Richard half a wave full height? Is a 10M dipole full sized?

I am interested in people who have first-hand experience with a
full-length dipole mounted at the full height for any particular
band. A 10M dipole is full-sized if it's the full length and mounted
at the full height. Ditto for 160M.

Richard Describe your needs first, and then ask what would be
Richard reasonable.

I hope the clarification above is enough -- if not, please let me
know.

Richard 73's Richard Clark, KB7QHC

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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On Fri, 14 May 2004 13:26:45 -0700, Jack Twilley
wrote:

I am interested in people who have first-hand experience with a
full-length dipole mounted at the full height for any particular
band. A 10M dipole is full-sized if it's the full length and mounted
at the full height. Ditto for 160M.

Richard Describe your needs first, and then ask what would be
Richard reasonable.

I hope the clarification above is enough -- if not, please let me
know.

Hi Jack,

This is still inspecific. "Full height" is actually meaningless.
Let's look at a 40M dipole antenna and choose a modest 20° launch
angle to compare against.
5M over real ground:
-2dBi
10M over real ground:
1.29dBi
15M over real ground:
3.75dBi
20M over real ground:
6.27dBi
25M over real ground:
8.08dBi
30M over real ground:
7.67dBi
35M over real ground:
7.1dBi
40M over real ground:
7.52dBi

Well, let's see - best gain is NOT at any cardinal point such as
quarter wave, half wave, three quarter, nor full wave above ground ANY
of which "could" be interpreted as "full height."

This exercise is easily within the limited feature set of the free
distribution of EZNEC.

73's
Richard Clark, KB7QHC

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"Richard" =3D=3D Richard Clark writes:

Jack I am interested in people who have first-hand experience with a
Jack full-length dipole mounted at the full height for any particular
Jack band. A 10M dipole is full-sized if it's the full length and
Jack mounted at the full height. Ditto for 160M.

Richard Describe your needs first, and then ask what would be
Richard reasonable.

Jack I hope the clarification above is enough -- if not, please let
Jack me know.

Richard Hi Jack,

Richard This is still inspecific. "Full height" is actually
Richard meaningless. Let's look at a 40M dipole antenna and choose a
Richard modest 20=B0 launch angle to compare against. 5M over real
Richard ground: -2dBi 10M over real ground: 1.29dBi 15M over real
Richard ground: 3.75dBi 20M over real ground: 6.27dBi 25M over real
Richard ground: 8.08dBi 30M over real ground: 7.67dBi 35M over real
Richard ground: 7.1dBi 40M over real ground: 7.52dBi

Where did the twenty-degree launch angle come from?

Richard Well, let's see - best gain is NOT at any cardinal point such
Richard as quarter wave, half wave, three quarter, nor full wave
Richard above ground ANY of which "could" be interpreted as "full
Richard height."

I'm not familiar with twenty-degrees as any particular canonical
value. As for what I meant by "full height", one-quarter wavelength
minimum should serve.

Richard This exercise is easily within the limited feature set of the
Richard free distribution of EZNEC.

I do not doubt that your calculations are within the capabilities of
EZNEC. However, I'm more interested in real-life experience, not
computer-generated simulations.

Richard 73's Richard Clark, KB7QHC

Jack.
=2D --=20
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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On Fri, 14 May 2004 21:43:03 -0700, Jack Twilley
wrote:


I'm not familiar with twenty-degrees as any particular canonical
value. As for what I meant by "full height", one-quarter wavelength
minimum should serve.

Richard This exercise is easily within the limited feature set of the
Richard free distribution of EZNEC.

I do not doubt that your calculations are within the capabilities of
EZNEC. However, I'm more interested in real-life experience, not
computer-generated simulations.

Hi Jack,

20° serves as well as any and at least offers a basis of comparison.
This again turns to the matter of the inspecific. You cite no
particular application (DX v. NVIS) no particular band (that is
heavily swayed by ground given ground characteristics vary over
frequency) and offer a quarter wave height as "full height" which by
most standards is generally accepted as mediocre at best where half
wave height (twice full height?) offers better performance (which is
borne out in testimonial) and where higher sometimes offers worse
performance (also borne out in testimonial). Such issues are easily
isolated and compared through modeling and are consistent with
experience.

73's
Richard Clark, KB7QHC

"Jack Twilley" wrote in message
...
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"Richard" == Richard Clark writes:

Jack I am interested in people who have first-hand experience with a
Jack full-length dipole mounted at the full height for any particular
Jack band. A 10M dipole is full-sized if it's the full length and
Jack mounted at the full height. Ditto for 160M.

Richard Describe your needs first, and then ask what would be
Richard reasonable.

Jack I hope the clarification above is enough -- if not, please let
Jack me know.

Richard Hi Jack,

Richard This is still inspecific. "Full height" is actually
Richard meaningless. Let's look at a 40M dipole antenna and choose a
Richard modest 20° launch angle to compare against. 5M over real
Richard ground: -2dBi 10M over real ground: 1.29dBi 15M over real
Richard ground: 3.75dBi 20M over real ground: 6.27dBi 25M over real
Richard ground: 8.08dBi 30M over real ground: 7.67dBi 35M over real
Richard ground: 7.1dBi 40M over real ground: 7.52dBi

Where did the twenty-degree launch angle come from?

Richard Well, let's see - best gain is NOT at any cardinal point such
Richard as quarter wave, half wave, three quarter, nor full wave
Richard above ground ANY of which "could" be interpreted as "full
Richard height."

I'm not familiar with twenty-degrees as any particular canonical
value. As for what I meant by "full height", one-quarter wavelength
minimum should serve.

Richard This exercise is easily within the limited feature set of the
Richard free distribution of EZNEC.

I do not doubt that your calculations are within the capabilities of
EZNEC. However, I'm more interested in real-life experience, not
computer-generated simulations.

EZNEC will probably give you a better idea of whats going on than anecdotal
opinions. There of course is always the GiGo factor but this applies to both
computer and human analysis alike.

"Jack Twilley" wrote in message
...
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"Richard" == Richard Clark writes:

Jack Anyone have any personal, real-life experience with a full-size,
Jack full-height HF dipole? Is it worth the cost?

Richard Hi Jack,

Richard There is no such thing. Full size and Full height for a band
Richard that has a frequencies spanning 15:1 is a contradiction. One
Richard antenna must be either significantly fuller sized or fuller
Richard heighted at some frequency, or suffer at another frequency as
Richard lesser sized or lesser heighted for the same reason.

I regret that my message was insufficiently specific. I didn't say
"all-bands HF", and I assumed that the potential respondents would
know that I knew that no single dipole is ideal for more than one band
(well, more than one *frequency*, but one band is close enough).

Richard You want a 10M dipole antenna up half a wave for 160M? Is
Richard half a wave full height? Is a 10M dipole full sized?

I am interested in people who have first-hand experience with a
full-length dipole mounted at the full height for any particular
band. A 10M dipole is full-sized if it's the full length and mounted
at the full height. Ditto for 160M.

Richard Describe your needs first, and then ask what would be
Richard reasonable.

I hope the clarification above is enough -- if not, please let me
know.

Richard 73's Richard Clark, KB7QHC

Jack.
-----
Jack,

Leaving out the question of "full height", I found that a 20m dipole at 55
feet was outperforming a Junior tribander at 40 feet for distances beyond
2000 miles. Broadside to the dipole, of course.

Tam/WB2TT

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"Tarmo" == Tarmo Tammaru t-tammaru@c0mca writes:

[...]

Tarmo Leaving out the question of "full height", I found that a 20m
Tarmo dipole at 55 feet was outperforming a Junior tribander at 40
Tarmo feet for distances beyond 2000 miles. Broadside to the dipole,
Tarmo of course.

This is the kind of experience I had hoped to hear. Thank you.

Tarmo Tam/WB2TT

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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Jack Twilley wrote:
"This is the kind of experience I had hoped to hear."

A look at the vertical radiation patterns of half-wave horizontals
broadside to the antenna wire such as that shown on page 3-11 of the
19th edition of the ARRL Antenna Book provides evidence of the best
height.

A vertical angle of 50-degrees gives a first reflection target distance
of 80 to 500 miles, depending on the height of the reflecting layer,
from the graph on page 92 of Ed Laport`s "Antenna Engineering". A
vertical angle of 5-degrees gives a target distance of 700 to 2500 miles
according to the same graph.

For angles between 5 and 50-degrees, a dipole height of 1/2-wave
maximizes radiation around a vertical angle of about 30-degrees.

Best regards, Richard Harrison, KB5WZI