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dw-4

Off-Topic: Your advice/suggestion about antenna

From what I understand - solid rock below a raised vertical is not the best option for performance.
With an underlying geography of many feet of solid metamorphic rock - that would probably rule out the low angle benefits of vertical antennas.

Consequently, over the years, every 40m vertical I've ever put up has been out-performed by a dipole at .41 wavelength. I've also tried the DX-Half Square and vertical Delta Loop with the same results.

It looks to me like my only option to outperform a 40m dipole - is a tower and (at minimum) a 2EL yagi.

Would that assumption be correct?
Thanks
Duane

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Lyn WØLEN

Re: Off-Topic: Your advice/suggestion about antenna

Duane -

There are other wire antenna options that will far outperform a simple
dipole, or for that matter a 2EL yagi.

How much space do you have available?

73
Lyn, W0LEN

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of [hidden email]
Sent: Friday, March 13, 2020 10:38 AM
To: [hidden email]
Subject: [Elecraft] Off-Topic: Your advice/suggestion about antenna

From what I understand - solid rock below a raised vertical is not the best
option for performance.
With an underlying geography of many feet of solid metamorphic rock - that
would probably rule out the low angle benefits of vertical antennas.

Consequently, over the years, every 40m vertical I've ever put up has been
out-performed by a dipole at .41 wavelength. I've also tried the DX-Half
Square and vertical Delta Loop with the same results.

It looks to me like my only option to outperform a 40m dipole - is a tower
and (at minimum) a 2EL yagi.

Would that assumption be correct?
Thanks
Duane

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dw-4

Re: Off-Topic: Your advice/suggestion about antenna

Hi Lyn - thanks for the reply!
I have 3 acres of wooded land.
Its pretty much on two different levels.
The house is located on the lower level.
And from there the grade goes upwards about 30 feet- and then levels off to the second level.

Many elm trees which can support an antenna height of about 45 feet.
And I can cut through a path through them if necessary.

I have a 40m moxon pointed towards Asia at 45 feet hanging over solid rock
I've made a few DX contacts with it during the years when propagation was peaking.
But right now I think its really to low to the ground to be useful.

I'm interested in what you have in mind.
Thanks
Duane

On Fri, Mar 13, 2020, at 12:31 PM, Lyn Norstad wrote:

> Duane -
>
> There are other wire antenna options that will far outperform a simple
> dipole, or for that matter a 2EL yagi.
>
> How much space do you have available?
>
> 73
> Lyn, W0LEN
>
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of [hidden email]
> Sent: Friday, March 13, 2020 10:38 AM
> To: [hidden email]
> Subject: [Elecraft] Off-Topic: Your advice/suggestion about antenna
>
> From what I understand - solid rock below a raised vertical is not the best
> option for performance.
> With an underlying geography of many feet of solid metamorphic rock - that
> would probably rule out the low angle benefits of vertical antennas.
>
> Consequently, over the years, every 40m vertical I've ever put up has been
> out-performed by a dipole at .41 wavelength. I've also tried the DX-Half
> Square and vertical Delta Loop with the same results.
>
> It looks to me like my only option to outperform a 40m dipole - is a tower
> and (at minimum) a 2EL yagi.
>
> Would that assumption be correct?
> Thanks
> Duane
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]
>
>

Jim Brown-10

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by Lyn WØLEN

On 3/13/2020 9:31 AM, Lyn Norstad wrote:
> There are other wire antenna options that will far outperform a simple
> dipole, or for that matter a 2EL yagi.

Yes, if you want directivity. But while dipoles are simple in concept,
they are hard to beat if height is optimized.

http://k9yc.com/AntennaPlanning.pdf

73, Jim K9YC
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Lyn WØLEN

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by dw-4

Duane -

I am of the mind that the antenna is the most crucial part of any station,
and probably the most often maligned. I have made a number of presentations
to ham groups on the design and construction process involved in getting
the most bang for the buck, depending on your wants and needs (everybody's
are different).

In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet
running E-W feet, and active HOA) the goal was to have a single antenna that
would provide the best primary signal on 80 meters in a North-South
direction, while providing the best possible signal on 40 meters in an
East-West direction, consistent with the 80 meter performance and without
unduly provoking the HOA (or my XYL).

I decided on an Extended Double Zepp, cut for 3.5 MHz. That resulted in a
length of 360 feet, which worked nicely since I have 400 feet clear from the
house (West end) to a perfect tree for the far East end. And another tree
in the center for support of both the antenna and the feedline.

I am feeding it with a 160 foot length of 600 ohm "true ladder line." I can
go into more detail if this sounds like something that would work. Modeling
this antenna with EZ NEC shows a maximum theoretical gain of 4.7 dbi in both
North and South directions. With the ladder line, a dual hybrid balun and
short length of coax into the shack, my KAT500 tunes it very nicely on all
bands 160 m thru 6m.

I don't have your call so can't see where you are, but would be happy to
make other suggestions based on the coverage you seek.

73

Lyn, W0LEN

-----Original Message-----
From: [hidden email] [mailto:[hidden email]]
Sent: Friday, March 13, 2020 11:52 AM
To: Lyn Norstad; [hidden email]
Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna

Hi Lyn - thanks for the reply!

I have 3 acres of wooded land.

Its pretty much on two different levels.

The house is located on the lower level.

And from there the grade goes upwards about 30 feet- and then levels off to
the second level.

Many elm trees which can support an antenna height of about 45 feet.

And I can cut through a path through them if necessary.

I have a 40m moxon pointed towards Asia at 45 feet hanging over solid rock

I've made a few DX contacts with it during the years when propagation was
peaking.

But right now I think its really to low to the ground to be useful.

I'm interested in what you have in mind.

Thanks

Duane

On Fri, Mar 13, 2020, at 12:31 PM, Lyn Norstad wrote:

> Duane -

>

> There are other wire antenna options that will far outperform a simple

> dipole, or for that matter a 2EL yagi.

>

> How much space do you have available?

>

> 73

> Lyn, W0LEN

>

>

> -----Original Message-----

> From: [hidden email]

> [mailto:[hidden email]] On Behalf Of [hidden email]

> Sent: Friday, March 13, 2020 10:38 AM

> To: [hidden email]

> Subject: [Elecraft] Off-Topic: Your advice/suggestion about antenna

>

> From what I understand - solid rock below a raised vertical is not the
best

> option for performance.

> With an underlying geography of many feet of solid metamorphic rock - that

> would probably rule out the low angle benefits of vertical antennas.

>

> Consequently, over the years, every 40m vertical I've ever put up has been

> out-performed by a dipole at .41 wavelength. I've also tried the DX-Half

> Square and vertical Delta Loop with the same results.

>

> It looks to me like my only option to outperform a 40m dipole - is a tower

> and (at minimum) a 2EL yagi.

>

> Would that assumption be correct?

> Thanks

> Duane

>

> ______________________________________________________________

> Elecraft mailing list

> Home: http://mailman.qth.net/mailman/listinfo/elecraft

> Help: http://mailman.qth.net/mmfaq.htm

> Post: mailto:[hidden email]

>

> This list hosted by: http://www.qsl.net

> Please help support this email list: http://www.qsl.net/donate.html

> Message delivered to [hidden email]

>

>

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David Gilbert

Re: Off-Topic: Your advice/suggestion about antenna

That is certainly a perfectly viable antenna and probably a fine choice
for your needs ... but it does not "far outperform" either a dipole or
especially a 2 element yagi at the same height. (although the yagi would
of course be unidirectional). 4.7 dbi is dipole territory. You could
have gotten pretty much the same result with an E-W 80m dipole and a N-S
40m dipole fed at the same point (orthogonal fan dipole). And assuming
you used capacitors for the EDZ, dipoles are easier to build.

73,
Dave AB7E

On 3/13/2020 11:19 AM, Lyn Norstad wrote:

Rick Bates, NK7I

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by Lyn WØLEN

Duane,

I agree on both points. The antenna is THE most important element of
any station (the accepted maxim is it's 90% of the budget but most hams
are 'cheap'). The radio is useless without a decent antenna. An EDZ
can work well but the peaks and nulls vary on every band and wind in the
trees can be an issue. Height matters, a LOT too.

I also hid (in plain sight) a similar 370' EDZ (at 35') antenna IN the
HOA space (shot a wire over some oak trees) for years without it being
seen and it worked well (other than the noise floor was obscenely high,
all the time because it was urban). It absolutely ROCKED on 40M (the
noise precluded hearing much on 160M but I got 15-20 countries).

If budget is less of a concern, you might want to consider SteppIR,
starting with the 2 element Urban beam (40-6M). The only other comment
along that line is leave a LOT of headroom capacity when selecting a
rotator, they take a lot of wind abuse. There are other beam antennas
worth consideration, many are less expensive.

When I moved away from the HOA infestation area into rural with a 40 db
(average) lower noise floor, in time I went from all band (R7, dipole or
vertical) wires to a SteppIR DB36/80 (80-6M) which gave me an average of
another 10 dB of GAIN in reception (plus directivity to null noise even
further AND transmit gain too).

I bought the antenna, rotor and tower at an estate sale (SK sale),
saving many thousands of dollars. The son (a non-ham) just wanted it
all gone, I assisted ;-) so keep watch, ready to 'attack'.

The sole remaining wire is an Inverted L for 160M. I greatly prefer
this to any dipole because the one wire is not pulled/stretched between
multiple trees when it's windy (and the trees NEVER sway in sync at the
same moments). It moves precisely WITH the tree motion, it isn't
stretched or pulled. However, it's moderately deaf on 160M, I'll have
to add an RX array (RBOG or 8 square are the current considerations) yet
I'm now at 131 countries worked on 160M.

The sole sticking point remaining is my requirement that NOTHING antenna
can be seen from the house (I bought an amazing view, it came with a
house), so even with the acres I have, I'm limited to a few acres total,
further reduced by proximity to the power lines along the road.
Fortunately my neighbor (700' away) is also an HF active ham with even
more acres (same visual rule) so we're considering a shared RX array
(SDR and wifi based, which removes much of the desense issue too).

So my suggestion is that you look at the larger picture and perhaps even
start fresh, not re-modify the original plans (make it a Revolution, not
just an evolution). Part of my move (escape to) here was just for that
reason, to start with a fresh station based on simplicity of operation
(which takes a LOT of planning and work to obtain; in a couple years,
it'll be there, I hope.)

GL,
Rick NK7I

On 3/13/2020 11:19 AM, Lyn Norstad wrote:

> Duane -
>
>
>
> I am of the mind that the antenna is the most crucial part of any station,
> and probably the most often maligned. I have made a number of presentations
> to ham groups on the design and construction process involved in getting
> the most bang for the buck, depending on your wants and needs (everybody's
> are different).
>
>
>
> In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet
> running E-W feet, and active HOA) the goal was to have a single antenna that
> would provide the best primary signal on 80 meters in a North-South
> direction, while providing the best possible signal on 40 meters in an
> East-West direction, consistent with the 80 meter performance and without
> unduly provoking the HOA (or my XYL).
>
>
>
> I decided on an Extended Double Zepp, cut for 3.5 MHz. That resulted in a
> length of 360 feet, which worked nicely since I have 400 feet clear from the
> house (West end) to a perfect tree for the far East end. And another tree
> in the center for support of both the antenna and the feedline.
>
>
>
> I am feeding it with a 160 foot length of 600 ohm "true ladder line." I can
> go into more detail if this sounds like something that would work. Modeling
> this antenna with EZ NEC shows a maximum theoretical gain of 4.7 dbi in both
> North and South directions. With the ladder line, a dual hybrid balun and
> short length of coax into the shack, my KAT500 tunes it very nicely on all
> bands 160 m thru 6m.
>
>
>
> I don't have your call so can't see where you are, but would be happy to
> make other suggestions based on the coverage you seek.
>
>
>
> 73
>
> Lyn, W0LEN
>
>
>
>
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]]
> Sent: Friday, March 13, 2020 11:52 AM
> To: Lyn Norstad; [hidden email]
> Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna
>
>
>
> Hi Lyn - thanks for the reply!
>
> I have 3 acres of wooded land.
>
> Its pretty much on two different levels.
>
> The house is located on the lower level.
>
> And from there the grade goes upwards about 30 feet- and then levels off to
> the second level.
>
>
>
> Many elm trees which can support an antenna height of about 45 feet.
>
> And I can cut through a path through them if necessary.
>
>
>
> I have a 40m moxon pointed towards Asia at 45 feet hanging over solid rock
>
> I've made a few DX contacts with it during the years when propagation was
> peaking.
>
> But right now I think its really to low to the ground to be useful.
>
>
>
> I'm interested in what you have in mind.
>
> Thanks
>
> Duane
>
>
>
> On Fri, Mar 13, 2020, at 12:31 PM, Lyn Norstad wrote:
>
>> Duane -
>> There are other wire antenna options that will far outperform a simple
>> dipole, or for that matter a 2EL yagi.
>> How much space do you have available?
>> 73
>> Lyn, W0LEN
>> -----Original Message-----
>> From: [hidden email]
>> [mailto:[hidden email]] On Behalf Of [hidden email]
>> Sent: Friday, March 13, 2020 10:38 AM
>> To: [hidden email]
>> Subject: [Elecraft] Off-Topic: Your advice/suggestion about antenna
>> From what I understand - solid rock below a raised vertical is not the
> best
>
>> option for performance.
>> With an underlying geography of many feet of solid metamorphic rock - that
>> would probably rule out the low angle benefits of vertical antennas.
>> Consequently, over the years, every 40m vertical I've ever put up has been
>> out-performed by a dipole at .41 wavelength. I've also tried the DX-Half
>> Square and vertical Delta Loop with the same results.
>> It looks to me like my only option to outperform a 40m dipole - is a tower
>> and (at minimum) a 2EL yagi.
>> Would that assumption be correct?
>> Thanks
>> Duane
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>> Message delivered to [hidden email]
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
> Message delivered to [hidden email]

Lyn WØLEN

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by David Gilbert

Dave -

I actually do consider 4.7 dbi as "far outperforming" 2.14 dbi (ordinary dipole).

And since cost is an issue for some of us (along with HOA restrictions), I rejected the idea of getting a couple extra dbi at the cost of many thousands of dollars. And adding a N-S 40m dipole fed at the same point would have required either traversing my neighbor’s yard, or erecting a 2 towers … neither of which is feasible.

And forget the logistics of erecting a 2 element beam for 80 meters (see OptiBeam OB2-80+ with 74 foot elements on a 36 foot boom), tower and rotor for that monster.

We have a commercial (HST) shortwave station a few miles away that runs a 20kw transmitter on various 7 - 10 MHz frequencies into an 18 dbi gain "curtain" antenna aimed over the pole to Europe. Their beam width is 38º. Ten curtains could be hung using relatively inexpensive towers or masts spaced at 36º in a circle. The 20kw input results in an ERP of 808 KW, according to their FCC license, at an extremely low angle of radiation, and very low maintenance.

That would actually be my first choice.

73

Lyn, W0LEN

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of David Gilbert
Sent: Friday, March 13, 2020 1:39 PM
To: [hidden email]
Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna

That is certainly a perfectly viable antenna and probably a fine choice

for your needs ... but it does not "far outperform" either a dipole or

especially a 2 element yagi at the same height. (although the yagi would

of course be unidirectional). 4.7 dbi is dipole territory. You could

have gotten pretty much the same result with an E-W 80m dipole and a N-S

40m dipole fed at the same point (orthogonal fan dipole). And assuming

you used capacitors for the EDZ, dipoles are easier to build.

73,

Dave AB7E

On 3/13/2020 11:19 AM, Lyn Norstad wrote:

> Duane -

>

>

>

> I am of the mind that the antenna is the most crucial part of any station,

> and probably the most often maligned. I have made a number of presentations

> to ham groups on the design and construction process involved in getting

> the most bang for the buck, depending on your wants and needs (everybody's

> are different).

>

>

>

> In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet

> running E-W feet, and active HOA) the goal was to have a single antenna that

> would provide the best primary signal on 80 meters in a North-South

> direction, while providing the best possible signal on 40 meters in an

> East-West direction, consistent with the 80 meter performance and without

> unduly provoking the HOA (or my XYL).

>

>

>

> I decided on an Extended Double Zepp, cut for 3.5 MHz. That resulted in a

> length of 360 feet, which worked nicely since I have 400 feet clear from the

> house (West end) to a perfect tree for the far East end. And another tree

> in the center for support of both the antenna and the feedline.

>

>

>

> I am feeding it with a 160 foot length of 600 ohm "true ladder line." I can

> go into more detail if this sounds like something that would work. Modeling

> this antenna with EZ NEC shows a maximum theoretical gain of 4.7 dbi in both

> North and South directions. With the ladder line, a dual hybrid balun and

> short length of coax into the shack, my KAT500 tunes it very nicely on all

> bands 160 m thru 6m.

>

>

>

> I don't have your call so can't see where you are, but would be happy to

> make other suggestions based on the coverage you seek.

>

>

>

> 73

>

> Lyn, W0LEN

>

>

______________________________________________________________

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Jim Brown-10

Re: Off-Topic: Your advice/suggestion about antenna

On 3/13/2020 12:49 PM, Lyn Norstad wrote:
> I actually do consider 4.7 dbi as "far outperforming" 2.14 dbi (ordinary dipole).

It depends on what you want to achieve. The antenna you describe is a
very old and well accepted design. It's like a beam with a fixed
direction. No question that 2.6 dB can matter under marginal conditions.
I have a 2-el wire 80M Yagi fixed on about 45 deg az that I can reverse
to VK/ZL, which modeling shows gives me about that directivity.

HOWEVER -- in this applications note, I showed that raising a 40M or 20M
dipole by 15 feet will also increase gain at low angles by about 2.6 dB.
See Figs 33 and 41, and the associated text. Doing this uses height to
modify directivity in the vertical plane, without narrowing the
horizontal beamwidth.

http://k9yc.com/AntennaPlanning.pdf

In the same app note, I also showed that mounting an HF vertical on a
roof reduces ground losses and increases gain at lower vertical angles
(below 30-40 degrees) than ground-mounting it. The differences show up
for all soil conditions (except sea water), but are most pronounced for
poor soil.

I showed that the gain of vertical antennas is strongly affected by soil
conductivity, while horizontal antennas are not, but are strongly
affected by mounting height.

And finally, I disproved the myth that antennas must be low for NVIS,
that 75 electrical degrees is optimum, and that raising it to 120
degrees reduces high angle radiation by only 1 dB while increasing low
angle radiation by 6 dB.

Antennas are the component of our stations that are most strongly
dependent on operator goals, real estate, the availability (and the
cost) of suitable skyhooks or towers, their ability to reject local
noise, and restrictions like HOAs, neighbors, and XYLs. No single
antenna is best for all stations or operators. Antennas I can rig here
in my redwood forest would be impossible on the city lot I owned in
Chicago. :)

73, Jim K9YC

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Lyn WØLEN

Re: Off-Topic: Your advice/suggestion about antenna

Jim -

Your antenna research is impressive. I have downloaded the PDF and will
spend some time studying it. Thanks.

One question I have relates to NVIS. In the case of my 80 meter EDZ, the
plan was to make it workable for NVIS operation. It has succeeded in that
regard very nicely in that I can cover the entire state of Illinois (which
is primarily a N-S pattern) very well on both 80 and 160. We operate a
state wide ARES/RACES net on 80m, but there has been some fear that as
propagation continues to worsen for a period, the MUF for NVIS will require
a higher frequency than non-NVIS and one that actually approaches the MOF at
that time - due to the angle of radiation. In other words, using an NVIS
antenna when the MUF is 4.0 MHz might actually require an MUF of 12 - 13 MHz
which would be closer to the MOF at that same point in time.

Have you observed that at any extremely low spot in the cycle?

We have seemingly remedied that by setting up and operating a successful
160m net and passing digital traffic.

73
Lyn, W0LEN

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Jim Brown
Sent: Friday, March 13, 2020 4:03 PM
To: [hidden email]
Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna

On 3/13/2020 12:49 PM, Lyn Norstad wrote:
> I actually do consider 4.7 dbi as "far outperforming" 2.14 dbi (ordinary
dipole).

It depends on what you want to achieve. The antenna you describe is a
very old and well accepted design. It's like a beam with a fixed
direction. No question that 2.6 dB can matter under marginal conditions.
I have a 2-el wire 80M Yagi fixed on about 45 deg az that I can reverse
to VK/ZL, which modeling shows gives me about that directivity.

HOWEVER -- in this applications note, I showed that raising a 40M or 20M
dipole by 15 feet will also increase gain at low angles by about 2.6 dB.
See Figs 33 and 41, and the associated text. Doing this uses height to
modify directivity in the vertical plane, without narrowing the
horizontal beamwidth.

http://k9yc.com/AntennaPlanning.pdf

In the same app note, I also showed that mounting an HF vertical on a
roof reduces ground losses and increases gain at lower vertical angles
(below 30-40 degrees) than ground-mounting it. The differences show up
for all soil conditions (except sea water), but are most pronounced for
poor soil.

I showed that the gain of vertical antennas is strongly affected by soil
conductivity, while horizontal antennas are not, but are strongly
affected by mounting height.

And finally, I disproved the myth that antennas must be low for NVIS,
that 75 electrical degrees is optimum, and that raising it to 120
degrees reduces high angle radiation by only 1 dB while increasing low
angle radiation by 6 dB.

Antennas are the component of our stations that are most strongly
dependent on operator goals, real estate, the availability (and the
cost) of suitable skyhooks or towers, their ability to reject local
noise, and restrictions like HOAs, neighbors, and XYLs. No single
antenna is best for all stations or operators. Antennas I can rig here
in my redwood forest would be impossible on the city lot I owned in
Chicago. :)

73, Jim K9YC

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David Gilbert

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by Lyn WØLEN

Lyn,

A dipole over ground has considerably more than 2.14 dbi maximum gain,
and since you said you had a tree in the middle I assumed (probably
incorrectly) that it was enough in the middle to allow a 40m dipole to
fit crossways your lot to other trees. If that isn't the case, OK.

You didn't say whether your model that gave you 4.7 dbi for the EDZ was
a free space figure (and I'm too lazy to model it myself now to check),
but if so yes ... there would be at least a 2.5 db benefit to the EDZ.
I've done my own tests to demonstrate the clear advantage that even 2 db
can provide (see http://www.ab7e.com/weak_signal/mdd.html), but I still
wouldn't call that "far outperforming".

And who said anything about putting up a rotating yagi?? Your EDZ is
not rotatable so why eliminate a wire yagi from consideration because it
isn't. As I said, you do have to settle for unidirectionality but your
original comment was that other wire options would beat the yagi for
gain ... they don't.

I've read your reply three times now and still don't understand what
20KW into a ten curtain array has anything to do with this discussion.

Dave,
AB7E

On 3/13/2020 12:49 PM, Lyn Norstad wrote:

>
> Dave -
>
> I actually /do/ consider 4.7 dbi as "far outperforming" 2.14 dbi
> (ordinary dipole).
>
> And since cost is an issue for some of us (along with HOA
> restrictions), I rejected the idea of getting a couple extra dbi at
> the cost of many thousands of dollars. And adding a N-S 40m dipole
> fed at the same point would have required either traversing my
> neighbor’s yard, or erecting a 2 towers … neither of which is feasible.
>
> And forget the logistics of erecting a 2 element beam for 80 meters
> (see OptiBeam OB2-80+ with 74 foot elements on a 36 foot boom), tower
> and rotor for that monster.
>
> We have a commercial (HST) shortwave station a few miles away that
> runs a 20kw transmitter on various 7 - 10 MHz frequencies into an 18
> dbi gain "curtain" antenna aimed over the pole to Europe. Their beam
> width is 38º. Ten curtains could be hung using relatively inexpensive
> towers or masts spaced at 36º in a circle. The 20kw input results in
> an ERP of 808 KW, according to their FCC license, at an extremely low
> angle of radiation, and very low maintenance.
>
> That would actually be my first choice.
>
> 73
>
> Lyn, W0LEN
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of David Gilbert
> Sent: Friday, March 13, 2020 1:39 PM
> To: [hidden email]
> Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna
>
> That is certainly a perfectly viable antenna and probably a fine choice
>
> for your needs ... but it does not "far outperform" either a dipole or
>
> especially a 2 element yagi at the same height. (although the yagi would
>
> of course be unidirectional). 4.7 dbi is dipole territory. You could
>
> have gotten pretty much the same result with an E-W 80m dipole and a N-S
>
> 40m dipole fed at the same point (orthogonal fan dipole). And assuming
>
> you used capacitors for the EDZ, dipoles are easier to build.
>
> 73,
>
> Dave AB7E
>
> On 3/13/2020 11:19 AM, Lyn Norstad wrote:
>
> > Duane -
>
> >
>
> >
>
> >
>
> > I am of the mind that the antenna is the most crucial part of any
> station,
>
> > and probably the most often maligned. I have made a number of
> presentations
>
> > to ham groups on the design and construction process involved in
> getting
>
> > the most bang for the buck, depending on your wants and needs
> (everybody's
>
> > are different).
>
> >
>
> >
>
> >
>
> > In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet
>
> > running E-W feet, and active HOA) the goal was to have a single
> antenna that
>
> > would provide the best primary signal on 80 meters in a North-South
>
> > direction, while providing the best possible signal on 40 meters in an
>
> > East-West direction, consistent with the 80 meter performance and
> without
>
> > unduly provoking the HOA (or my XYL).
>
> >
>
> >
>
> >
>
> > I decided on an Extended Double Zepp, cut for 3.5 MHz. That
> resulted in a
>
> > length of 360 feet, which worked nicely since I have 400 feet clear
> from the
>
> > house (West end) to a perfect tree for the far East end. And
> another tree
>
> > in the center for support of both the antenna and the feedline.
>
> >
>
> >
>
> >
>
> > I am feeding it with a 160 foot length of 600 ohm "true ladder
> line." I can
>
> > go into more detail if this sounds like something that would work.
> Modeling
>
> > this antenna with EZ NEC shows a maximum theoretical gain of 4.7 dbi
> in both
>
> > North and South directions. With the ladder line, a dual hybrid
> balun and
>
> > short length of coax into the shack, my KAT500 tunes it very nicely
> on all
>
> > bands 160 m thru 6m.
>
> >
>
> >
>
> >
>
> > I don't have your call so can't see where you are, but would be happy to
>
> > make other suggestions based on the coverage you seek.
>
> >
>
> >
>
> >
>
> > 73
>
> >
>
> > Lyn, W0LEN
>
> >
>
> >
>
> ______________________________________________________________
>
> Elecraft mailing list
>
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>
> Help: http://mailman.qth.net/mmfaq.htm
>
> Post: mailto:[hidden email]
>
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>
> Please help support this email list: http://www.qsl.net/donate.html
>
> Message delivered to [hidden email]
>

Bob McGraw - K4TAX

Off-Topic: Your advice/suggestion about antenna

Just to set the record straight.

dBi = dB(isotropic) – the forward gain of an antenna
<https://en.wikipedia.org/wiki/Antenna_gain> compared with the
hypothetical isotropic antenna
<https://en.wikipedia.org/wiki/Isotropic_antenna>, which uniformly
distributes energy in all directions. Linear polarization
<https://en.wikipedia.org/wiki/Linear_polarization> of the EM field is
assumed unless noted otherwise.

dBd = dB(dipole) – the forward gain of an antenna
<https://en.wikipedia.org/wiki/Antenna_(electronics)> compared with a
half-wave dipole antenna <https://en.wikipedia.org/wiki/Dipole_antenna>.
0 dBd = 2.15 dBi

dBiC = dB(isotropic circular) – the forward gain of an antenna compared
to a circularly polarized
<https://en.wikipedia.org/wiki/Circular_polarization> isotropic antenna.
There is no fixed conversion rule between dBiC and dBi, as it depends on
the receiving antenna and the field polarization.

dBq = dB(quarterwave) – the forward gain of an antenna compared to a
quarter wavelength whip. Rarely used, except in some marketing material.
0 dBq = −0.85 dBi

dBsm = dB(m²) – decibel relative to one square meter: measure of the
antenna effective area
<https://en.wikipedia.org/wiki/Antenna_effective_area>.]
<https://en.wikipedia.org/wiki/Decibel#cite_note-60>

dBm−1 =dB(m−1) – decibel relative to reciprocal of meter: measure of the
antenna factor <https://en.wikipedia.org/wiki/Antenna_factor>.

73

Bob, K4TAX

On 3/13/2020 6:08 PM, David Gilbert wrote:

>
> Lyn,
>
> A dipole over ground has considerably more than 2.14 dbi maximum gain,
> and since you said you had a tree in the middle I assumed (probably
> incorrectly) that it was enough in the middle to allow a 40m dipole to
> fit crossways your lot to other trees. If that isn't the case, OK.
>
> You didn't say whether your model that gave you 4.7 dbi for the EDZ
> was a free space figure (and I'm too lazy to model it myself now to
> check), but if so yes ... there would be at least a 2.5 db benefit to
> the EDZ. I've done my own tests to demonstrate the clear advantage
> that even 2 db can provide (see
> http://www.ab7e.com/weak_signal/mdd.html), but I still wouldn't call
> that "far outperforming".
>
> And who said anything about putting up a rotating yagi?? Your EDZ is
> not rotatable so why eliminate a wire yagi from consideration because
> it isn't. As I said, you do have to settle for unidirectionality but
> your original comment was that other wire options would beat the yagi
> for gain ... they don't.
>
> I've read your reply three times now and still don't understand what
> 20KW into a ten curtain array has anything to do with this discussion.
>
> Dave,
> AB7E
>
>
>
> On 3/13/2020 12:49 PM, Lyn Norstad wrote:
>>
>> Dave -
>>
>> I actually /do/ consider 4.7 dbi as "far outperforming" 2.14 dbi
>> (ordinary dipole).
>>
>> And since cost is an issue for some of us (along with HOA
>> restrictions), I rejected the idea of getting a couple extra dbi at
>> the cost of many thousands of dollars. And adding a N-S 40m dipole
>> fed at the same point would have required either traversing my
>> neighbor’s yard, or erecting a 2 towers … neither of which is feasible.
>>
>> And forget the logistics of erecting a 2 element beam for 80 meters
>> (see OptiBeam OB2-80+ with 74 foot elements on a 36 foot boom), tower
>> and rotor for that monster.
>>
>> We have a commercial (HST) shortwave station a few miles away that
>> runs a 20kw transmitter on various 7 - 10 MHz frequencies into an 18
>> dbi gain "curtain" antenna aimed over the pole to Europe. Their beam
>> width is 38º. Ten curtains could be hung using relatively
>> inexpensive towers or masts spaced at 36º in a circle. The 20kw
>> input results in an ERP of 808 KW, according to their FCC license, at
>> an extremely low angle of radiation, and very low maintenance.
>>
>> That would actually be my first choice.
>>
>> 73
>>
>> Lyn, W0LEN
>>
>> -----Original Message-----
>> From: [hidden email]
>> [mailto:[hidden email]] On Behalf Of David Gilbert
>> Sent: Friday, March 13, 2020 1:39 PM
>> To: [hidden email]
>> Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna
>>
>> That is certainly a perfectly viable antenna and probably a fine choice
>>
>> for your needs ... but it does not "far outperform" either a dipole or
>>
>> especially a 2 element yagi at the same height. (although the yagi would
>>
>> of course be unidirectional). 4.7 dbi is dipole territory. You could
>>
>> have gotten pretty much the same result with an E-W 80m dipole and a N-S
>>
>> 40m dipole fed at the same point (orthogonal fan dipole). And assuming
>>
>> you used capacitors for the EDZ, dipoles are easier to build.
>>
>> 73,
>>
>> Dave AB7E
>>
>> On 3/13/2020 11:19 AM, Lyn Norstad wrote:
>>
>> > Duane -
>>
>> >
>>
>> >
>>
>> >
>>
>> > I am of the mind that the antenna is the most crucial part of any
>> station,
>>
>> > and probably the most often maligned. I have made a number of
>> presentations
>>
>> > to ham groups on the design and construction process involved in
>> getting
>>
>> > the most bang for the buck, depending on your wants and needs
>> (everybody's
>>
>> > are different).
>>
>> >
>>
>> >
>>
>> >
>>
>> > In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet
>>
>> > running E-W feet, and active HOA) the goal was to have a single
>> antenna that
>>
>> > would provide the best primary signal on 80 meters in a North-South
>>
>> > direction, while providing the best possible signal on 40 meters in an
>>
>> > East-West direction, consistent with the 80 meter performance and
>> without
>>
>> > unduly provoking the HOA (or my XYL).
>>
>> >
>>
>> >
>>
>> >
>>
>> > I decided on an Extended Double Zepp, cut for 3.5 MHz. That
>> resulted in a
>>
>> > length of 360 feet, which worked nicely since I have 400 feet clear
>> from the
>>
>> > house (West end) to a perfect tree for the far East end. And
>> another tree
>>
>> > in the center for support of both the antenna and the feedline.
>>
>> >
>>
>> >
>>
>> >
>>
>> > I am feeding it with a 160 foot length of 600 ohm "true ladder
>> line." I can
>>
>> > go into more detail if this sounds like something that would work.
>> Modeling
>>
>> > this antenna with EZ NEC shows a maximum theoretical gain of 4.7
>> dbi in both
>>
>> > North and South directions. With the ladder line, a dual hybrid
>> balun and
>>
>> > short length of coax into the shack, my KAT500 tunes it very nicely
>> on all
>>
>> > bands 160 m thru 6m.
>>
>> >
>>
>> >
>>
>> >
>>
>> > I don't have your call so can't see where you are, but would be
>> happy to
>>
>> > make other suggestions based on the coverage you seek.
>>
>> >
>>
>> >
>>
>> >
>>
>> > 73
>>
>> >
>>
>> > Lyn, W0LEN
>>
>> >
>>
>> >
>>
>> ______________________________________________________________
>>
>> Elecraft mailing list
>>
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>>
>> Help: http://mailman.qth.net/mmfaq.htm
>>
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>>
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>> Message delivered to [hidden email]
>>
>
> ______________________________________________________________
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Jim Brown-10

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by Lyn WØLEN

On 3/13/2020 3:05 PM, Lyn Norstad wrote:

Hi Lyn,

IL is a state I know fairly well, having spent 41 years in Chicago and
one in Cairo.

I don't work nets like you do, but I do a lot of contesting, including
80 and 160M, and if you're paying attention, can teach a lot about
propagation. I have several interesting observations about 160M. First,
ANY horizontal wire that we can rig is electrically very low, so ground
losses are high.

When I first moved to NorCal in 2006, I had an 80 ft Tee vertical with a
lot of radials and a dipole at about 110 ft. During contests, I switched
between them a lot. The dipole rarely "won." 160M contests start at 2PM
local, so our first 2.5 hours are in broad daylight. During those hours,
I soon learned that, running legal limit CW, I could reliably work out
to 800 miles or so on the vertical, but not even get "QRZ?" on the
dipole. Clearly, there's a difference between horizontal and vertical
propagation under these conditions! When that 150 dipole bit the dust in
a major storm several years later, I didn't bother to restore it.

In addition, the bigger stations as far east as VE3 and W8/W9 are solid
copy here as early as 3:15 pm local, but are almost impossible to work.
At least two reasons are at play: 1) they're using RX antennas aimed to
EU for more points per QSO and for multipliers; and 2) they have noise
propagated from the east, while I have mostly local noise.

While I haven't really answered your question, I do suggest that you try
to rig some sort of top-loaded vertical with as much of a counterpoise
as you can manage. Some years ago, I put together an app note on 160M
antennas and counterpoise/radial systems, all of it the summary of very
good work by others. All the advice for 160 scales for 80M. Two of the
more interesting ideas are K2AV's folded counterpoise and Rob Sherwood's
improvised ground screen.

http://k9yc.com/160MPacificon.pdf

This slide deck shows what I did in Chicago. The antennas I used there
are shown beginning on page 10. I found that the 80/40 loaded dipole
worked on 160 as a Tee vertical (fed with vintage 75 ohm "KW twinlead),
and it worked better fed as a vertical on 80 than it did fed as a
dipole. Thanks to the loading coils and the length of the feedline, it
was pretty easy to load on both bands. That discussion starts on page
30. My counterpoise was a wrought iron fence that ran around my front
yard. :) That antenna had no problem working anyone within 800-1000 miles.

http://k9yc.com/LimitedSpaceAntennasPPT.pdf

73, Jim K9YC

>
> One question I have relates to NVIS. In the case of my 80 meter EDZ, the
> plan was to make it workable for NVIS operation. It has succeeded in that
> regard very nicely in that I can cover the entire state of Illinois (which
> is primarily a N-S pattern) very well on both 80 and 160. We operate a
> state wide ARES/RACES net on 80m, but there has been some fear that as
> propagation continues to worsen for a period, the MUF for NVIS will require
> a higher frequency than non-NVIS and one that actually approaches the MOF at
> that time - due to the angle of radiation. In other words, using an NVIS
> antenna when the MUF is 4.0 MHz might actually require an MUF of 12 - 13 MHz
> which would be closer to the MOF at that same point in time.
>
> Have you observed that at any extremely low spot in the cycle?
>
> We have seemingly remedied that by setting up and operating a successful
> 160m net and passing digital traffic.

Don Wilhelm

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by David Gilbert

If I recall correctly, the original question in this thread was about
the effectiveness of radials over rocky ground. We have gone far astray
from that consideration. I am trying to bring it back to 'ground zero'.

As I recall, the question was about a vertical whose feedpoint was above
the ground - rocky or not.

Let me add some conceptual thoughts.

Does anyone remember the Ground Plane vertical that was popular back in
the 1960s and 1970s (and is still commonly used on VHF today)? A 1/4
wavelength vertical radiator with usually 4 1/4 wavelength radials from
the base. It was often mounted on a roof, and the radials sloped
downward along the roof providing a feedpoint impedance near 50 ohms as
opposed to 35 ohms if the radials are perpendicular to the vertical member.

That antenna has a nice low angle of radiation, which is good for far
away stations. A dipole has a higher angle of radiation, and will
outperform the vertical at near-in distances. A high dipole (at least 1
wavelength high) will also have equal low angle radiation to the vertical.

To work effectively, the radials must be arranged symmetrically, so each
pair will cancel the horizontally polarized radiation. Actually only 2
radials are required for that, but they must be arranged 180 degrees
from each other. For best performance, the radials should be tuned to
the center frequency of interest - just like tuning a dipole.

This is what is known today as a vertical with raised (or elevated)
radials. It is ground independent in contrast to a typical vertical
with buried radials which is quite dependent on ground conductivity.

In comparing a vertical with a dipole, remember that a good vertical has
its best radiation at a low takeoff angle, while a dipole will have its
best radiation at a much higher angle. Listening tests will make the
dipole have much better performance when there are a lot of stations in
the 400 to 800 mile radius of the station, while the vertical will
'reach out further' while suppressing the strength of the nearby signals.

So all this talk about how many dBi is nonsensical unless a specific
angle of radiation is being stated as well. A good vertical has better
low angle radiation than a dipole, and rejects high angle signals. A
dipole that is low in terms of wavelength has a high angle component of
radiation.

That means to me that a dipole mounted at a modest height for 160, 80,
and 40 will provide local as well as moderately distant contacts easily.
A proper vertical will provide more DX contacts, and weaken the
receive signals for more close-in stations - it is all in the angle of
radiation - how many miles does the signal travel before it is reflected
by the ionosphere? It is all a matter of physics and geometry.

73,
Don W3FPR

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Jim Brown-10

Re: Off-Topic: Your advice/suggestion about antenna

That's a bit oversimplified, Don, because of the very strong effect of
soil conductivity and mounting height on the performance of a vertically
polarized antenna. That's addressed in the app note I referenced earlier.

http://k9yc.com/AntennaPlanning.pdf

And this one.

http://k9yc.com/43FtVertical.pdf

Mounting height and soil conductivity move the lobes around AND vary the
ground losses. There are many combinations that can cause a vertical to
be stronger at high angles (45-60 degrees) than a low dipole. The one
characteristic of verticals is that their radiation goes to zero
straight up.

You don't see these things clearly until you plot patterns for antennas
being compared on the same graph, as I did in those links.

73, Jim K9YC

on On 3/13/2020 6:44 PM, Don Wilhelm wrote:
> That means to me that a dipole mounted at a modest height for 160, 80,
> and 40 will provide local as well as moderately distant contacts easily.
> A proper vertical will provide more DX contacts, and weaken the
> receive signals for more close-in stations - it is all in the angle of
> radiation - how many miles does the signal travel before it is reflected
> by the ionosphere? It is all a matter of physics and geometry.

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Edward R Cole

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by dw-4

As far as a vertical mounted on solid rock, ever heard of
radials? Almost all analysis shows angle lowering by copious
addition of radials to a vertical. I suggest You find the QEX
articles written By Rudy-N6LF which studied radials
thoroughly. Even with very short radials my 630m inverted-L gets out
over 2500-miles (at times0.

Another antenna I discovered that I really liked is the Moxon. I has
the gain of a two-element yagi but works well in almost all
directions (point it toward your favorite direction). I ran a 6m
moxon at 0.7 wavelength height in CO during a contest and worked all
four borders of the lower 48 states using 150w. Worked quite well
without turning it (pointed east).

At home I use an inverted-V with center at 40-foot and tails at
20-foot. Works out to 800 miles very well; works West Coast
(3000-miles) from AK in BP40 with 100w.

73, Ed - KL7UW
http://www.kl7uw.com
Dubus-NA Business mail:
[hidden email]

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David Gilbert

Re: Off-Topic: Your advice/suggestion about antenna

There is some erroneous information here, as well as in Don W3FPR's post.

Radials, whether buried or raised, only affect near field ground return
currents. You cannot improve ground conductivity beyond the radials,
and the strength of the low angle lobe is directly affected by the
ground conductivity several wavelengths distant from the vertical. This
is well established science and you can clearly see the effect in simple
models.

Dave AB7E

On 3/13/2020 11:14 PM, Edward R Cole wrote:

> As far as a vertical mounted on solid rock, ever heard of radials?
> Almost all analysis shows angle lowering by copious addition of
> radials to a vertical. I suggest You find the QEX articles written
> By Rudy-N6LF which studied radials thoroughly. Even with very short
> radials my 630m inverted-L gets out over 2500-miles (at times0.
>
> Another antenna I discovered that I really liked is the Moxon. I has
> the gain of a two-element yagi but works well in almost all directions
> (point it toward your favorite direction). I ran a 6m moxon at 0.7
> wavelength height in CO during a contest and worked all four borders
> of the lower 48 states using 150w. Worked quite well without turning
> it (pointed east).
>
> At home I use an inverted-V with center at 40-foot and tails at
> 20-foot. Works out to 800 miles very well; works West Coast
> (3000-miles) from AK in BP40 with 100w.
>
> 73, Ed - KL7UW
> http://www.kl7uw.com
> Dubus-NA Business mail:
> [hidden email]

Jim Brown-10

Re: Off-Topic: Your advice/suggestion about antenna

Right.

73, Jim K9YC

On 3/14/2020 12:09 AM, David Gilbert wrote:
> There is some erroneous information here, as well as in Don W3FPR's post.
>
> Radials, whether buried or raised, only affect near field ground return
> currents. You cannot improve ground conductivity beyond the radials,
> and the strength of the low angle lobe is directly affected by the
> ground conductivity several wavelengths distant from the vertical. This
> is well established science and you can clearly see the effect in simple
> models.

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George Thornton

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by Rick Bates, NK7I

I would add the following comments.

You can easily reach the point of obsession with antennas, and some of the choices involve heavy expense, tons of room, tolerant neighbors and a lot of maintenance.

I think the Yagi antennas are among the best choices, by their nature they concentrate strength in one direction. As a horizontal polarized antenna they are less affected by noise than vertically polarized antennas. They also heavily concentrate power in one direction, and they naturally filter out interfering signals coming from the sides. They are fun and work really well.

I am a SteppIr fan and their antennas are well built and reliable. I have done wonders with a 3 element trombone version using just 100 watts in an urban location with the antenna mounted on a nine foot rooftop tower.

Yagis do involve heavy wind loading and they do require a sturdy tower type base of support and a substantial rotor.

Size is always better but with size also comes expense, hard work and maintenance. Looking at SteppIr, a three element Yagi is light enough to be raised by hand with a small crew of two or three people using a gin pole. The larger SteppIrs weigh around 250 lbs and you will need a boom truck.

There is a lot of wind loading with Yagis and wind storms can cause a lot of damage. Your rotor needs to be pretty sturdy; even the three elements need a Tailtwister or better. You have to go really heavy duty with the big boys and that costs a lot more money.

Our Mike and Key field day site sports a wide variety of Yagis. I run the GOTA station with a small three element trapped Yagi that I can support on a temporary tripod mount made out of Army surplus aluminum tubes. The 40 meter Yagi is made of wire, six elements with what looks like a 100 ft boom, erected on lines run between trees.

-----Original Message-----
From: [hidden email] <[hidden email]> On Behalf Of Rick Bates, NK7I
Sent: Friday, March 13, 2020 12:02 PM
To: [hidden email]
Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about antenna

Duane,

I agree on both points. The antenna is THE most important element of any station (the accepted maxim is it's 90% of the budget but most hams are 'cheap'). The radio is useless without a decent antenna. An EDZ can work well but the peaks and nulls vary on every band and wind in the trees can be an issue. Height matters, a LOT too.

I also hid (in plain sight) a similar 370' EDZ (at 35') antenna IN the HOA space (shot a wire over some oak trees) for years without it being seen and it worked well (other than the noise floor was obscenely high, all the time because it was urban). It absolutely ROCKED on 40M (the noise precluded hearing much on 160M but I got 15-20 countries).

If budget is less of a concern, you might want to consider SteppIR, starting with the 2 element Urban beam (40-6M). The only other comment along that line is leave a LOT of headroom capacity when selecting a rotator, they take a lot of wind abuse. There are other beam antennas worth consideration, many are less expensive.

When I moved away from the HOA infestation area into rural with a 40 db
(average) lower noise floor, in time I went from all band (R7, dipole or
vertical) wires to a SteppIR DB36/80 (80-6M) which gave me an average of another 10 dB of GAIN in reception (plus directivity to null noise even further AND transmit gain too).

I bought the antenna, rotor and tower at an estate sale (SK sale), saving many thousands of dollars. The son (a non-ham) just wanted it all gone, I assisted ;-) so keep watch, ready to 'attack'.

The sole remaining wire is an Inverted L for 160M. I greatly prefer this to any dipole because the one wire is not pulled/stretched between multiple trees when it's windy (and the trees NEVER sway in sync at the same moments). It moves precisely WITH the tree motion, it isn't stretched or pulled. However, it's moderately deaf on 160M, I'll have to add an RX array (RBOG or 8 square are the current considerations) yet I'm now at 131 countries worked on 160M.

The sole sticking point remaining is my requirement that NOTHING antenna can be seen from the house (I bought an amazing view, it came with a house), so even with the acres I have, I'm limited to a few acres total, further reduced by proximity to the power lines along the road. Fortunately my neighbor (700' away) is also an HF active ham with even more acres (same visual rule) so we're considering a shared RX array (SDR and wifi based, which removes much of the desense issue too).

So my suggestion is that you look at the larger picture and perhaps even start fresh, not re-modify the original plans (make it a Revolution, not just an evolution). Part of my move (escape to) here was just for that reason, to start with a fresh station based on simplicity of operation (which takes a LOT of planning and work to obtain; in a couple years, it'll be there, I hope.)

GL,
Rick NK7I

On 3/13/2020 11:19 AM, Lyn Norstad wrote:

> Duane -
>
>
>
> I am of the mind that the antenna is the most crucial part of any
> station, and probably the most often maligned. I have made a number
> of presentations to ham groups on the design and construction process
> involved in getting the most bang for the buck, depending on your
> wants and needs (everybody's are different).
>
>
>
> In my own situation (2 acre semi-rural lot approx.150 feet x 600 feet
> running E-W feet, and active HOA) the goal was to have a single
> antenna that would provide the best primary signal on 80 meters in a
> North-South direction, while providing the best possible signal on 40
> meters in an East-West direction, consistent with the 80 meter
> performance and without unduly provoking the HOA (or my XYL).
>
>
>
> I decided on an Extended Double Zepp, cut for 3.5 MHz. That resulted
> in a length of 360 feet, which worked nicely since I have 400 feet
> clear from the house (West end) to a perfect tree for the far East
> end. And another tree in the center for support of both the antenna and the feedline.
>
>
>
> I am feeding it with a 160 foot length of 600 ohm "true ladder line."
> I can go into more detail if this sounds like something that would
> work. Modeling this antenna with EZ NEC shows a maximum theoretical
> gain of 4.7 dbi in both North and South directions. With the ladder
> line, a dual hybrid balun and short length of coax into the shack, my
> KAT500 tunes it very nicely on all bands 160 m thru 6m.
>
>
>
> I don't have your call so can't see where you are, but would be happy
> to make other suggestions based on the coverage you seek.
>
>
>
> 73
>
> Lyn, W0LEN
>
>
>
>
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]]
> Sent: Friday, March 13, 2020 11:52 AM
> To: Lyn Norstad; [hidden email]
> Subject: Re: [Elecraft] Off-Topic: Your advice/suggestion about
> antenna
>
>
>
> Hi Lyn - thanks for the reply!
>
> I have 3 acres of wooded land.
>
> Its pretty much on two different levels.
>
> The house is located on the lower level.
>
> And from there the grade goes upwards about 30 feet- and then levels
> off to the second level.
>
>
>
> Many elm trees which can support an antenna height of about 45 feet.
>
> And I can cut through a path through them if necessary.
>
>
>
> I have a 40m moxon pointed towards Asia at 45 feet hanging over solid
> rock
>
> I've made a few DX contacts with it during the years when propagation
> was peaking.
>
> But right now I think its really to low to the ground to be useful.
>
>
>
> I'm interested in what you have in mind.
>
> Thanks
>
> Duane
>
>
>
> On Fri, Mar 13, 2020, at 12:31 PM, Lyn Norstad wrote:
>
>> Duane -
>> There are other wire antenna options that will far outperform a
>> simple dipole, or for that matter a 2EL yagi.
>> How much space do you have available?
>> 73
>> Lyn, W0LEN
>> -----Original Message-----
>> From: [hidden email]
>> [mailto:[hidden email]] On Behalf Of
>> [hidden email]
>> Sent: Friday, March 13, 2020 10:38 AM
>> To: [hidden email]
>> Subject: [Elecraft] Off-Topic: Your advice/suggestion about antenna
>> From what I understand - solid rock below a raised vertical is not
>> the
> best
>
>> option for performance.
>> With an underlying geography of many feet of solid metamorphic rock -
>> that would probably rule out the low angle benefits of vertical antennas.
>> Consequently, over the years, every 40m vertical I've ever put up has
>> been out-performed by a dipole at .41 wavelength. I've also tried
>> the DX-Half Square and vertical Delta Loop with the same results.
>> It looks to me like my only option to outperform a 40m dipole - is a
>> tower and (at minimum) a 2EL yagi.
>> Would that assumption be correct?
>> Thanks
>> Duane
>> ______________________________________________________________
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john@kk9a.com

Re: Off-Topic: Your advice/suggestion about antenna

In reply to this post by dw-4

There is a lot of antenna misinformation on this list. Your initial
assumption is basically correct. A vertical does not have low angle
radiation unless you have a perfect ground, it will then low
pseudo-brewster angle which is very effective. A 1/2wl or higher 40m
dipole is actually a very good antenna and 2el shorty 40 or even
rotatable dipole is even better. A simple antenna model will show the
gain and pattern for all of these options.

GL
John KK9A

Duane wrote:

From what I understand - solid rock below a raised vertical is not
the best option for performance.
With an underlying geography of many feet of solid metamorphic rock -
that would probably rule out the low angle benefits of vertical
antennas.

Consequently, over the years, every 40m vertical I've ever put up has
been out-performed by a dipole at .41 wavelength. I've also tried the
DX-Half Square and vertical Delta Loop with the same results.

It looks to me like my only option to outperform a 40m dipole - is a
tower and (at minimum) a 2EL yagi.

Would that assumption be correct?
Thanks
Duane

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