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Re: Antenna question

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Richard-3

Re: Antenna question

Does that "middle of the country" include Chicago?

Rich
NU6T

On 2/13/2014 5:33 AM, James Rodenkirch wrote:

>
>
> "And QST recently published a piece showing that a better use of a 43 ft vertical might be as the center support for horizontal dipoles for 80 and 40, a concept with which I strongly agree." (smiley face annotation removed)
> As stated by a frtend of mine, after eading the above little ditty and replying, initially, "Snort," my friends goes on to add...."obviously, the author of that uninformed statement hasn't had to work stations on 80 and 40 from the middle of the country when signal arrival angles start changing dramatically and rapidly." (smiley face annotation re-inserted)
> 72/u3, Jim Rodenkirch K9JWV
>
>
>
>> Date: Tue, 11 Feb 2014 23:09:23 -0800
>> From: [hidden email]
>> To: [hidden email]
>> Subject: Re: [Elecraft] Antenna question
>>
>> On 2/11/2014 3:36 PM, George Thornton wrote:
>>> I have a small lot. I currently am using a 3 element Yagi that barely fits on the property. I was thinking about getting a vertical as a second HF antenna.
>> As it happens, over the past year or so I've been engaged in a serious
>> modeling study that compares the performance of vertical and horizontal
>> antennas at mounting heights that are practical for hams in your
>> situation. So the real question is, what will that vertical add to your
>> station beside a second antenna for SO2R?
>>
>> If I were in your situation, I would add an antenna only to cover bands
>> that the tri-bander does not. Even the best vertical is unlikely to
>> outperform the tribander unless you happen to be blessed with REALLY
>> good ground conductivity, and even then only by a dB or so at low
>> elevation angles. Second, if I were to add a vertical, it would be one
>> that is configured as a center-fed dipole, and I would add it ONLY if I
>> could elevate it at least 20 ft.
>>
>> Yes, I know this wasn't the question you asked, but it needs to be asked
>> and answered. :) Also, by all means pay attention to K6DGW's comments,
>> with which I completely concur.
>>
>> There's a link to a presentation I did last fall of the vertical height
>> issue, and also one about the recently popular 43 ft vertical.
>> http://k9yc.com/publish.htm
>>
>> I'm still working on the comparison of verticals to horizontal antennas
>> -- I've done all the modeling and know the results, but haven't
>> organized it to show yet. AD5X has also done some excellent work on the
>> 43 ft vertical idea. And QST recently published a piece showing that a
>> better use of a 43 ft vertical might be as the center support for
>> horizontal dipoles for 80 and 40, a concept with which I strongly agree. :)
>>
>> 73, Jim K9YC
>>
>>
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>
>
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Wes (N7WS)

Re: Antenna question

In reply to this post by Jim Brown-10

Well, I was speaking of my situation.

I'm in the Sonoran Desert of southern AZ with ground that varies from granite to
sand to caliche within a few feet distance.

Although many (most?) hams consider vertical antennas to be "low-angle"
radiators, they often fail to consider the efficiency of that "low-angle"
radiator. My modeling shows that even a low lambda dipole with its "high-angle"
radiation often has more signal radiated at the vertical's optimum (low) angle
than the vertical does. Plotting the two antennas and overlaying the plots will
easily show this.

Now I'm not going to argue with the guys with heroic vertical phased array
installations and the like, but for the typical guy contemplating a modest
vertical installation v. a straightforward dipole or "inverted-vee" I would (and
did) choose the dipole. Besides, I think that low angle is often overrated.

Although I'm normally loath to state anecdotal evidence, my paralleled wires 40
and 80-meter inverted-vee with apex at 40 ft and ends at 20 feet models as a
NVIS antenna, but I have 148 DXCC countries (including antipodal FT5ZM) worked
on 80-meters and I don't much care for 80-meters so seldom operate there.

Wes N7WS

On 2/12/2014 4:17 PM, Jim Brown wrote:

> On 2/12/2014 7:29 AM, Wes (N7WS) wrote:
>> Also known as, "The worst horizontal antenna is better than the best vertical
>> antenna" theory. It's always worked out for me. Now if I lived on the beach...
>
> Hi Wes,
>
> Based on my model studies, I wouldn't go that far -- it depends on how high
> either of the antennas are, as well as the quality of the ground. If your
> criteria is low angle radiation and you have better than average soil, a
> vertical dipole that's 20 ft or more above ground will beat a low dipole. Here
> in the mountains, our soil is stinko, so the only band where a vertical beats
> a horizontal dipole is 160M.
>
> 73, Jim K9YC

Jim Brown-10

Re: Antenna question

On 2/13/2014 1:04 PM, Wes (N7WS) wrote:
> Well, I was speaking of my situation.
>
> I'm in the Sonoran Desert of southern AZ with ground that varies from
> granite to sand to caliche within a few feet distance.

My modeling studies, as well as my results with soil that's nearly as
bad, are in complete agreement with your analysis.

73, Jim K9YC

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Don Wilhelm-4

Re: Antenna question

In reply to this post by Wes (N7WS)

Wes and all,

From my practical experience, your modeling analysis is correct.
I have a vertical for 80 and 40 with elevated radials (full size except
for the loading of the 40 meter trap) - in A/B tests compared with my 80
and 40 meter dipoles with the center at 45 feet and ends at 20 feet or
greater, I have found that copy on *all* stations is better using the
dipoles than with the vertical.

The only reason the vertical stays up is because it also functions as a
160 meter inverted L which is my only 160 meter antenna at the present time.

73,
Don W3FPR

On 2/13/2014 4:04 PM, Wes (N7WS) wrote:

> Well, I was speaking of my situation.
>
> I'm in the Sonoran Desert of southern AZ with ground that varies from
> granite to sand to caliche within a few feet distance.
>
> Although many (most?) hams consider vertical antennas to be
> "low-angle" radiators, they often fail to consider the efficiency of
> that "low-angle" radiator. My modeling shows that even a low lambda
> dipole with its "high-angle" radiation often has more signal radiated
> at the vertical's optimum (low) angle than the vertical does.
> Plotting the two antennas and overlaying the plots will easily show this.
>
> Now I'm not going to argue with the guys with heroic vertical phased
> array installations and the like, but for the typical guy
> contemplating a modest vertical installation v. a straightforward
> dipole or "inverted-vee" I would (and did) choose the dipole. Besides,
> I think that low angle is often overrated.
>
> Although I'm normally loath to state anecdotal evidence, my
> paralleled wires 40 and 80-meter inverted-vee with apex at 40 ft and
> ends at 20 feet models as a NVIS antenna, but I have 148 DXCC
> countries (including antipodal FT5ZM) worked on 80-meters and I don't
> much care for 80-meters so seldom operate there.
>

daleputnam

Re: Antenna question

In reply to this post by Jim Brown-10

My modeling experience pretty much says the same... for higher angle arrivals... the dipoles under 1/2 or more, will be better... especially when placed within one hop of the ocean. (East or West.....).. HOWEVER... taking one hop off... (that's the same almost) as gaining 2 - 3 S unites... is better.. and taking one hop off with a dipole... at less thanoptimum height is nigh on impossible. With an optimum vertical.. or LOW angle antenna...it IS possible. This is all derived with modeling.. AND.... Since I don't believe computers have ever actually DONE IT... I kinda like to prove it empirically. And I have... the last time was with FT5ZM... with a very LOW angle antenna... they were attained on4 bands.... the dipole didn't work. The dipole at near optimum height was 3 S units lower in rx... on a calibratedS meter.... THAT particular day.... and it was 1 - 3 S units less for over a week that I listened... HOWEVER.. there werea few times.. especially when the band was ful
l of QSB..shifting and changing... that the dipole did hear better... and significantly... for short periods of time. I, being one, and only me... prefer to hear for a much longer period of time... more reliably... rather than count on a few short bursts of signal, ... every cycle of the band.... (about 2 times a day.... ) I can't count on being at the radio at the optimum time... but I can count on being at the radio.... when I want to!
Have a great day,

--... ...--
Dale - WC7S in Wy

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Stephen Selberg

Re: Antenna question

I'm not by any means an antenna expert. All I can say is with ft5zm, they
were much stronger on the vertical than my dipole on 20 meters. Some how
some way, I was able to work them on 40 cw with the hustler vertical.

The conclusion I've come to is there's times where my dipole works better
for DX and there's times the vertical works better. Guess that's why I
still have them both up. But that's what makes Amateur Radio so fun, seeing
what works and what doesn't, and how one might be great one day, but not so
good the next. I love radio...

Enjoy experimenting...

73 Steve KS6PD

Sent from my iPhone. Forgive the typos.

On Thursday, February 13, 2014, Dale Putnam <[hidden email]> wrote:

> My modeling experience pretty much says the same... for higher angle
> arrivals... the dipoles under 1/2 or more, will be better... especially
> when placed within one hop of the ocean. (East or West.....).. HOWEVER...
> taking one hop off... (that's the same almost) as gaining 2 - 3 S unites...
> is better.. and taking one hop off with a dipole... at less thanoptimum
> height is nigh on impossible. With an optimum vertical.. or LOW angle
> antenna...it IS possible. This is all derived with modeling.. AND....
> Since I don't believe computers have ever actually DONE IT... I kinda like
> to prove it empirically. And I have... the last time was with FT5ZM...
> with a very LOW angle antenna... they were attained on4 bands.... the
> dipole didn't work. The dipole at near optimum height was 3 S units lower
> in rx... on a calibratedS meter.... THAT particular day.... and it was 1 -
> 3 S units less for over a week that I listened... HOWEVER.. there werea few
> times.. especially when the band was ful
> l of QSB..shifting and changing... that the dipole did hear better... and
> significantly... for short periods of time. I, being one, and only me...
> prefer to hear for a much longer period of time... more reliably... rather
> than count on a few short bursts of signal, ... every cycle of the band....
> (about 2 times a day.... ) I can't count on being at the radio at the
> optimum time... but I can count on being at the radio.... when I want to!
> Have a great day,
>
>
> --... ...--
> Dale - WC7S in Wy
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
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Wes (N7WS)

Re: Antenna question

In reply to this post by Wes (N7WS)

Quoting myself:
> Besides, I think that low angle is often overrated.

Here's some supporting evidence: (for ARRL members)

http://www.nxtbook.com/nxtbooks/arrl/qst_201203/index.php#/42

Wes N7WS
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Re: Antenna question

In reply to this post by Richard-3

It depends on which side of Chicago you are talking. NW of Chicago there is a big lode of iron which makes verticals work very well with few radials as they do here on the Gulf Coast for DX. A 43 ft vertical is 5/8 wave on 20 meters which will give it about 3 db gain over a 1/4 wave vertical with equal counterpoise. Both will do better than a horizontal dipole at average heights and are easier to erect than a dipole at 50 to 100 feet. Low dipoles will usually do better at distances less than 1000 miles and well counterpoised verticals at distances more than 2000 miles. Conductive grounds will allow you to get away with fewer radials, but if you live in the desert the counterpoise will be difficult. It depends is a phrase that rings true with antennas more than other things. Read the ARRL Antenna Handbook from cover to cover then read it again. Repeat at 1 or 2 year intervals and buy a new copy every few years. Understanding antennas is
difficult for Physicists and Electrical Engineers (I am both) and even more difficult for others, so plan on putting in the study, modeling time, construction time and enjoy. It is arguably the most difficult and enjoyable part of ham radio.

Willis 'Cookie' Cooke, TDXS DX Chairman
K5EWJ & Trustee N5BPS, USS Cavalla, USS Stewart

________________________________
From: Rich <[hidden email]>
To: [hidden email]
Sent: Thursday, February 13, 2014 9:07 AM
Subject: Re: [Elecraft] Antenna question

Does that "middle of the country" include Chicago?

Rich
NU6T

On 2/13/2014 5:33 AM, James Rodenkirch wrote:

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______________________________________________________________
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