[TowerTalk] BIG WIRE BEAMS FOR 75 METERS

[Joe Subich, W4TV]

 > 3.  Yagi's need to be a half wave high to really play,
 > but they may still hear OK at a lower height.

The crossover point between a dipole and vertical is actually
about 0.4 wavelength.  A Yagi will have a slight advantage over
a dipole because of the slightly reduced (ca. 3 dB) radiation
up/down.

 > 4.  Verticals with a good ground system are as good
 > as Yagi's for transmit depending on your ground conductivity.
 > Fortuitously, I have very high ground conductivity, but
 > of course YMMV.

Verticals suffer an automatic 6 dB penalty because of the lack
of ground gain.  Yes, a vertical does very well in the ground-
wave region - better than any high dipole/yagi.  However, once
the dipole/yagi is above 0.4/0.35 wave (100 feet/30 meters) the
horizontal antenna has better radiation at all take-off angles
in its "forward" direction than the vertical (vs. dipole) or
4 square/vertical beam (vs. yagi).

73,

    ... Joe, W4TV


On 7/16/2013 11:48 AM, Richard (Rick) Karlquist wrote:
> The general consensus of the big guns on 75 meter
> long path (mainly west coast to EU) was:
>
> 1.  Yagi's hear better than verticals
>
> 2.  On receive, having low sidelobes is more important
> than forward gain or RDF or beam width, especially if
> your noise is not uniform.  For example, my quietest direction,
> fortuitously, is 210 degrees, the direction of long path to Europe.
> Rejection of noise from other directions makes all the
> difference.  A 4 square adjusted for a really clean
> pattern may hear better than 7 elements with sidelobes.
> Also, the 4 square should NOT be wide spaced.
>
> 3.  Yagi's need to be a half wave high to really play,
> but they may still hear OK at a lower height.
>
> 4.  Verticals with a good ground system are as good
> as Yagi's for transmit depending on your ground conductivity.
> Fortuitously, I have very high ground conductivity, but
> of course YMMV.
>
> If you go with verticals, you generally need an alternate
> receive antenna strategy.
>
> Rick N6RK
>
> On 7/16/2013 8:26 AM, Jorge Diez - CX6VM wrote:
>> I you have the supports for a 7 elements wire beam, I think will work as
>> support for 7 wire verticals, right?
>>
>> Which is better, more gain? The 7 elements wire beam or 7 wire verticals
>> with the corresponding radials?
>>
>> Thanks!
>> Jorge
>> CX6VM/CW5W
>>
>> -----Mensaje original-----
>> De: TowerTalk [mailto:towertalk-bounces at contesting.com] En nombre de
>> Richard
>> (Rick) Karlquist
>> Enviado el: martes, 16 de julio de 2013 12:11
>> Para: floyd koontz
>> CC: towertalk at contesting.com
>> Asunto: Re: [TowerTalk] BIG WIRE BEAMS FOR 75 METERS
>>
>> One of the regulars on 3.795 MHz around west coast sunrise a few years
>> back
>> had a wire beam with something like 7 elements beaming the long path to
>> Europe.  He got great results with it.
>>
>> Rick N6RK
>>
>> On 7/16/2013 5:47 AM, floyd koontz wrote:
>>> Sergio all of my info on this subject is on my website  www.wa2wvl.com
>>>
>>> In New Youk I had a 7 element on a 100 meter boom 100 feet in the air
>> toward JA. It worked great.
>>>
>>> Floyd
>>>
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