If I were to put a Beverage above one of my barbed wire fences, I would put
it at 10 feet to, hopefully, minimize the effect of the fence on the
Beverage.
Chuck W5PR
On Tue, Feb 3, 2015 at 7:39 AM, Patrick Greenlee <patrick_g@windstream.net>
wrote:
> Chuck, A very good point.
>
> That is the essence of my interest in the effect of having some parallel
> grounded conductors (5 strand barbed wire fence with steel posts) a short
> (TBD) distance below the beverage antenna. I'm curious to know if the fence
> would act similar to good conductivity dirt WRT Beverage performance.
>
> If not, then what if the antenna wire were mounted above 3 parallel but
> horizontally spaced conductors looking for the beginnings of the effect
> that would be achieved theoretically with our old friend the infinite
> conductive plane over which we mount our verticals? Why 3? Because it
> would be easy to put a strand of wire on either side of the top strand of
> barbed wire using readily available inexpensive plastic insulating arms
> made expressly for adding electric fence wire to a fence built with
> T-posts. With a little more fussing I could attach 2 wires either side of
> the center wire giving a better approximation of the infinite plane. One
> of our experts can maybe tell me if the parallel grounded wires need to be
> tied together laterally or if that would matter.
>
> Patrick NJ5G
>
>
>
> On 2/3/2015 7:00 AM, Chuck Dietz wrote:
>
>> Part of the problem with comparisons of low band receiving antennas made
>> in
>> various locations is that the composition of the ground under the antenna
>> makes a huge difference.
>>
>> Chuck W5PR
>>
>> On Mon, Feb 2, 2015 at 8:22 PM, Roger (K8RI) on TT <
>> K8RI-on-TowerTalk@tm.net
>>
>>> wrote:
>>> That's why I have the HB and Antenna HB on the same machine as the mail.
>>> Items, topics, and components are so much easier and faster to find than
>>> with hard print. Less than 10 keystrokes to find nearly any specifics
>>> on a
>>> topic. Course as some of my answers have shown, I'm too lazy to always
>>> double check!
>>>
>>> I can't say the computer is smaller, lighter, or cheaper at 60#, 23"H X
>>> 7.5"W X 20" D, running 8 64 bit cores/CPUs @ 4.1 GHz, & 16 GB of RAM
>>> and
>>> cost less than half our first color TV. OTOH the Internet has been a POS
>>> this past week, so I'm glad I had most of the data here. Still, with
>>> posted links on mans news groups, they came up invalid (err 404) even
>>> from
>>> news sites and some ham pages were taking so long to load they timed out.
>>> I don't think I was getting more than a fraction of the 100 Mbs service I
>>> pay for.
>>>
>>> Speaking of "pay for" and I think this is relevant to hams who depend on
>>> electricity... My electric use in the shop has been down this past year
>>> and
>>> on the equalized billing plan It almost doubled last month (with less
>>> use)
>>> I think I smell a rate increase a coming.
>>>
>>> 73
>>>
>>> Roger (K8RI)
>>>
>>>
>>>
>>> On 2/2/2015 2:14 PM, Jim Brown wrote:
>>>
>>> On Mon,2/2/2015 10:05 AM, Don wrote:
>>>>
>>>> First, I'm surprised there does not seem to be any published
>>>>> measurements taken at a common test site of a Beverage at various
>>>>> heights
>>>>> and lengths (such as done with yagi's, and other antennas on test
>>>>> ranges).
>>>>>
>>>>> Why do you assume that nothing like this exists? Beverages have been
>>>> around for nearly a century, and it is quite likely that there's a lot
>>>> of
>>>> published work that you haven't looked for in scientific journals. It's
>>>> also possible to model antennas like this and do your own study.
>>>> There's a
>>>> lot about Beverages (and other RX antennas) in the ON4UN book, and in
>>>> the
>>>> ARRL Antenna Book.
>>>>
>>>> Email reflectors like this one should not be a substitute for pulling
>>>> out
>>>> the books and studying them. Many of us who post answers to questions
>>>> like
>>>> this have done that study, or done that modeling, or built those
>>>> antennas,
>>>> and are sharing what we've learned. As VE7RF has noted, optimum height
>>>> is a
>>>> function of wavelength. When a Beverage is higher than that, it doesn't
>>>> stop working, like throwing a switch, it just becomes less effective. My
>>>> 550 ft Beverages, a full wavelength on 160M, at an average height of 5-6
>>>> ft, are quite effective on 40M, and are still working on 20M! How do I
>>>> know? I run diversity with my K3 using the TX dipole at 125 ft into the
>>>> main RX and the Beverage into the second RX.
>>>>
>>>> 73, Jim K9YC
>>>> _______________________________________________
>>>>
>>>>
>>>>
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>>>> TowerTalk@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>
>>>>
>>> --
>>>
>>> 73
>>>
>>> Roger (K8RI)
>>>
>>>
>>> ---
>>> This email has been checked for viruses by Avast antivirus software.
>>> http://www.avast.com
>>>
>>>
>>>
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>>>
>>>
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>>
>>
>>
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