Gents,
I would not feed only with vertical... That would make no sense to me. Feed
Both polarities with separate feedlines!!! Then you can choose either, or
both with phase shift if you want to play with circular. I have compared the
vertical and horizontal patterns independently on my quad and found that at
50 feet to the boom, they are very close. At less than 36 feet (<1
wavelength, no tests were done) I would think the horizontal polarization
would be more affected, since the elements are in the same plane as the
ground. BTW... Both have >30 dB front to back and a little more off the back
corners (4 elements) at 50ft with my design. Gain of the vertical feedpoint
on the quad over the antron99 is about 10/12dB. I had no dipole to compare
for the horizontal polarization gain comparison test.
George AB2KC
----- Original Message -----
From: "K4SAV" <RadioIR@charter.net>
To: <towertalk@contesting.com>
Sent: Sunday, January 08, 2006 9:10 PM
Subject: Re: [TowerTalk] 10 Meter Beams - Any IDEAS
> OK, I'll concede one point.
>
> If your interested in local ground wave contacts, then the fact that you
> lose most of the antenna gain with a vertically polarized quad, probably
> doesn't matter. But I don't think it's the kind of thing a contester
> would be interested in doing.
>
> Jerry, K4SAV
>
> K4SAV wrote:
>
>>I would not recommend feeding an HF quad with vertical polarization. If
>>you do that, the antenna pattern is no longer reinforced by ground
>>reflections, and you end up with something that has less than free space
>>gain. If you have a UHF antenna that is far enough above ground to not
>>care about ground reflections, then maybe it doesn't matter.
>>
>>Jerry, K4SAV
>>
>>George P. wrote:
>>
>>
>>
>>>Michael,
>>>Quads rule. 4 elements minimum and you'll be on top. Set driven element
>>>up
>>>for both vertical AND horizontal. Use same feedline length for each
>>>polarity, and you can play with circular polarization if you add 90
>>>degrees
>>>phase length (1/4W) in one of the feedlines. Vertical is great for late
>>>night ground wave for mobile contacts, state to state <200 miles and the
>>>local repeaters. You may e-mail me for more info on how to set it up.
>>>When
>>>the band dies... there's always guys on groundwave using A99 verticals.
>>>George AB2KC
>>>
>>>----- Original Message -----
>>>From: "Michael Mark" <m2eng@mts.net>
>>>To: <towertalk@contesting.com>
>>>Sent: Friday, January 06, 2006 8:32 PM
>>>Subject: [TowerTalk] 10 Meter Beams - Any IDEAS
>>>
>>>
>>>
>>>
>>>
>>>
>>>>I like contesting and have the Canadian 10M Phone LP SSB record which I
>>>>did
>>>>in 1991 with about 2500 QSO's.
>>>>
>>>>I used a Hy Gain LJ105 on a 48' tower back then at my old QTH.
>>>>
>>>>I have a couple of bucks now so I want something better for the upcoming
>>>>Sunspot Cycle increase.
>>>>
>>>>I have a 48' tower at my office building with nothing on it.
>>>>
>>>>As well, my flat building roof is 65' x 45' with 16' in height.
>>>>
>>>>I have new: A Stack Match for 2 antennas, new Ham IV and 2 Hy Gain
>>>>LJ105CA's and a Glen Martin 8' Roof tower.
>>>>
>>>>I was also considering a M2 10M7 or a Force 12 MAG 810 as well.
>>>>
>>>>Just asking for some ideas or experiences from you Contesters about your
>>>>10M antenna recommendations.
>>>>
>>>>Tnx
>>>>
>>>>Michael Mark, P.Eng., VE4MM
>>>>_______________________________________________
>>>>
>>>>
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>>>>
>>>>
>>>>
>>>>
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>>>
>>>
>>>
>>>
>>
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>
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