To: <towertalk@contesting.com>
>Date: Sat, 09 Aug 1997 18:55:15
>To: CQK8DO@aol.com
>From: Jan & Del Seay <seay@alaska.net>
>Subject: Re: [TowerTalk] Gap Vertical, Verticals in general
>
>
>DennY: What happens in a ground plane radiator is that it's major lobe
>starts to come down. You're not upping the gain, per se, but putting the
>major lobe closer to the horizon where it does some good. This continues
>up to about 5/8 wavelength, and then starts to break out with some minor
>lobes at higher angles. Then, after about 1 wavelength, it tends to end-fire
>which is great for space communications!
>Max gain at the horizon for a gp is considered to be 5/8 wavelength.
>Hope this helps. de KL7HF
>
>
>At 08:49 AM 8/9/97 -0400, you wrote:
>>I have not seen the aforementioned article... But, the broadcast industry
>>did extensive experiments in the early days, as did Sevick, and a number of
>>others in more recent years, including Al's excellent article in the most
>>recent Antenna Compendium #5, and this information is readily available... In
>>spite of this body of literature there seems to be some mystical quality
>>attributed to radials, which mystifies me...
>>Consider, that a groundplane antenna is a 1/4 wave radiator over a set of
>>radials, which is nothing more, or less, than a vertical dipole which has had
>>the lower leg split lengthwise and spread out radially, and then the whole
>>antenna has been lowered to ground proximity (to it's detriment)... Other
>>than modifying ground losses immediately under the antenna, which is well
>>understood and well quantified in the literature, I cannot fathom how
>>changing the length of one side of a dipole is going to magically alter the
>>gain...
>>
>>Denny
>>
>><I believe the next significant improvement in verticals will come
>>from extensive investigations into the lengths of the radials, as
>>an article from Communications Quarterly stated earlier.>
>>
>>
>>--
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>>
>
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