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Re: Topband: high take-off angle

To: Merv Schweigert <k9fd@flex.com>
Subject: Re: Topband: high take-off angle
From: k3bu@optimum.net
Reply-to: k3bu@optimum.net
Date: Mon, 17 Oct 2011 19:28:54 +0000 (GMT)
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Yea, there are high angle signals, anyone can verify that by having perhaps the 
simplest antenna - Inverted Vee at least some 30 ft up. Careful with 
interaction with other antennas within about 1 wavelength.
 
My old CQ article at http://www.k3bu.us/propagation.htm explores some of that.
 
The thing about L or T loading is that in both cases we radiate the same power, 
except the T loading cancels the radiation from both top of the T legs and 
vertical polarization and angles prevail.
The radiation pattern is affected both on RX and TX. On RX this can be used to 
reject high angle or horizontal polarization signals/noise using T loading.
If one desires some horizontal and high angle component than use just L.

I found very good performer in "sorta side U", where it has elevated radial 
about 1/8 wavelength, vertical radiator as high as practical, loading coil at 
the top and rest of the sloping wire to bring the system to resonance - for 
total of 3/8 electrical radiator. By moving the feedpoint it is easy to find 50 
ohm impedance, so no matching gizmos needed. Pattern is hardly skewed.
One radial probably helps horizontal/high angle.

So it is 1/8 radial(s) and 3/8 radiator with vertical/horizontal components. I 
used it from the Jersey shore beach house, close to the water. Easy to tune, 
works well, no introduced loses.
Something like K3BU-drunk U?

Yuri K3BU.us
www.MVmanor.com
Jersey shore beach house vacation rentals

> I agree that some high angle may be the optimum at some 
> situation, but getting all angles from one
> antenna I cant see as the answer, you are putting power into 
> all the different angle
> and no real power into any one of them. So separate antennas 
> would seem to
> be the answer. If your putting power into the higher angles of 
> an InvL you are not
> putting max power into the lower angles when needed.
> 
_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK

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