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Blind-Hams For blind ham radio operators <[log in to unmask]>
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From:
John Miller <[log in to unmask]>
Date:
Wed, 28 Dec 2005 23:42:21 -0500
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Blind-Hams For blind ham radio operators <[log in to unmask]>
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I know a guy who experiments with antennas all the time and he says the
delta loop he uses on 20 the last few years before he was unfortunately
forced off the air for the most part, was the best antenna he ever ran. I
guess he's still on digital modes now but he's not in to those modes much.
----- Original Message -----
From: "Colin McDonald" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, December 28, 2005 11:34 PM
Subject: Re: antenna building


that logic only applies to ground wave type communications.
The horrizontal and vertical polarizations alter greatly as they travel long
distances, to the extent that generally speaking, the polarization plays a
signifigantly lesser roll in dx communications then it does in ground wave
or sky wave communications like on 160, 80 and 40 meters.
Verticals for HF generally do not have any gain because they are typically a
quarter wave length...this due to the long wave length and the fact that
most people cant have anything more then a 60 foot vertical antenna for 80
meters.
Gain on HF can usually only be had by using a beam, or a loop type antenna.

One of the antennas i have been wanting to try is a 20 meter delta
loop...fairly small and easy to build and apparently with great
characteristics

73
Colin, V A6BKX
----- Original Message -----
From: "Frederick" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, December 28, 2005 8:00 PM
Subject: Re: antenna building


> I have heard much debate about verticals having low gain.  It would seem
to
> me that the biggest loss is do to a vertical that is being received by a
> horizontal and vice versa.
> Mark WZ0K
> God loves you!
> My personal prayer book.
> Add your prayer or pray for others at the following link.
> http://path-to.net/fhrp
> http://lists.topica.com/lists/funhamradio.
>
> http://path-to.net/fhr
> ----- Original Message -----
> From: "Colin McDonald" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, December 28, 2005 5:44 PM
> Subject: Re: antenna building
>
>
> >I would imagine that the helically wound antenna would be much like a
> > quarter wave yes, something around a 25 degree angle of radiation.
> > Not terribly great for dx on 20, but not bad for north America wide or
> > even
> > the closer in ground wave stuff.
> > Perhaps a better pursuit would be to try for a 40M antenna helically
> > wound.
> > Of course one would have to use a bigger sized pvc pipe to get better
> > results and band width.
> > I wonder if loaded radials would be a compromise or not?
> > For effective radials on a 40M vertically, one would have to have at
least
> > four 30 foot long wires...if one wound a coil of about 20 feet and then
> > had
> > a 10 foot peace of straight wire going out from the base of the vertical
> > peace, I wonder if this would work as well as a straight run of 30 feet.
> > I suppose the whole point of a counter poise is to try and make
something
> > that the wave can reflect off of, and that would have to be a quarter
wave
> > long, not partially coils...the effective length has to be divisables or
> > multiples of that radiated wave length I would think.
> > 73
> > Colin, V A6BKX
> >
>

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