Reed, a 17m vertical delta loop (no a lazy loop) is what I'm talking about,
and you need only about 20 ft. of width for it. It takes up less space than
a dipole. The point is at the top of the single pole and the horizontal
wire is at the bottom. The feedpoint is 1/4 wavelength down either leg from
the point. Use a quarter wavelength matching stub of RG-59 or RG-11. The
50 Ohms the rest of the way.
Here is a picture of my 40m vertical delta loop:
http://www.dj0ip.de/my-favorite-antennas/my-favorite-40m/
Just scale it down to size for 17m.
The exact length of the sides and horizontal wire are not critical, but the
sides must be at least 1/4 wavelength long.
You'll maybe notice that the quarter wavelength of wire above the feedpoint
on my 40m loop looks just a little long.
It is longer than a calculated quarter wavelength if when using a dipole
formula (468/f). That's because there is no "End Effect" present in a loop.
Use 500 instead of 468 (or "250" for a quarter wavelength) when calculating
where to place the feedpoint.
73 - Rick, DJ0IP
(Nr. Frankfurt am Main)
-----Original Message-----
From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Reed
Sent: Sunday, November 23, 2014 12:05 AM
To: tentec@contesting.com
Subject: [TenTec] 17 Meter Antenna
Yeah Rick I have heard good things about the delta loop. I don't know if I
have the real estate for one, but will look into it. I have 2 portable
magnetic loop antennas that work really well for their size, but they are
not designed for wet WX. Low noise is one great advantage of any loop
antenna.
Thanks!
Reed W4JZ
>Reed, try a full wave delta loop,
>Horizontal segment on the bottom
>Fed in one corner with 1/4 wavelength of 75 Ohm coax, then fed to the
>shack with 50 Ohm coax.
>You'll knock em dead with that!
>73 - Rick, DJ0IP
>(Nr. Frankfurt am Main)
>Thinking about building a Moxon. Easy to build &
>inexpensive. Anyone here used one before?
>73,
>Reed W4JZ
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