One point 500/MHz =1/2 wavelength
I would hate for someone to think that is all the wire they need to use for a
delta loop.
Using the 1/4 wave 75 ohm transmission line is vital.
73 Don KO7I
Sent from my iPad
> On Nov 22, 2014, at 11:09 PM, Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de> wrote:
>
> 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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