Thanks all for the on and off list responses. The reminder re the current and
voltage min and max points in the circular elements was helpful.
73
Mark S
VE7AFZ
Sent from my iPhone
> On Oct 3, 2016, at 12:24 PM, Bill Olson <callbill@hotmail.com> wrote:
>
> yeah, like a "cubical quad", which is a full wave loop element .. what makes
> it different from the HF quad you normally think of is that all the low
> impedance points are all tied together to ground (the boom)..
>
>
> you could also think of it as a big fat folded dipole..
>
>
> back in the original Down East Microwave days I *had* experimented with
> floating the elements and feeding it in both planes out of phase to actually
> get circular polarization, but the whole thing got pretty messy and I gave up
> on that.. There WAS some interest for satellite work..
>
>
> Anyway with the manufactured antennas you get these days, with the semi-rigid
> feedline that goes through the driven element vertical the polarization is
> horizontal and vice versa.. always linear though..
>
>
> bill
>
>
> ________________________________
> From: VHFcontesting <vhfcontesting-bounces@contesting.com> on behalf of Zack
> Widup <w9sz.zack@gmail.com>
> Sent: Monday, October 3, 2016 6:12 PM
> To: VHF Contesting Reflector
> Subject: Re: [VHFcontesting] Loop Yagi theory
>
> It's basically the same idea as with a quad antenna. A loop (either
> circular or square) fed at the bottom or top has current peaks at the
> feedpoint and opposite side of the quad or loop, and voltage peaks at the
> side points (90 degrees to the feedpoint). This is similar to a horizontal
> dipole antenna, which has horizontal polarization.
>
> There's more to it than that, but that's the basic idea.
>
> 73, Zack W9SZ
>
>
> On Mon, Oct 3, 2016 at 12:38 PM, Mark Spencer <mark@alignedsolutions.com>
> wrote:
>
>> Hi does anyone know of a web site that explains why loop yagis are
>> horizontally or vertically linearly polarized ?
>>
>> I recently gave a presentation to a local club on VHF and up weak signal
>> operating and when I showed pictures of one of my 1296 loop yagi antennas I
>
> yeah, like a "cubical quad", which is a full wave loop element .. what makes
> it different from the HF quad you normally think of is that all the low
> impedance points are all tied together to ground (the boom)..
>
>
> you could also think of it as a big fat folded dipole..
>
>
> back in the original Down East Microwave days I *had* experimented with
> floating the elements and feeding it in both planes out of phase to actually
> get circular polarization, but the whole thing got pretty messy and I gave up
> on that.. There WAS some interest for satellite work..
>
>
> Anyway with the manufactured antennas you get these days, with the semi-rigid
> feedline that goes through the driven element vertical the polarization is
> horizontal and vice versa.. always linear though..
>
>
> bill
>
>
> ________________________________
> From: VHFcontesting <vhfcontesting-bounces@contesting.com> on behalf of Zack
> Widup <w9sz.zack@gmail.com>
> Sent: Monday, October 3, 2016 6:12 PM
> To: VHF Contesting Reflector
> Subject: Re: [VHFcontesting] Loop Yagi theory
>
> It's basically the same idea as with a quad antenna. A loop (either
> circular or square) fed at the bottom or top has current peaks at the
> feedpoint and opposite side of the quad or loop, and voltage peaks at the
> side points (90 degrees to the feedpoint). This is similar to a horizontal
> dipole antenna, which has horizontal polarization.
>
> There's more to it than that, but that's the basic idea.
>
> 73, Zack W9SZ
>
>
> On Mon, Oct 3, 2016 at 12:38 PM, Mark Spencer <mark@alignedsolutions.com>
> wrote:
>
>> Hi does anyone know of a web site that explains why loop yagis are
>> horizontally or vertically linearly polarized ?
>>
>> I recently gave a presentation to a local club on VHF and up weak signal
>> operating and when I showed pictures of one of my 1296 loop yagi antennas I
>> was asked if they were circularly polarized. I don't think my answer that
>> they were sold to me by the manufacturer as being horizontally polarized
>> and other local hams use similar horizontally antennas, and as a result I'm
>> able to make contacts with them was quite what the audience was hoping for
>> (although from the perspective of getting on the air and making contacts I
>> believe it was a reasonable answer.)
>>
>> The next time I give a similar presentation it would be nice to point
>> people to a web site that explains this in detail (:
>>
>> Thanks in advance for any suggestions. (Some google searching didn't
>> turn anything up and reading thru the loop yagi section in my arrl antenna
>> books also didn't give me an answer.)
>>
>> 73
>>
>> Mark S
>> VE7AFZ
>> _______________________________________________
>> VHFcontesting mailing list
>> VHFcontesting@contesting.com
>> http://lists.contesting.com/mailman/listinfo/vhfcontesting
>
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> lists.contesting.com
> The VHF Contesting Reflector is designed to be a place to discuss all aspects
> of contesting on frequencies of 50 MHz and above. We hope to generate
> discussions of any ...
>
>
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