Mike and Gang,
It was this project (terminated bowtie) that got me looking into the KD9SV
994 x5 preamp a few months ago (I published some info on this preamp a few
months ago). I think the KD9SV 994 x5 preamp sometimes called the KD9SV
VLN preamp (very low noise preamp) would be perfect for use with this type
antenna.
Just FYI,
Don (wd8dsb)
On Sun, Dec 11, 2016 at 10:12 AM, Don Kirk <wd8dsb@gmail.com> wrote:
> Hi Mike,
>
> Funny you should ask that.
>
> A few months ago (September) I was looking at building a smaller size DHDL
> using 4Nec2, and there were a few things I saw that I thought needed
> improvement (I saw things in the full size DHDL that I thought needed
> improvement, it was not limited to the small size DHDL I was trying to
> design). Then I started to play around with the location of its
> termination resistor as well as routing of wires, and wound up with what I
> called the Terminated Bowtie. I built one in my backyard but my yard is
> pretty small and the antenna was too close to existing objects (house and
> chain link fence) and I did not realize the S/N improvement that I
> expected, nevertheless based on modeling it looks like a winner (9.5 RDF
> and front to back ratio versus elevation angle very robust).
>
> I have attached the preliminary document I put together a few months ago
> for you and others to view (it might not be perfect, but should convey my
> design / thoughts). I would love someone to build one of these out in the
> open to see if the real life build provides results similar to the 4Nec2
> modelling I did.
>
> Note: Bringing the feedline away from the antenna properly needs to be
> looked at to minimize distortion of the pattern. As I recall the feedline
> should not drop down to the ground until it's at least 5 feet away from the
> antenna, and a greater distance would be best. The feedline should also
> use choke with ground rod similar to what's recommend for other RX antennas
> we use (beverages, flags, etc.) to block common mode noise from making its
> way to the antenna feedpoint.
>
> Let me know what you think. It might not work, but sure looked good on
> paper.
>
> 73,
> Don (wd8dsb)
>
> On Sun, Dec 11, 2016 at 9:41 AM, D Michael <damichael@verizon.net> wrote:
>
>>
>>
>> I have two flag rx ants and I was looking at the DHDL and DK6ED Double
>> Loop System V2 and wondering if twisting my Flag rx ants into Bowties
>> would improve the forward pattern and make them narrower with better front
>> to back.
>> I would just ""flip"" the termination resistor end to form a loose BOWTIE
>> shape.
>> I have no ant modeling software so I have no way to ponder this change.
>> Maybe someone could model doing this.
>> TNX es 73, Mike W3TS
>> _________________
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>>
>
>
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