Mike, you suggested a delta loop. It is important that if Simon decides to
hang a delta loop between towers that you feed it a the corner rather than
at the bottom. This should give you some vertical component at a much
lower take-off angle rather than being a clod warmer on 80 meters.
Unfortunately, the towers supporting the delta loop will modify the pattern
a bit but if the broadside is in a favored direction it could actually help
you. Maybe someone could model this for you even though if would be a
complex assignment.
Herb Schoenbohm, KV4FZ
On Sat, Sep 15, 2018 at 1:11 AM Mike Furrey <mikefurrey@att.net> wrote:
> Hi Simon,I would like to suggest hanging a 1 wavelength delta loop off of
> the 50 meter tower. Easy to build, easy to match, about 1.5 db gain and you
> don't need to do all that work laying down radials, etc and trying to match
> an odd length tower. The loop will be almost omni directional and it will
> be bit more broad banded than a vertical, dipole, etc.
>
> GL es 73, Mike WA5POK
>
>
> On Friday, September 14, 2018 1:34 PM, Simon Ravnič via Topband <
> topband@contesting.com> wrote:
>
>
> Hi!
>
>
>
> With a head full of browsing and researching I decided to ask for help
> this Topband think tank.
>
>
>
> At S53M contest station we are well organized for 40m & up but are lacking
> lower band TX antennas.
>
>
>
> There are three towers in direction north - south:
> The southern one is 50m high with 40m and 20m monobanders on top
> Middle one is located 25m north of previous one and is 25m high with 15m
> monobander and 6/4m duobander.
> The northern one is 28m north of middle one and is 20m high with Optibeam
> OB17-4.
>
>
> There is a possibility to hang anything between them so I think we would
> prefer some wire antennas. Already present on the site is 160m INV-V and
> 80m vertical dipole from the 50m tower. What we are looking for is 160m and
> 80m TX antenna with two main directions 310 and 45 with low angle radiation.
>
>
>
> RX antennas are OK as there are three 280m long terminated beverages,
> direction 270 (Caribbean), 310 (NA) and 45 (AS).
>
>
>
> To understand better see a photo of the location at
>
> https://www.dropbox.com/s/bk44cg2zfyzpw3w/S53M.JPG?dl=0
>
> or
>
> https://ibb.co/gRPGVU
>
>
>
> Thanks you for your idea & 73
>
> Simon, S53ZO
>
> S53M team
>
>
>
>
>
>
>
>
>
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>
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