[TowerTalk] RX antenna for 30, 40 (and 80)

[KC1DI]

On 9/21/06, Geert Hofman <Geert_Hofman at jabil.com> wrote:
>
> Folks,
>
>
>
> I have been doing some (antenna) garden work and have now installed a
> full size vertical for 40 (again). I will be installing a half loop for
> 80 m and also a delta loop for 30 m.
>
>
>
> But especially for 30 & 40 , my RX is (and has always been) covered with
> tremendous noise. In TX I have no problems , whatever I hear I can
> mostly work, but I want to improve my RX. Now having admired the
> beverage set up at ON4UN who lives about 5 miles from me, and having
> read almost everything on RX antennas, I was wondering what you guys
> would recommend for 30 & 40 m RX, because most of the things are aimed
> at 80 and 160 m. I have no interest at all in top band and am not
> expecting too much from 80 , but I like 30 & 40 .
>
>
>
> My plot is 20 m x 50 m ( 70 ft x 170 ft ), but cannot use any guying (
> because it's also children's playground), and difficult to put things in
> the middle. Also for additional supports/.., I am restricted to about 25
> ft for fixed set ups of tubing. But I have 2 40 ft fibreglass masts (
> spiderbeam ). I have been looking at a beverage about 170 ft long  a
> K9AY, a low dipole  ( inv V at 25 ft apex), a horizontal rectangular
> loop at 20 to 25 ft average height  following the contours of the plot,
> a vertical parasitic array.. but I am not quite sure what to take as a
> good RX DX antenna specifically for 40 & 30 m. Alternatively I am
> contemplating to install a 40/30 m dipole on top of my tribander (
> stacking only 3' possible), and although I think this is the best
> solution, I am concerned about windload of this configuration for my
> mast. Also still looking for a good design of a 30/40 trapped dipole
> with max wingspan of about 10 meters, which is not too heavy...
>
>
>
> I wonder what you would suggest me to do. BTW, I do not live an urban
> environment and have average to good soil conductivity and in many
> directions, especially from SW over N to SE "free sight". I am also on
> one the highest spots of the area (albeit only 200 ft ASL !).
>
>
>
> Looking forward to your valued input !
>
>
>
> Geert - ON4IG - OQ5A
>
>
>
> Hi Geert,



Wonder if you have tried to track down the noise source?
It may be easier than trying to build another antenna in your situation.
However with that said I would investigate a small rx loop of some sort..
the beverage needs to be much longer than 170 ft in order to really work..
and on 40 & 30 Meters needs to be quite low to the ground.

With an rx loop it is often useful in nulling out local interference.

Let us know what you finally come up with and how it works.
73 Dave KC1DI