Eduardo - your arrangement should work well, especially if you place the
main lobe into areas of interest and the "nulls" are into regions of no
activity (or noise sources). It is a good general setup.
Everyone may have their own specific reason for utilizing multiple
Beverages, but mine is very simple. I have nine Beverages that are targeted
to specific areas for specific reasons; End fire Bev's on Europe, one to
JA, one to the Caribbean, one S-SW for LP/skewed Gray Line to the far east,
and so forth. The reason is while a Beverage in a general direction will
work well, in contest times or times when you are trying to pull a very
weak DX station out of the noise that extra 1 dB in pattern improvement
from the Beverage being aimed at a very specific area may make the
difference between a completed Q or a failed one (of course the noise
reduction from other directions is key).
Others may have varying reasons that are just as valid.
Your setup should work well, especially after you install it and begin
comparing signals and making future improvements. My arrangement works well
for me here in Arkansas but is the result of 20 years of tweaking,
rebuilding, reconfiguring, and comparing different RX antenna arrangements
and your efforts will allow you to analyze how things perform at your QTH.
GL.
73 Joel W5ZN
On Fri, Nov 30, 2012 at 1:46 PM, Eduardo Araujo <er_araujo@yahoo.com> wrote:
> Dear Topbanders, I am planning my next move with the beverages and I would
> like to hear your opinions about 2 areas.
>
> Looking at the pattern response for beverages in for example ON4UN book, I
> found that If I install 4 x 600 feet or 5 x 900 feet beverages, I should
> cover 360 degress with deeps of no more than 3 or 4 db respect the main
> lobe.
>
> Taking into account that most people will not work extra without any
> benefit my first question is:
> 1 - Why many DXers and contester install 10 or 12 direction beverages ??
> What am I seriously missing with my simple analysis?
>
> 2 - Is there a meaninfull or simple way to determine if at my location is
> worth to go from 600 to 900 feet?
>
> I did some measurements a) I injected a signal into the beverage and
> using a current probe, I meassure signal strength in an Smeter.(I replaced
> the mA with the input of a transceive)
>
> Variation was about 10db from begining to end of 900 feet. Curiously the
> 600 feet one gave aprox same result but I recognize S meter granularity was
> not good.
>
> b) I disconnected termination resistance and the signal stregth with or
> without it was 8db. 900 feet Bev gives about 20db F/B in broacast band
>
> Many thanks in advance to all
> _______________________________________________
> Topband reflector - topband@contesting.com
>
--
73 Joel W5ZN
www.w5zn.org
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