Topband: Vertical array

Mike(W5UC) & Kathy(K5MWH) w5uc at suddenlink.net
Thu Dec 13 08:15:56 EST 2007


At 12:01 AM 12/13/2007, Lee K7TJR wrote:
>      If you are looking at reducing stateside signals (why?) from 
> the rear of a cardiod antenna such as the 2 element you describe I 
> think you should look at selecting the phasing that will best 
> reduce the high angle back lobe that occurs on almost all receiving antennas.

Bingo Lee.  You nailed it!  Looking at the effect of varying the 
phase by a small amount my simple mind said: I don't know the angle 
at which local interference arrives. The only thing I can guestimate 
is the arrival angle of stateside & DX signals, therefore I can 
possibly reduce the overall amount of signal in the receiver front 
end  by increasing the high angle F/B.

>   My experience shows that a 2 element vertical array will most 
> often outperform most loop type antennas in terms of front to back 
> and RDF for DX.

Bingo again!  While using the K9AY array allows me to hear stuff I 
never dreamed was on the band,  I find in reading info from you & 
Tom, and by varying the parameters in the EZ-Nec model,  that I can 
hopefully take the next step up and improve my ability to hear.  It's 
no secret that living here in town on a modest city lot forces us to 
squeeze everything we can out of what we have to work with.  It does, 
however, also provide the opportunity to learn, and that's as much a 
benefit as the improved ability on the air.

What I think would be interesting would be the ability to remotely 
vary the phase of the delay line by a few degrees +/- and attempt to 
optimize the S/N ratio from the antenna  by accounting for the 
varying conditions around my location, say at different times of the 
year when the leaves are on & off the trees.  OR, would that be not 
worth the effort.  Unfortunately, I'm not smart enough to know how to 
do that even if it were worth the effort.

Thanks for the response.

73,
Mike, W5UC

"age & treachery will overcome youth & skill"
http://www.suddenlink.net/pages/w5uc/ 


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