All,
Two cents worth of comments on thread. The SAL, K9AY and Waller Flags
all work well and have their limitations. They do help the city folk
improve the ability to receive. The WF works great if you can get it up
in the air and rotate it. That is if you can keep it there in one piece
though snow , ice and wind. It also encompasses additional costs for
tower support and rotator.
The larger passive and active arrays specifically 8 circle provided you
have space are better yet with great RDF, realistic gain and noise figures.
There is a cross over point where there is no longer any improvement
IMHO. I'll point out an example. In the morning hours before sun rise my
noise floor drops to near zero on my RX/TX array. I'm extremely
fortunate for I have the space and no neighbors, no commercial power and
thus only natural noise. A reasonable guess would be a noise floor
greater than -120 to -125dB. Almost to the point of MDS where there is
no indicated or measured difference between antenna and no antenna.
Working signals via polar path, NW, West and SE are _on average very
very weak._
My experience tells me that active loops would be inferior to the
existing directional RX/TX antenna at this point because of their signal
capture levels and increased noise created by preamplifier. In this case
only long properly terminated and maybe phased beverages would be better.
I can feel the heat coming on this one. I'm not here to sell antennas as
I build my own.
73 and Happy New Year!
Bob, W7RH
--
W7RH DM35OS
It has become appallingly obvious that our technology has exceeded our humanity.
Albert Einstein
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