At 06:32 PM 12/19/02 +1300, Greg - ZL3IX wrote:
>The two are almost identical in directivity, which is the
>important parameter for noise reduction. If the pennant is easier to erect,
>stick with it.
Greg and Charles,
On a computer screen, in free space, or out in the country where you don't
need them, the flag and pennant are essentially identical in performance.
But, like most topband issues, "there ain't no free lunch".
I have found, through extensive A/B testing, that the flag is indeed a
better performer in a space limited urban settings. It has shown, at least
to me, that it has less susceptibility to interaction from nearby objects
such as other antennas, fences, buildings, etc. This usually results in
several dB improvement in S/N.
This difference is small, on the order of 2-3 dB, and most operators would
never be able to tell the difference with out A/B testing. Also, it would
seem that a lot of operators would gladly trade off a few dB for ease of
construction. Everything is a compromise and sometimes I will use the
pennant myself if the flag is not convenient.
Only the operator putting out the effort can determine if it's worth it,
however it's good to have all the facts before making that decision.
73,
Larry - W7IUV
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