All of the big antenna manufacturers have modeling software by now. So, they
all have a good idea what the gain of their antennas are. It is way past time
for the ARRL to take charge of this problem and set some standards for
antenna gain so we can all make informed decisions on antenna purchases (or
designs for homebrew).
If they would take control of this problem, we could see some believable
antenna gains in advertising and see gains published in QST ads.
Without this important oversight, we have to "wing it" as best we can. In my
own modeling experience, I have found that as gain goes, it is proportional
to boom length in properly designed yagis. In fact, gain differences seem
very closely tied to 8.5 times the log (base 10) of longer boom length
divided by shorter boom length. This would make the KT34XA have 1.06 db more
gain than the TH7DX. W4RNL can give us some input on this aspect of the
problem. What say L.B.?
There is a lot of horsepower in this group. What say some of it be directed
toward the league to suggest they take this problem on? Write your ARRL rep
(or e-mail him) today and do your part for truth in advertising!
73 de Gerald Williamson, K5GW
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