Pete Smith wrote:
> I'm amazed that there hasn't yet been any discussion of N6LF's article.
> His tests appear to demolish a lot of fondly-held beliefs (certainly
> including my own), and to point the way to a better topband signal in
> return for low cost and effort. I'm a recovering history major, though,
> and I think all of us would profit from some active technical discussion
> of the subject. How about it?
>
I've had a lot of private discussions with N6LF about these tests.
First of all, let me say that, unlike many other QST antenna articles,
you can actually believe this one. Rudy did his measurements the
right way. For once I didn't have any suggestions about how the
measurements could have been done better :-) Be sure to read the
supplementary material on the web.
Also, the article may appear to give the go ahead to use elevated
radials. Well, yes and no. Four elevated radials, perfectly tuned,
will work quite well on their design frequency. However, 8 or 16
elevated radials is a lot less critical. So it is more like 16
elevated radials work a little better than 16 on the ground.
Also, the surprise about shorter radials being better than quarter
wave radials is mainly about when you only have 4 radials on the ground.
Finally, these tests are over Rudy's QTH. Like they say YMMV.
I think what we need now is a how-to article on doing 4 elevated
radials CORRECTLY and what the limitations (mainly bandwidth) are.
It is really easy to screw up 4 elevated radials, unlike 32 radials
on the ground.
It probably doesn't come across in the article just how much hard work
Rudy did to produce this data. We should be very appreciative of his
effort.
Rick N6RK
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