How right you are Tom, very well said.
73, Dan KK3AN
W8JI wrote:
> If you look at comparisons or honest reviews of small antennas for
> 160 (or 80) meters, the most efficient ones are universally top
> loaded with some form of large hat or wire and employ reasonably
> large radial systems.
>
> That is why small "(almost) no radials required" verticals like the
> R7, GAP, MFJ and others often work OK on 20 meters or higher.
> They can be mounted so far above earth they are reasonably
> ground independent. But if we look at performance carefully, magic
> "no radial" antennas fall apart very quickly at lower frequencies!
>
> For example the MFJ "no radial" vertical and the GAP vertical are
> among the poorest low band verticals (40 meters and down)
> available, and of course antennas like the Sommer resistor-loaded
> vertical is the standard in poor low-band performance.
>
> The best 160 meter installations on small lots are universally
> inverted L antennas or some form of vertical radiator with top hats
> or top loading and the largest ground system that can fill the small
> yard. Other than that, a low dipole might as well be used.
>
> The worse installations are those with poor or non-existent ground
> systems and too many antennas in a small area, and fancy magic
> feed or loading systems.
>
> Under-performing stations aren't the stations on small lots. They
> are the stations who try to stick too many antennas in a small
> area, or that rely on magic like asymmetrical feeds and "lossless
> loading" schemes and think that three or four radials .05wl above
> ground or less somehow does the trick.
>
> Just when we think it can never get worse?
>
> First we replaced inductors with Q's of maybe 200 or more with
> linear loading stubs with Q's of 40 or less, and called it an
> improvement. We have people convinced that 300 ohms of
> inductive reactance from a coil with a Q of 300 (one ohm loss) is
> less efficient than a 300 ohm reactance stub with a Q of 30 (ten
> ohms loss resistance)!
>
> The latest trend is to replace lossy loading coils and traps and
> even the stubs with pure 100% resistors and tell people by doing
> that they don't need a ground system at all and things get better!
> Now we have Q's of near zero, where reactance is near zero and
> loss resistance is 300, and the best ground systems are those
> with no radials at all.
>
> The twisted logic is with a loading coil or ground system you can't
> have loading coil or ground system loss, and so the electrical equal
> of dummy loads are being sold as superior!
> 73, Tom W8JI
> W8JI@contesting.com
>
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