As a matter of facts, a number of yagi antenna designs popular on the
70' and 80' were far to be really optimized, and this explains why
antenna shapes (spacings, lenghts) and results of different individuals
have been that times so different with similar boom lenghts.
Sometimes the claimed gain figures approached reality, some other times
the claimed gain followed desires, and the gain or F/B "numbers" were
more proportional to the time spent in time consuming "cut and try
procedures" than close reality.
Height from ground and gain at peculiar elevations is another
fundamental topic which didn't benefit a real follow up that times, and
often the "magical" antennas properties were mostly because of the
installation rather than because of inherent antenna gain.
Average antennas and installations were enough poor in terms of real
gain (even a trapped tribander was not so common yet) and the few Hams
with "real" yagi monobanders (or quads) and "real" towers (or peculiar
locations) did emerge very much from the mass.
Twenty years later, with the aid of computer antenna analisis is quite
normal to evaluate and trust gain figures and compare designs if who
design the model is skilled (experienced) enough and uses his brain, at
least in a free space condition, and if one is not blind, yagi antennas
of different manufacturersare now quite.
What's the max gain achievable for a stated boom lenght is already a
public domain stuff and practically any yagi is evaluable with a small
alea.
As well as the above, what's the gain of a square 1WL loop over a
simple dipole or what's gained in a yagi array using hybrid quad and
straight tubing elements is perfectly evaluable.
73,
Mauri I4JMY
> ---------- Initial message -----------
>
> From : owner-towertalk@contesting.com
> To : towertalk@contesting.com
> Cc :
> Date : Fri, 9 Feb 2001 08:02:56 +0100
> Subject : [TowerTalk] re: quad
>
>
> Didn´t K3BU make the statement that his razor was 10 dB better
> then the 6L KLM and the KLM was 10 dB better then the 5L Telerex?
> Result would be that the razor thing was 20 dB better then the
> Telerex, and 30 better then a dipole would follow the same reasoning.
> Why pick on W8JI, I saw this in print myself , so Yuri if you feel
> like picking on people you might as well pick on me too.
> Now, if those razor whiz things are so good why not publish the
> data? If I would have come up with something that good I would
> have been proud to publish it.
> In any case, clames like the above I don´t belive at all, they
belong
> in
> some kind a dream world, ohhh just remembered that back in the
> seventies smoking weed was very common in the states, hmmmm
>
> 73, Jim SM2EKM
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