Myths and facts

Some common myths about antennas.

http://www.k0bg.com/myths.html

Interesting read. Thanks for sharing.

Nice link Phil.

In one camp we get the theoretical and calculated understanding and in the other the observable effects.....someone just needs to link up the two and we'd be a happy bunch

(Had right fun researching Terminated Butterfly Dipoles recently!)

Victor wrote:

Nice link Phil.

In one camp we get the theoretical and calculated understanding and in the other the observable effects.....someone just needs to link up the two and we'd be a happy bunch

(Had right fun researching Terminated Butterfly Dipoles recently!)

Hate to think how much wire I've gone through doing just that, coming up with an idea or seeing something, modelling it then building it to see how it compared.

One of the most interesting ones was playing with an inverted L. Using 25ft vertical and 60ft flat top, reducing the flat top length by just 5ft dramatically altered the azimuth pattern on the 20m band turning it from an apple shape to a cross. I could see the effect testing it on one orientated north/south by how much it attenuated the caconophy from Europe and increased signals from North/South America when the length was changed. It worked so well I investigated the possibility of putting in a relay to switch in and out the extra length.

Hi Conor,

Nice one mate, good to hear antenna experimenters comparing computer modelling to real world results.

It's when the two are married together that modelling software becomes better and more reliable at predicting results. It's all too easy to 'armchair warrior' datasets or stand with a closed mind of only practical experience and no-one gets anywhere. I also think sales pitches with exaggerated claims are by far the worst myth perpetuaters.

I applaud people like yourself with a passion to experiment and share knowledge even if faced with adversity, (antennas are weirdly still a contentious subject!)

I did finally find a good resource for terminated dipole antennas with Bonnie Crystal KQ6XA, another passionate experimenter who has stuck with it and shared her knowledge despite some rebuttals

Nice one

Victor wrote:

Nice link Phil.

In one camp we get the theoretical and calculated understanding and in the other the observable effects.....someone just needs to link up the two and we'd be a happy bunch

(Had right fun researching Terminated Butterfly Dipoles recently!)

Most people in this hobby seriously misunderstand the relationship between theory and reality.  When it comes to antennas, theory is is nothing more than an explanation (perhaps reflection would be a better word here) of reality.  If you see something that you think theory doesn't explain, the truth is your understanding of theory is what is lacking.  Don't be disheartened by this, antenna theory at its purest level is very complex, requiring a rather extensive understanding of trigonometry and calculus to truly understand what is going on.  Very few people outside of scientists and engineers ever get to this point.

Many concepts in antenna theory seem easy to grasp on the surface, however, like the English language, there is no rule that doesn't have its exception.  The more general the statement, the more exceptions it tends to have.  If someone uses "all", "always" or "never" when referring to antennas, beware, their is an exception, and generally more than one.

This leads to myths that many use and in some cases fervently believe with religious like vigor.  Like lies, the most believable myths have some aspect of truth to them.  This kernel of truth makes said myths much more difficult to debunk.

Some very knowledgeable people are often surprised at my solutions, solutions that not only work very well, but also go directly against what they think should happen, one of which swears that I use "black magic" to make antennas work...


The DB