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Amateur Radio Magazine reinforces antenna resonance myth

AR magazine assists in the propagation of myths on the benefits and mechanism of those benefits of antenna resonance in an article that would have appeal for new Foundation Licenced operators, and possibly plenty of old hands.

From an article by Bill Isdale in Nov 2005 AR entitled “Instant gratification”:
Putting up an antenna which is resonant at the desired frequency will produce a high return for our efforts. Resonance is easily achieved, we simply build an antenna of the right size. The reward is that it reacts to signals of that frequency very strongly, giving good performance both radiating and receiving. There is no need for an antenna tuner to mimic for the transmitter the load it was designed to operate into; and no loss in the antenna tuner itself. An antenna tuner, after all, despite its name, does not tune the antenna. Why would you think that, just because of its name? What it actually does is allow an antenna to be used outside the frequency range at which it is resonant. It does this by adding inductance and/or capacitance so that the impedance presented to the radio approximates a 50 ohm resistive load, into which the radio was designed to operate. The result is to make it possible to use the wrong antenna, not to make the antenna the correct size for its task.

Almost everything stated in this one paragraph is arguable. Overall, uninformed and impressionalbe readers would probably get the impression from this one paragraph that:

Articles such as this do not provide building blocks for the development of sound knowledge in our new hams, but it provides a grab back of false knowledge that can be parroted on air by people who don’t have the interest to try to understand the concepts.

Some time ago I wrote an article The importance (or not) of being resonant that explores the importance or otherwise of resonance in antennas.


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