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And there was me thinking 1/2 waves were resonant. 1 wavelength also would shout that it is resonant to me. I always considered something that was 1 wavelength long to be resonant as a wavelength of RF is an identical length to the radiating element.

Now I question if I even have the correct meaning of resonance when it comes to antennas. (Though thinking about it it must be the same as any tuned circuit, when Xc and Xl are equal)

From the above it seems if reactance can be 0 then an antenna is resonant. I have never used analyzers as I never seen them as necessary (owning an SWR capable radio) making known designs I have not gone into the definition more than was required to pass an exam.

I agree a 3/4 wave is a poor antenna for DX compared to a 5/8 wave in the models I have produced.

Electrically 90 degrees is very small is an interesting statement. It's big enough to cause increased calculation complexities in capacitors and inductors... small compared to what ?

A 1/4 wave is current fed but why is a 1/4 wave resonant ? Surely it has the same voltage and current phase difference as any of the other antennas (90 degrees) I can only imagine that by virtue of it being current fed something is happening to allow capacitance and inductance to be equal in that design.

Edited to add : Ok the penny has dropped I think... no matching required = resonant antenna.. if you need matching circuit it is not resonant.

<blockquote data-quote="TheBlaster" data-source="post: 775909" data-attributes="member: 58745">And there was me thinking 1/2 waves were resonant. 1 wavelength also would shout that it is resonant to me. I always considered something that was 1 wavelength long to be resonant as a wavelength of RF is an identical length to the radiating element.Now I question if I even have the correct meaning of resonance when it comes to antennas. (Though thinking about it it must be the same as any tuned circuit, when Xc and Xl are equal)From the above it seems if reactance can be 0 then an antenna is resonant. I have never used analyzers as I never seen them as necessary (owning an SWR capable radio) making known designs I have not gone into the definition more than was required to pass an exam.I agree a 3/4 wave is a poor antenna for DX compared to a 5/8 wave in the models I have produced.Electrically 90 degrees is very small is an interesting statement. It&#039;s big enough to cause increased calculation complexities in capacitors and inductors... small compared to what ?A 1/4 wave is current fed but why is a 1/4 wave resonant ? Surely it has the same voltage and current phase difference as any of the other antennas (90 degrees) I can only imagine that by virtue of it being current fed something is happening to allow capacitance and inductance to be equal in that design.Edited to add : Ok the penny has dropped I think... no matching required = resonant antenna.. if you need matching circuit it is not resonant.</blockquote>

[QUOTE="TheBlaster, post: 775909, member: 58745"] And there was me thinking 1/2 waves were resonant. 1 wavelength also would shout that it is resonant to me. I always considered something that was 1 wavelength long to be resonant as a wavelength of RF is an identical length to the radiating element. Now I question if I even have the correct meaning of resonance when it comes to antennas. (Though thinking about it it must be the same as any tuned circuit, when Xc and Xl are equal) From the above it seems if reactance can be 0 then an antenna is resonant. I have never used analyzers as I never seen them as necessary (owning an SWR capable radio) making known designs I have not gone into the definition more than was required to pass an exam. I agree a 3/4 wave is a poor antenna for DX compared to a 5/8 wave in the models I have produced. Electrically 90 degrees is very small is an interesting statement. It's big enough to cause increased calculation complexities in capacitors and inductors... small compared to what ? A 1/4 wave is current fed but why is a 1/4 wave resonant ? Surely it has the same voltage and current phase difference as any of the other antennas (90 degrees) I can only imagine that by virtue of it being current fed something is happening to allow capacitance and inductance to be equal in that design. Edited to add : Ok the penny has dropped I think... no matching required = resonant antenna.. if you need matching circuit it is not resonant. [/QUOTE]

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