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ARRL Antenna book : "Where the current and voltage are exactly in phase, the impedance is purely resistive with zero reactance and the antenna is resonant"

By what means is V and I phase changing in a 1/4 wave by 90 degrees to make it purely resistive ? (compared to any other antenna)

I know quarter wavelengths can be significant in creating sleeve balun's and impedance matching but cannot think why I and V change phase just because wire happens to be a 1/4 wave of the freqeuncy you are sticking up it.

Something is not adding up in this ARRL statement as we know for a 1/4 and a 1/2 wave "I max" is in centre and volts are higher at the end of the antenna. That does not appear to be the definition of "in phase" as far as I understand it.

[QUOTE="TheBlaster, post: 776118, member: 58745"] ARRL Antenna book : "Where the current and voltage are exactly in phase, the impedance is purely resistive with zero reactance and the antenna is [I]resonant[/I]" By what means is V and I phase changing in a 1/4 wave by 90 degrees to make it purely resistive ? (compared to any other antenna) I know quarter wavelengths can be significant in creating sleeve balun's and impedance matching but cannot think why I and V change phase just because wire happens to be a 1/4 wave of the freqeuncy you are sticking up it. Something is not adding up in this ARRL statement as we know for a 1/4 and a 1/2 wave "I max" is in centre and volts are higher at the end of the antenna. That does not appear to be the definition of "in phase" as far as I understand it. [/QUOTE]

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