Resonant Frequency Often Not Lowest SWR (

John, AD8IQ, has a question. Which is more important in an antenna system, the lowest SWR or the 50 ohm impedance? Watch to learn which one I hink is better to have.
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[@AC3HT]

Thanks, Dave. Even after 30 years in the hobby, radio always amazes me. Great video explaining the often times unexplainable. 73, AC3HT

[@timmack2415]

I think this raises more questions than it answers, in my opinion

[@RESISTAGE]

I noticed while operating on 2m while the antenna is resonant, the SWR is high like 4/1 or even 5/1
it gets more higher as power increased.

[@montybates5176]

Another great video. Thanks Dave!

[@electronics.unmessed]

Many thanks for the clarification! It is what it is. But an impedance transformation network can help in case the antenna impedance is too far from 50 Ohms.

[@southernexposure123]

Thank you for the explanations. I have a few questions. When the reactance is tens of Khz from the lowest SWR is it worthwhile to work toward adding some coil / capacitor combination to set the reactance to zero on the frequency of lowest SWR? IF so, what calculations should be done to accomplish that?
Maybe you've guessed I have an interest in QRP.
Thank you again for your time.

[@MrApolloTom]

Hi Dave, I'm a bit unclear what the resonant frequency of the antenna means here. In another video you said it means when the reactive part of the impedance is zero. Here you suggest it means at a half wavelength size even if there is some reactance.

[@xntumrfo9ivrnwf]

Hi Dave, do you perhaps have a link to the slides you're reading from? I've checked your website but can only find the (excellent) presentation video. The slides themselves would be super helpful!

[@jdecar1]

1. Would the tuning strategy change for a listening-only antenna? Tune for resonance in that case?
2. Could you get resonance & SWR to align better by changing the antenna height, or perhaps just raising the center some amount (like an inverted V), to adjust the impedance?

[@ricksshop]

I can answer #2 because I went through this. When erecting my homebuilt 20/40 meter fan dipole (which is now a 20/40/80 dipole with coax traps in the 80 meter legs for 20 meters, but that's a different story), impedance of this inverted V dipole 28 feet off the ground was too low. So yes, antennas that are closer to the ground (or large metallic objects) or that have high angle in the "V" will show lower impedance than antennas higher off the ground or that have less angle in the "V". My solution? Feed the thing slightly off center to raise the impedance to a more radio-friendly range.

[@SkyWire88]

Tunes off.... ?

[@criscross6591]

👍👍

[@BusDriverRFI]

If you have an impedance load of 50+j0, your swr will be 1:1 by definition.

[@wynandwolmarans6689]

True dummy load is 1.1or 0
Resonant is not allways wht we think x close to 0