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Some antenna impedances are well known, such as the quarter wave whip (with horizontal radials) and a half wave dipole. Others you have to do more research on.

Typically most antennas I see are quarter wavelength or shortened quarter wavelength antennas, which will give you an impedance at resonance between 10 and 36 ohms, which is between 5:1 and 1.38:1 SWR. An exception here is some base loaded antennas will use a capacitor along with the base load to try and better match to the 50 ohm feedline at resonance.

Many base antennas you can adjust resonance and impedance separately, those and the quarter wavelength verticals with angled radials are typically the antennas that can be tuned for both resonance and impedance at the same time and present a perfect 1:1 match for the right reasons.

I am under the impression that you could use modeling to make the determinations as well, I bring this up because you are a modeler. Unfortunately I am not, at least, not yet...

The DB

<blockquote data-quote="The DB" data-source="post: 429764" data-attributes="member: 21346">Some antenna impedances are well known, such as the quarter wave whip (with horizontal radials) and a half wave dipole.&nbsp; Others you have to do more research on.Typically most antennas I see are quarter wavelength or shortened quarter wavelength antennas, which will give you an impedance at resonance between 10 and 36 ohms, which is between 5:1 and 1.38:1 SWR.&nbsp; An exception here is some base loaded antennas will use a capacitor along with the base load to try and better match to the 50 ohm feedline at resonance.Many base antennas you can adjust resonance and impedance separately, those and the quarter wavelength verticals with angled radials are typically the antennas that can be tuned for both resonance and impedance at the same time and present a perfect 1:1 match for the right reasons.I am under the impression that you could use modeling to make the determinations as well, I bring this up because you are a modeler.&nbsp; Unfortunately I am not, at least, not yet...<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 429764, member: 21346"] Some antenna impedances are well known, such as the quarter wave whip (with horizontal radials) and a half wave dipole. Others you have to do more research on. Typically most antennas I see are quarter wavelength or shortened quarter wavelength antennas, which will give you an impedance at resonance between 10 and 36 ohms, which is between 5:1 and 1.38:1 SWR. An exception here is some base loaded antennas will use a capacitor along with the base load to try and better match to the 50 ohm feedline at resonance. Many base antennas you can adjust resonance and impedance separately, those and the quarter wavelength verticals with angled radials are typically the antennas that can be tuned for both resonance and impedance at the same time and present a perfect 1:1 match for the right reasons. I am under the impression that you could use modeling to make the determinations as well, I bring this up because you are a modeler. Unfortunately I am not, at least, not yet... [URL="http://hittman.us"][COLOR="Black"]The DB[/COLOR][/URL] [/QUOTE]

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