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That is what I was thinking, however Marconi's modeling software came up with a different figure.

I've seen several graphs while looking through my available resources, and for 0.25 wavelength they all show a little above a 35 ohm radiation resistance. In most cases this is meant to be a baseline before factoring in things like height, width, inadequate ground plane, ect. I have yet to see any math to get to the 35 to 37 ohm figures that are used to make the graphs, and one source specifically states that their information was found via using quarter wavelength vertical antennas with 120 half wavelength or longer radials and real world measurements.

I was hoping for something a little more specific on the theory side, such as the formula used for the graphs, to reference but if it exists I haven't found it yet...

The DB

<blockquote data-quote="The DB" data-source="post: 441119" data-attributes="member: 21346">That is what I was thinking, however Marconi&#039;s modeling software came up with a different figure.I&#039;ve seen several graphs while looking through my available resources, and for 0.25 wavelength they all show a little above a 35 ohm radiation resistance.&nbsp; In most cases this is meant to be a baseline before factoring in things like height, width, inadequate ground plane, ect.&nbsp; I have yet to see any math to get to the 35 to 37 ohm figures that are used to make the graphs, and one source specifically states that their information was found via using quarter wavelength vertical antennas with 120 half wavelength or longer radials and real world measurements.I was hoping for something a little more specific on the theory side, such as the formula used for the graphs, to reference but if it exists I haven&#039;t found it yet...<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 441119, member: 21346"] That is what I was thinking, however Marconi's modeling software came up with a different figure. I've seen several graphs while looking through my available resources, and for 0.25 wavelength they all show a little above a 35 ohm radiation resistance. In most cases this is meant to be a baseline before factoring in things like height, width, inadequate ground plane, ect. I have yet to see any math to get to the 35 to 37 ohm figures that are used to make the graphs, and one source specifically states that their information was found via using quarter wavelength vertical antennas with 120 half wavelength or longer radials and real world measurements. I was hoping for something a little more specific on the theory side, such as the formula used for the graphs, to reference but if it exists I haven't found it yet... [URL="http://hittman.us"][COLOR="Black"]The DB[/COLOR][/URL] [/QUOTE]

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