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http://www.dx-antennas.com/Height versus take off angle.htm

good reading on height of dipoles TOA

http://www.hamuniverse.com/wb4yjtdipolepatterns.html

,25 WL AGL is the NVIS cloud warmer,,notice the only lobe going to the clouds.
Whoever posted height is might for local coms on lower bands needs to review radiation pattern vs height AGL.

C&P

The precise height above ground for the very best NVIS performance is not a well-agreed value. Antenna models reported by Jack Swinden W5JCK (and based on work of L.B. Cebik W4RLN) seem to point to best performance on 40-meters at 0.175 wavelength (7 meters, ~21.7 feet) above ground, and on 80-meters a height of 0.165 wavelength (13 meters, ~41 feet). Pat Lambert WØIPL has conducted extensive objective data collection in Colorado and reports an experience of better coverage with a height of only 1/20 wavelength above ground. He notes that noise is significantly reduced as the antenna is lowered below 1/8 wavelength, and that communications with close stations (up to 300 miles away) was greatly enhanced with such low antenna height, particularly using the 80-meter band.

You want NVIS,,keep that wire low to the ground

<blockquote data-quote="wavrider" data-source="post: 589254" data-attributes="member: 9893"><a href="http://www.dx-antennas.com/Height%20versus%20take%20off%20angle.htm" target="_blank">http://www.dx-antennas.com/Height versus take off angle.htm</a>good reading on height of dipoles TOA<a href="http://www.hamuniverse.com/wb4yjtdipolepatterns.html" target="_blank">http://www.hamuniverse.com/wb4yjtdipolepatterns.html</a>,25 WL AGL is the NVIS cloud warmer,,notice the only lobe going to the clouds.Whoever posted height is might for local coms on lower bands needs to review radiation pattern vs height AGL.C&amp;PThe precise height above ground for the very best NVIS performance is not a well-agreed value. <a href="http://www.w5jck.com/nvis/W5JCK-NVIS-Antenna-Presentation.pdf" target="_blank">Antenna models reported by Jack Swinden W5JCK</a> (and based on work of L.B. Cebik W4RLN) seem to point to best performance on 40-meters at 0.175 wavelength (7 meters, ~21.7 feet) above ground, and on 80-meters a height of 0.165 wavelength (13 meters, ~41 feet). <a href="http://www.w0ipl.net/ECom/NVIS/nvis.htm" target="_blank">Pat Lambert WØIPL has conducted extensive objective data collection</a> in Colorado and reports an experience of better coverage with a height of only 1/20 wavelength above ground. He notes that noise is significantly reduced as the antenna is lowered below 1/8 wavelength, and that communications with close stations (up to 300 miles away) was greatly enhanced with such low antenna height, particularly using the 80-meter band.You want NVIS,,keep that wire low to the ground</blockquote>

[QUOTE="wavrider, post: 589254, member: 9893"] [URL]http://www.dx-antennas.com/Height%20versus%20take%20off%20angle.htm[/URL] good reading on height of dipoles TOA [URL]http://www.hamuniverse.com/wb4yjtdipolepatterns.html[/URL] ,25 WL AGL is the NVIS cloud warmer,,notice the only lobe going to the clouds. Whoever posted height is might for local coms on lower bands needs to review radiation pattern vs height AGL. C&P The precise height above ground for the very best NVIS performance is not a well-agreed value. [URL='http://www.w5jck.com/nvis/W5JCK-NVIS-Antenna-Presentation.pdf'][U]Antenna models reported by Jack Swinden W5JCK[/U][/URL] (and based on work of L.B. Cebik W4RLN) seem to point to best performance on 40-meters at 0.175 wavelength (7 meters, ~21.7 feet) above ground, and on 80-meters a height of 0.165 wavelength (13 meters, ~41 feet). [URL='http://www.w0ipl.net/ECom/NVIS/nvis.htm'][U]Pat Lambert WØIPL has conducted extensive objective data collection[/U][/URL] in Colorado and reports an experience of better coverage with a height of only 1/20 wavelength above ground. He notes that noise is significantly reduced as the antenna is lowered below 1/8 wavelength, and that communications with close stations (up to 300 miles away) was greatly enhanced with such low antenna height, particularly using the 80-meter band. You want NVIS,,keep that wire low to the ground [/QUOTE]

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