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[QUOTE=&quot;tballister, post: 46079, member: 5087&quot;]I can't argue with your point that the length of the reflector is close to 1/2 wave resonance.&nbsp; Guess I'm just not sure that its resonant frequency, by itself, is the predominant factor to consider.&nbsp; Isn't it important how much energy at VHF frequencies is reflected off the reflector and captured by the active elements.Here, are some mechanicals for you to ponder:<img src="http://www.antennahacks.com/images/hacks/CM4228HD_VHF_UHF_WaveLengths.png" class="bbImage" alt="" data-url="http://www.antennahacks.com/images/hacks/CM4228HD_VHF_UHF_WaveLengths.png" />Note that 195 MHz and 584 MHz are the median frequencies of the Hi-VHF and (new) UHF bands, respectively.&nbsp; Note also that the horizontal spacing between center points of the active elements is 20.0&quot;, while wavelength at the median UHF frequency of 584 MHz is 20.2&quot;.Just thought it might provoke a thought or two... <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite7" alt=":p" title="Stick out tongue&nbsp; &nbsp; :p" />layball:Regarding off center fed dipoles, I just went to google and entered:&nbsp; &nbsp;&nbsp; off center fed dipole... and got an eyeful.[/QUOTE]

[QUOTE="tballister, post: 46079, member: 5087"]I can't argue with your point that the length of the reflector is close to 1/2 wave resonance. Guess I'm just not sure that its resonant frequency, by itself, is the predominant factor to consider. Isn't it important how much energy at VHF frequencies is [I]reflected [/I]off the reflector and [I]captured [/I]by the active elements. Here, are some mechanicals for you to ponder: [IMG]http://www.antennahacks.com/images/hacks/CM4228HD_VHF_UHF_WaveLengths.png[/IMG] Note that 195 MHz and 584 MHz are the median frequencies of the Hi-VHF and (new) UHF bands, respectively. Note also that the horizontal spacing between center points of the active elements is 20.0", while wavelength at the median UHF frequency of 584 MHz is 20.2". Just thought it might provoke a thought or two... :playball: Regarding off center fed dipoles, I just went to google and entered: off center fed dipole ... and got an eyeful.[/QUOTE]

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