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BJ and Homer, I think the difference that BJ suggested about Bill Orr's book is considering the difference between results from a Free Space model, with all the losses removed, and a Real Earth model, with losses included in the model.

There is a bit of difference between modeling technology 44 years ago and today, but there is very little difference in the results.

I included two images of the end dimensions so we can calculate the Moxon spacing in this case. Add the mumbers to the 5.86" end gap and you get 57.25" inches for the spacing.

57.25 / 433.849 Eznec wavelength at 27.205 MHz and we see a compromise ratio of 0.13 wavelength spacing. IMO this is probably done to maintain the nice bandwidth to gain values with the caluclators.

The overlays at the end show the pattern differences.

<blockquote data-quote="Marconi" data-source="post: 751294" data-attributes="member: 903">BJ and Homer, I think the difference that BJ suggested about Bill Orr&#039;s book is considering the difference between results from a Free Space model, with all the losses removed, and a Real Earth model, with losses included in the model.There is a bit of difference between modeling technology 44 years ago and today, but there is very little difference in the results.I included two images of the end dimensions so we can calculate the Moxon spacing in this case. Add the mumbers to the 5.86&quot; end gap and you get 57.25&quot; inches for the spacing. 57.25 / 433.849 Eznec wavelength at 27.205 MHz and we see a compromise ratio of 0.13 wavelength spacing. IMO this is probably done to maintain the nice bandwidth to gain values with the caluclators. &nbsp;The overlays at the end show the pattern differences.&nbsp;</blockquote>

[QUOTE="Marconi, post: 751294, member: 903"] [SIZE=5]BJ and Homer, I think the difference that BJ suggested about Bill Orr's book is considering the difference between results from a Free Space model, with all the losses removed, and a Real Earth model, with losses included in the model. There is a bit of difference between modeling technology 44 years ago and today, but there is very little difference in the results. I included two images of the end dimensions so we can calculate the Moxon spacing in this case. Add the mumbers to the 5.86" end gap and you get 57.25" inches for the spacing. 57.25 / 433.849 Eznec wavelength at 27.205 MHz and we see a compromise ratio of 0.13 wavelength spacing. IMO this is probably done to maintain the nice bandwidth to gain values with the caluclators. The overlays at the end show the pattern differences. [/SIZE] [/QUOTE]

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