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I took a look at an idea and an observation that was mentioned earlier, and that is the appearance of a 1/2 wavelength radiation pattern on a 1/4 wavelength section of antenna. I do kindof see it as well, however the operative word is kindof.

Anyway, the possible explanation given by Donald (I think it was him) thinking it was due to the interaction of multiple currents combining on the basket radials. This idea can be tested, rather easily actually, using a simple spread sheet and its charting feature.

What I did is create a sine wave on a chart in the spreadsheet by having the spreadsheet calculate the sine of every degree from 0 to 360. I then created a second sine wave that was, in the examples below 90 degrees out of phase. It created a chart that looks like this:

Lets say for this purpose that this represents the current strength and phase of two separate sine waves that are not in phase on a single antenna element. When multiple currents exist from separate signals on a single wire at any given point the currents add. Because of this I added the currents present in every degree of both sine waves and this is what I got:

We get a new sine wave that has the same frequency as the others. The amplitude of the currents of this new sine wave is dependent on the phase relationship of the sine waves that created it. The closer their phase relationship the stronger the amplitude of the new sine wave. However and critically, the frequency does not change. I did this same test with varying phases and predictable results.

I did the same test with three four and five sign waves and adding them all together, the results are the same, a single sine wave with the same frequency results, so no matter what you do as long as the frequencies being considered are all the same you get a result of only that frequency. Therefore according to this test the 1/2 wavelength pattern on 1/4 wavelength of antenna simply cannot be... However...

However, after some thinking I have discovered that this test has a critical flaw that changes everything. Can anyone guess what that flaw is? I'll give you a hint, it is in the writings (at least the books) of M. Walter Maxwell...

The DB

<blockquote data-quote="The DB" data-source="post: 498344" data-attributes="member: 21346">I took a look at an idea and an observation that was mentioned earlier, and that is the appearance of a 1/2 wavelength radiation pattern on a 1/4 wavelength section of antenna.&nbsp; I do kindof see it as well, however the operative word is kindof.Anyway, the possible explanation given by Donald (I think it was him) thinking it was due to the interaction of multiple currents combining on the basket radials.&nbsp; This idea can be tested, rather easily actually, using a simple spread sheet and its charting feature.What I did is create a sine wave on a chart in the spreadsheet by having the spreadsheet calculate the sine of every degree from 0 to 360.&nbsp; I then created a second sine wave that was, in the examples below 90 degrees out of phase.&nbsp; It created a chart that looks like this:<img src="http://hittman.us/pictures/10-14-14/test1.jpg" alt="" class="fr-fic fr-dii fr-draggable " data-size="" style="" />Lets say for this purpose that this represents the current strength and phase of two separate sine waves that are not in phase on a single antenna element.&nbsp; When multiple currents exist from separate signals on a single wire at any given point the currents add.&nbsp; Because of this I added the currents present in every degree of both sine waves and this is what I got:<img src="http://hittman.us/pictures/10-14-14/test2.jpg" alt="" class="fr-fic fr-dii fr-draggable " data-size="" style="" />We get a new sine wave that has the same frequency as the others.&nbsp; The amplitude of the currents of this new sine wave is dependent on the phase relationship of the sine waves that created it.&nbsp; The closer their phase relationship the stronger the amplitude of the new sine wave.&nbsp; However and critically, the frequency does not change.&nbsp; I did this same test with varying phases and predictable results.I did the same test with three four and five sign waves and adding them all together, the results are the same, a single sine wave with the same frequency results, so no matter what you do as long as the frequencies being considered are all the same you get a result of only that frequency.&nbsp; Therefore according to this test the 1/2 wavelength pattern on 1/4 wavelength of antenna simply&nbsp; cannot be...&nbsp; However...However, after some thinking I have discovered that this test has a critical flaw that changes everything.&nbsp; Can anyone guess what that flaw is?&nbsp; I&#039;ll give you a hint, it is in the writings (at least the books) of M. Walter Maxwell...<a href="http://hittman.us" target="_blank">The DB</a></blockquote>

[QUOTE="The DB, post: 498344, member: 21346"] I took a look at an idea and an observation that was mentioned earlier, and that is the appearance of a 1/2 wavelength radiation pattern on a 1/4 wavelength section of antenna. I do kindof see it as well, however the operative word is kindof. Anyway, the possible explanation given by Donald (I think it was him) thinking it was due to the interaction of multiple currents combining on the basket radials. This idea can be tested, rather easily actually, using a simple spread sheet and its charting feature. What I did is create a sine wave on a chart in the spreadsheet by having the spreadsheet calculate the sine of every degree from 0 to 360. I then created a second sine wave that was, in the examples below 90 degrees out of phase. It created a chart that looks like this: [IMG]http://hittman.us/pictures/10-14-14/test1.jpg[/IMG] Lets say for this purpose that this represents the current strength and phase of two separate sine waves that are not in phase on a single antenna element. When multiple currents exist from separate signals on a single wire at any given point the currents add. Because of this I added the currents present in every degree of both sine waves and this is what I got: [IMG]http://hittman.us/pictures/10-14-14/test2.jpg[/IMG] We get a new sine wave that has the same frequency as the others. The amplitude of the currents of this new sine wave is dependent on the phase relationship of the sine waves that created it. The closer their phase relationship the stronger the amplitude of the new sine wave. However and critically, the frequency does not change. I did this same test with varying phases and predictable results. I did the same test with three four and five sign waves and adding them all together, the results are the same, a single sine wave with the same frequency results, so no matter what you do as long as the frequencies being considered are all the same you get a result of only that frequency. Therefore according to this test the 1/2 wavelength pattern on 1/4 wavelength of antenna simply cannot be... However... However, after some thinking I have discovered that this test has a critical flaw that changes everything. Can anyone guess what that flaw is? I'll give you a hint, it is in the writings (at least the books) of M. Walter Maxwell... [URL='http://hittman.us'][COLOR=#000000]The DB[/COLOR][/URL] [/QUOTE]

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