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[QUOTE=&quot;Piggie, post: 22032, member: 2941&quot;]Ah, you were there, and I may have asked the question bad. The maximum radiation of any vertical is at some angle between 90 degrees (orthogonal to the whip)&nbsp; and all verticals have zero (well it approaches an asymptote) off the end of the vertical (provided it's a pure vertical radiation, ie no capacitance hat).&nbsp; So if you look at the vertical from space the radiation looks like a doughnut.Now just like stacking antennas in phase the radiation from each if spaced correctly will add to create at some angle to the antenna there is more radiation (hence less somewhere else) and we call that gain.&nbsp; Adding two antennas is like the 2 slit experiment some of you may have done in physics class, where there is a bright spot on the wall between the slits (where there is no slit) cause by the summing of the waves passing through the two slits. Now since a 1/4 wave maximum current is at the base of the antenna near the feed point it's maximum radiation above a good ground plane is about 25 degrees above the horizon.&nbsp;&nbsp; Now think of an end feed 1/2 wave as two stacked 1/4 waves.&nbsp; Since the antenna is feed at a high impedance point where the current is very low, all the energy is &quot;pushed&quot; into the antenna by an electric field.&nbsp; As the signal approaches the center of the antenna the current builds to a maximum at the center.&nbsp; Now the strongest magnetic field is created where the current is maximum as shown by Maxwell.&nbsp; Hence thinking of a 1/2 vertical as two 1/4 waves stacked, the current is maximum at the top part of the bottom half and the bottom part of the top half.&nbsp; Hence why I say it's very close spaced stacked verticals.&nbsp; Still there is some gain.&nbsp; There is a about .85 db increase from the &quot;stacking&quot;.&nbsp; This lowers the radiation maximum to about 20 degrees.So with lower radiation maximum, more signal is receive or transmitted closer to the horizon where the signal from distance stations is also maximum.Though only .85 db gain (over a 1/4 wave vertical) it will appear one is doing better than that.&nbsp; This is because the antenna is then aligning with the maximum signal coming from the horizon. After that much typing I hope I kept to the point and answered my own question.&nbsp; <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite4" alt=":mad:" title="Mad&nbsp; &nbsp; :mad:" />)[/QUOTE]

[QUOTE="Piggie, post: 22032, member: 2941"]Ah, you were there, and I may have asked the question bad. The maximum radiation of any vertical is at some angle between 90 degrees (orthogonal to the whip) and all verticals have zero (well it approaches an asymptote) off the end of the vertical (provided it's a pure vertical radiation, ie no capacitance hat). So if you look at the vertical from space the radiation looks like a doughnut. Now just like stacking antennas in phase the radiation from each if spaced correctly will add to create at some angle to the antenna there is more radiation (hence less somewhere else) and we call that gain. Adding two antennas is like the 2 slit experiment some of you may have done in physics class, where there is a bright spot on the wall between the slits (where there is no slit) cause by the summing of the waves passing through the two slits. Now since a 1/4 wave maximum current is at the base of the antenna near the feed point it's maximum radiation above a good ground plane is about 25 degrees above the horizon. Now think of an end feed 1/2 wave as two stacked 1/4 waves. Since the antenna is feed at a high impedance point where the current is very low, all the energy is "pushed" into the antenna by an electric field. As the signal approaches the center of the antenna the current builds to a maximum at the center. Now the strongest magnetic field is created where the current is maximum as shown by Maxwell. Hence thinking of a 1/2 vertical as two 1/4 waves stacked, the current is maximum at the top part of the bottom half and the bottom part of the top half. Hence why I say it's very close spaced stacked verticals. Still there is some gain. There is a about .85 db increase from the "stacking". This lowers the radiation maximum to about 20 degrees. So with lower radiation maximum, more signal is receive or transmitted closer to the horizon where the signal from distance stations is also maximum. Though only .85 db gain (over a 1/4 wave vertical) it will appear one is doing better than that. This is because the antenna is then aligning with the maximum signal coming from the horizon. After that much typing I hope I kept to the point and answered my own question. :@)[/QUOTE]

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