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The next thing to notice is it's the vertical dipole that feeds the horizontal loop and the horizontal dipole that feeds the vertical loop. If the dipoles radiated significant energy, the PDL might have less then 3 db isolation between vertical and horizontal since the dipole and quad would always be radiating in the opposite polarity. That is not the case since the dipole is delivering most of its energy to be radiated on the quad loop. However, we also have to consider there is most likely some small degree of radiation from the dipoles. That could make it a poor choice to add a Yagi element directly in front of a PDL driven element.

The Yagi is more likely to parasitically couple to the energy in the dipole of the driven element rather then the energy in the quad of the driven element. That energy is in the reverse polarity and also takes away some energy that would be driving the quad driven element to parasitically excite the wrong Yagi director. For a PDL-3 or even a 4, I would probably go all quad. Anything larger and I would make the reflector, driven and first director as quads and all other directors as Yagi's. That's because each director you add is excited by the element in front of it. As long as you have one quad director in front of the PDL driven element, any Yagi directors in front of it should only be parasitically coupling to the desired polarity.

Hi Shockway, thanks for sharing with us and yes i understand that its a folded 1/2 wave dipole.Im trying to make sense of you saying the vertical is feeding the horizontal dipole and visa - versa.Im looking in the pdl2 manual and fig 9 shows the vertical connector , the vertical gamma match feeding the vertical folded dipole. ??? . also thanks again for all your info , it sure helps the thread.

[/QUOTE]

<blockquote data-quote="sob" data-source="post: 374199" data-attributes="member: 25100">[The next thing to notice is it&#039;s the vertical dipole that feeds the horizontal loop and the horizontal dipole that feeds the vertical loop. If the dipoles radiated significant energy, the PDL might have less then 3 db isolation between vertical and horizontal since the dipole and quad would always be radiating in the opposite polarity. That is not the case since the dipole is delivering most of its energy to be radiated on the quad loop. However, we also have to consider there is most likely some small degree of radiation from the dipoles. That could make it a poor choice to add a Yagi element directly in front of a PDL driven element.The Yagi is more likely to parasitically couple to the energy in the dipole of the driven element rather then the energy in the quad of the driven element. That energy is in the reverse polarity and also takes away some energy that would be driving the quad driven element to parasitically excite the wrong Yagi director. For a PDL-3 or even a 4, I would probably go all quad. Anything larger and I would make the reflector, driven and first director as quads and all other directors as Yagi&#039;s. That&#039;s because each director you add is excited by the element in front of it. As long as you have one quad director in front of the PDL driven element, any Yagi directors in front of it should only be parasitically coupling to the desired polarity.</blockquote>Hi Shockway, thanks for sharing with us and yes i understand that its a folded 1/2 wave dipole.Im trying to make sense of you saying the vertical is feeding the horizontal dipole and visa - versa.Im looking in the pdl2 manual and fig 9 shows the vertical connector , the vertical gamma match feeding the vertical folded dipole. ??? . also thanks again for all your info , it sure helps the thread.[/QUOTE]

[QUOTE="sob, post: 374199, member: 25100"] [ The next thing to notice is it's the vertical dipole that feeds the horizontal loop and the horizontal dipole that feeds the vertical loop. If the dipoles radiated significant energy, the PDL might have less then 3 db isolation between vertical and horizontal since the dipole and quad would always be radiating in the opposite polarity. That is not the case since the dipole is delivering most of its energy to be radiated on the quad loop. However, we also have to consider there is most likely some small degree of radiation from the dipoles. That could make it a poor choice to add a Yagi element directly in front of a PDL driven element. The Yagi is more likely to parasitically couple to the energy in the dipole of the driven element rather then the energy in the quad of the driven element. That energy is in the reverse polarity and also takes away some energy that would be driving the quad driven element to parasitically excite the wrong Yagi director. For a PDL-3 or even a 4, I would probably go all quad. Anything larger and I would make the reflector, driven and first director as quads and all other directors as Yagi's. That's because each director you add is excited by the element in front of it. As long as you have one quad director in front of the PDL driven element, any Yagi directors in front of it should only be parasitically coupling to the desired polarity.[/QUOTE] Hi Shockway, thanks for sharing with us and yes i understand that its a folded 1/2 wave dipole.Im trying to make sense of you saying the vertical is feeding the horizontal dipole and visa - versa.Im looking in the pdl2 manual and fig 9 shows the vertical connector , the vertical gamma match feeding the vertical folded dipole. ??? . also thanks again for all your info , it sure helps the thread. [/QUOTE]

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