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Just because you see some directional characteristics and a good SWR does not mean the antenna is working well. As has been already said any directional effect is due to shielding from the dish and has nothing to do with the dish acting like a parabolic reflector that would add forward gain. The dish is about 100 times too small. But more important is the orientation of the driven element (4 foot whip) with respect to the dish. First of all for the dish to be able to reflect energy back onto the driven element, the driven element should be parallel to the dish, not perpendicular. Second the driven element must be properly spaced out in front of the dish so that it's placed in the focal point of the dish. Not with it's feedpoint on the dish.

I won't argue that it doesn't work, it just doesn't work well and the dish is doing little more then acting like an insufficient ground plane. The signal would also be horizontally polarized and tend to talk broadside of the driven element. It could have some rejection on the back because it's not a balanced dipole and the ground plane would shield some signal from the back. Whatever signal you could produce with this dish would easily be surpassed by even the cheapest base ground plane. It's a 4 foot loaded 1/4 wave ground plane with a ground plane that's too small. That places it more then 2 db behind a simple half wave. That's not even including the major loss in cross polarization. This could be as much as a 20 db loss!

<blockquote data-quote="Shockwave" data-source="post: 196577" data-attributes="member: 10882">Just because you see some directional characteristics and a good SWR does not mean the antenna is working well. As has been already said any directional effect is due to shielding from the dish and has nothing to do with the dish acting like a parabolic reflector that would add forward gain. The dish is about 100 times too small. But more important is the orientation of the driven element (4 foot whip) with respect to the dish. First of all for the dish to be able to reflect energy back onto the driven element, the driven element should be parallel to the dish, not perpendicular. Second the driven element must be properly spaced out in front of the dish so that it&#039;s placed in the focal point of the dish. Not with it&#039;s feedpoint on the dish.I won&#039;t argue that it doesn&#039;t work, it just doesn&#039;t work well and the dish is doing little more then acting like an insufficient ground plane. The signal would also be horizontally polarized and tend to talk broadside of the driven element. It could have some rejection on the back because it&#039;s not a balanced dipole and the ground plane would shield some signal from the back. Whatever signal you could produce with this dish would easily be surpassed by even the cheapest base ground plane. It&#039;s a 4 foot loaded 1/4 wave ground plane with a ground plane that&#039;s too small. That places it more then 2 db behind a simple half wave. That&#039;s not even including the major loss in cross polarization. This could be as much as a 20 db loss!</blockquote>

[QUOTE="Shockwave, post: 196577, member: 10882"] Just because you see some directional characteristics and a good SWR does not mean the antenna is working well. As has been already said any directional effect is due to shielding from the dish and has nothing to do with the dish acting like a parabolic reflector that would add forward gain. The dish is about 100 times too small. But more important is the orientation of the driven element (4 foot whip) with respect to the dish. First of all for the dish to be able to reflect energy back onto the driven element, the driven element should be parallel to the dish, not perpendicular. Second the driven element must be properly spaced out in front of the dish so that it's placed in the focal point of the dish. Not with it's feedpoint on the dish. I won't argue that it doesn't work, it just doesn't work well and the dish is doing little more then acting like an insufficient ground plane. The signal would also be horizontally polarized and tend to talk broadside of the driven element. It could have some rejection on the back because it's not a balanced dipole and the ground plane would shield some signal from the back. Whatever signal you could produce with this dish would easily be surpassed by even the cheapest base ground plane. It's a 4 foot loaded 1/4 wave ground plane with a ground plane that's too small. That places it more then 2 db behind a simple half wave. That's not even including the major loss in cross polarization. This could be as much as a 20 db loss! [/QUOTE]

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