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Dish Feed

C2

Sr. Member
Aug 3, 2005
2,408
82
158
I might need some help with my 23 cm band, 10-foot dish feed.

First, I replaced the C-band feed with a bi-quad antenna (bow-tie) with a 1/4 inch screen being used as its reflector. I also made the reflector with lips!

Q: Is that screen too large for a reflector?

I also looked at making a patch feed, but they are all circular polarized, and I want vertical polarization.

Q: any better ideas for a feed?

Then, I pur the reflector right about where the polarizer was with the C-band feed, assuming that would be the focal point, or just in front of that. I'm thinking that the feed might not be optimally placed. I will be using the formula: f = D^2/16d to determine the focal point of my dish.

Q: Do I place the bi-quad feed just in front of the focal point? I assume that it should be placed such that a reflection of the radiator on the other side of the reflector is placed just at the focal point. I mean that if the radiator is 1 inch in front of the reflector, then the focal point should be 1 inch in front of the focal point of the dish.

I spent most of the weekend trying to tune the dish and hit that ATV repeater, but nothing. So either 1) I cannot see the repeater and there is a building in the way, or 2) my dish setup is no good.

I need to find the exact point of the r
 

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