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Originally Posted by elgemcdlf
If mesh were a solid to microwave then hole diameter would not matter
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Unless you're buying a 20 year old mesh dish, hole diameter really isn't much of an issue. Any recently made dish has a small enough spacing that there is very little loss. I just went out and measured the mesh size in my two mesh dishes,{about 4mm spacing and 2mm diameter) and used a nomagraph which calculates gain loss due to signal getting through the mesh. I may well have made some measurement and calculation errors, and welcome corrections, but I came up with about a 2% loss. I'd suggest that there is much more loss due to non parabolic (or eliptical as was suggested to me in another forum) shape of the dish, regardless of the material. My mirror experiments is enough to convince me of that. Basically, the wavelength of KU is about 12 times the size of the holes in the mesh.
Solid dishes CAN be more stable relative to shape and CAN be more perfect in shape, but at a high expense for big dishes, and stability means little if it's not shaped right in the first place. Plus, for a big dish, solid means weight and means low velocity wind problems (at high wind speeds a mesh dish is just as bad as a solid dish), both of which means a more sturdy mount is requirred, meaning even more expense. I still say that I'll live with the 2% signal loss, and save enough money on the dish to buy a bunch of receivers.
I think the reason you don't see
Sadoun selling 3' mesh dishes, is that for small dishes I'd guess that it is probably cheaper to construct a solid dish, since it is just a single stamping operation rather than constructing a grid and placing a mesh on it, but for big dishes it's cheaper to construct a mesh dish for several reasons.
One thing is pretty certain, and that is, given a good quality mesh dish and a good quality solid dish, there will be little if any difference with respect to what channels anyone on this forum will ever receive.