>The focus should be in the end of the waveduct (or whatever's the name of the rod). It's already manufactured as a good enough paraboloid - for any practical use, we can consider both the sunshine and the satellite signal to come as parallel rays (although they are not exactly parallel), so what works for one, should work for the other. I expect the plastic cap on the end of the waveduct should melt in a few seconds.

So, regardless of where and what angle the sun hits the surface, it is directed back to the rod?