I agree that a power line won't "block" any signal, and a couple 120V lines won't be a problem, however if they are higher voltage, and/or if there is a transformer nearby, then they can present a problem, not by blocking the signal but via interference. My bud is right under a high voltage power line. {I often worry about what would happen if a tree pulled that line down onto my dish.} I think that line is at least 15,000V , maybe more. But right in line with one of the Canadian sats is the transformer, and I've always had problems with that slot, although it's been better since the newer more powerful sats took over. More recently, I put up my 90CM dish with the main intent of receiving AMC3 (for
PBS) and G26 (for preseason NFL). Well, I made the mistake of putting the darn dish exactly where that darn transformer was right in line with G26.
That's the one sat that I have problems with. I guess with the 90CM, it's possible that the transformer is actually blocking the signal, but I still think that it's mainly an interferrence problem coming from the high voltage transformer.
Usually though I agree. Power lines shouldn't be a problem.