Nearby Power Lines

[Jonathan.Williams]

At one point, I had the opportunity to do some work on broadband over power line system measurements, and power line noise was a pretty big factor even up into the HF/VHF range. For E-field, at lower voltages (the MV lines you see in residential areas), bad insulators can produce all sorts of nonlinear effects (there's a certain type, widely used, that's particularly notorious for this and responsible for a lot of the ambient power line noise). But even at higher voltages, insulators can go bad. You'll never know until you try.