[RFI] AC line noise

[n6cw@aol.com]

Hi All,
 
In my quest to eliminate RFI in my Qth, I have also been working on some AC line noise problems. This is mostly an annoyance to my XYL who listens to AM radio on our stereo set that has a constant hum in the radio, 24/7. I have tracked the noise to both my AC power meter and a light pole across the street. I have underground power lines. I can take the portable and follow the noise, with the radio 6 inches off the ground from the AC meter, to a junction box at the street (which supposedly has the cable TV cable only), and across the street to the light pole. There are a couple of ground mounted power transformers (?) on either side of the light pole but they do not seem to be radiating any noise. This noise does not normally bother my amateur radio receiving capabilities, but I am thinking it might be the source of some flareups that do bother me. Turning off the mains of my house does not reduce the noise. The radio that is being bothered is directly on the wall on the other
  side of the AC meter. And I can take the portable anywhere on the AC meter side of the house and get the noise.
 
My question is, should I be getting this kind of noise using a portable radio within 1-2 feet of the AC meter or the power pole. Would this be normal? Should there be any kind of line noise in this situation? I know I can move the stereo system to the other side of the house and eliminate the problem but it is perfect where it is. 
 
Terry Baxter/N6CW