Yep thats power line noise all right. Being out here in the Mojave Desert with high winds and land scattering sand and dust all the time, the lines and insulators get dirty and arc causing RFI all over the bands. Its all over the place and many times have to drive some what out of town to find a quiet place. I have called the power company many times and complained, and I even tell them what pole its coming from.
The latest noise is a pole about 150 feet from me, while listening to the noise in my 1977 luxury truck I slam the pole with a sledge hammer and the noise quits for a moment. I don't share that with the power company.
They have fixed about 5 noisy RFI problems in the local area. They showed up for the pole just across the street once, I came out and talked to them, There attitude was "go away son you bother me" but they fixed it so I cant complain I guess.
I bought a new Icom 7300 about 6 months ago, and it has a impressive noise cancelling functions Noise Blanker and ANL that works quit well. Looking into a some ferrites for the coax.....
Jay in the Great Mojave Desert