Topband: Low band noise

[Bruce]

Getting noise from my NW direction. Does not seem to be local. Started wondering what, at distance,  could be causing it. At times it seems to have a rhythm like a motor.

There are a lot of power generating wind mills showing up.  Checking through Google, they generate DC and convert to  3 phase AC it with an inverter. The frequency and phase of the inverter is controlled with a sample from the power grid. 

Could their inverters have enough sine wave distortion to have harmonic energy?

So my question is: Does anyone have first hand knowledge of interference on the low bands from  power generator wind mills? 

Bruce-K1FZ
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