[R-390] powerline noise

[Terry O'Laughlin]

My QTH has a horribly high noise level starting from what appears to be a 
raspy fundamental that wanders between 400 and 450 kHz.  It persists to 
well over 15MHz and has rendered all my shortwave radios essentially 
useless.  It even overwhelms my R-390, R-390A and R-388 on a medical 
isolation transformer circuit with a Kelvin ground.  My antenna ground 
system is extensive as well.

I tried tracking it down with my Sony 2010 and it seems to follow some of 
the power lines around the neighborhood.  But I can't pinpoint it.  I've 
been assuming for 2 years the source is the aluminum recycler (smelter) 2 
blocks away (the largest electrical user on the east side of town).  My 
Sony 2010 detects little or no noise around the factory and tons in a one 
block radius of my house.  I assumed it was the recycler because the noise 
is often much lower or gone on Sundays.

I let this go for a long time assume I couldn't get the Al recycler to deal 
with EMI.  Now that it appears to be coming from somewhere else I want to 
nail down and get somebody to fix it.

Any ideas?

73
Terry O'
WB9GVB