Topband: Interference help

[D Rodman MD]

I made this video to help me identify a source and get some help with a 
carrier and broadband interference noted on the low bands.  I have 
identified two general signals.  They have a significant AC hum.  One is 
strongest to the West of my location and peaks at about 20dB over S9 On 
the meter.  It starts in the AM broadcast band and is heard up to about 
8.9MHz.  It is strongest about 3520kHz.  You can see it and hear the 
noise in the video posted on YouTube:

http://www.youtube.com/watch?v=chWUMQUBqlw&feature=c4-overview&list=UUA9lAJmr2N3s5BkA7XyLDGg

In the background, you see and hear a second carrier about S9 This runs 
through the 160m band and stops abruptly around 3.9MHz.  It is strongest 
to the East of me, based on the K9AY antenna.

I haven't yet put my spectrum analyzer on the antenna input but plan to 
do so.  The stronger signal starts daily around 7PM.  It is off by the 
time I wake up.  I am hearing this on two radios both with direct wire 
antenna into the radio and via a listening antenna with preamp 
operating.  I have been through my house with a battery operated SWL 
receiver tuned to this frequency.  I don't see a source inside my house. 
  I have cut all the breakers in the house sequentially and there was no 
drop in the signal.  I do have lots of fluorescent bulbs in the house 
but they can all be turned off with no difference of the signal.  As a 
matter of fact, I walked around the house with a flashlight after the 
entire house was darkened and could not find the source.  As I walk 
around the building with the radio, the signal is strongest around any 
of the refrigerators or devices with motors.  If I shrink down the 
antenna, I do not see any source within the house.  I even shut down the 
laptops and disconnected the power supplies with no benefit.

I really do not know what to do about this.  Does this sound familiar or 
similar to anyone?

-- 
David J Rodman MD
Assistant Clinical Professor
Department of Ophthalmology
SUNY/Buffalo

Office 716-857-8654