Topband: AM BCB noise in Portland, OR

[Tree]

Last night, I heard a very bad noise on the band.  It sounded like a bad 
connection somewhere that was mixing AM broadcast signals.  It was all 
over the band, but seemed worse around 1790 kHz.  It wasn't steady, but
breaking up - almost sounding like someone sending garbage CW.

This was similar to a noise I had heard a couple of years ago, but it 
went away after one night - before I could track it down.  I wanted to do
enough DFing last night to find out if it was something local on my 
property - or far away.

I got a bearing on it from my house (sort of west) which matched the 
beverage that heard the signal the best.  I found I could hear it on 
my car AM radio tuned to 1710 - so I started driving west.  The signal
stayed pretty constant in strength even going a mile or more - so it
was't something local to my QTH.

I do have a big AM station about 3 miles west of me (KXL - 20 KW at night)
and I drove over there and determined it was not that station.  From that 
QTH - I got a good bearing on the signal and it appeared to be from another 
big station that is about 10 miles from my QTH (KEX - 50 KW).  

I figure if it is coming from that far away - then it isn't something that
is totally parasitic.  It is probably also loud enough that other people 
can hear it.  

Of course - this morning as I was driving by there on my way to work, it 
was all quiet.  Hopefully, it will stay that way.

Tree N6TR/7