[CQ-Contest] RFI Issue

Joe Stepansky kq3f at comcast.net
Sun Aug 28 13:11:31 EDT 2005

I hope the group doesn't mind me taking a little bandwidth on this, but 
I've been searching for a solution to an RFI for months to no avail.  If 
anyone knows what this might be, or has seen this before, I'll be in your 
eternal debt.  It's my luck that this is roughly in the direction of Europe.

Since about April I've had RFI issues on 20 through 10 meters, but loudest 
on 15.  I have an IC756PROII, and on the scope it appears to be a series of 
spikes moving right to left (seems to be a switching power 
supply?...unstable and decreasing frequency).  When it's just the spikes 
the noise has a grinding sound on SSB.  But there's another 
component.  This is a series of little blobs moving very quickly left to 
right on the scope, which I take to mean unstable and increasing 
frequency).  This is accompanied by a rushing water sound (best I can 
describe it).

Here's another kicker....it NEVER occurs during rain.  Never.  The local 
power company has now been out four times trying to find this thing and 
have tightened the hardware on a number of poles, but the noise 
persists.  I'm convinced it's not the power company.

To give you an example of the sequence, today is a good example.  It rained 
last night/this morning, no noise.  Then the sun came out about 11 AM, the 
little spikes appeared, moving right to left on the scope.  The the little 
blobs appear.  This goes on for about an hour, then it's only the spikes 
and then the noise (and spikes) abruptly stops.  Then, the little spikes 
(and grinding noise) appear sporadically for maybe 2-3 seconds at a time.

I've never seen the noise appear at night,  And though it never appears 
when it's raining or damp, it's not there all the time when the sun's out, 

I've pegged the direction at 60 degrees, and have drawn a line with that 
heading from my QTH on the map I use for APRS.  I've driven that way a 
number of times, but nothing.  I've often come home to find the noise gone, 
so it's possible I was chasing a ghost.  Oh, I've shut off breakers in my 
house and it doesn't matter (besides the house is not at 60 degrees, but 
who knows?)

My wife was all set to drive me around this afternoon when the noise, once 
again, stopped.

Does anyone have a clue what this might be?  If you got this far, thanks 
for reading.

73, Joe KQ3F

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