[RFI] Power Line RFI in Corn Country

[Dale Svetanoff]

All,

New Years wishes to everyone.  I decided to get my new year off on a good start - or, so I hope!   Today, 15 January, I contacted Alliant Energy, my electric power provider, about severe RFI that has existed at or near my location for most of 2009.  (Yes, I should have done something about it months ago, but that elusive round-to-it could not be found.)  The bands most affected are 160, 75, and 40 meters.  I have determined that the primary source of the wide bandwidth buzz saw is about 1 mile from my shack, in an ESE direction.  A few rides in my truck with the AM radio tuned to the local station, 600 kHz WMT, found the hottest point.  WMT, with 5 kW about 15 miles away, is totally inaudible under the racket when driving by one particular cluster of power poles.

I made my call at about 2 PM local time.  At about 3:30 PM, local time, I had a call from a line engineer who said he had been to my house and was now parked under the power lines I had described to the very pleasant lady who took my call.  He confirmed that WMT was wiped out on the BC radio in his truck, as well.  Further, he mentioned that they have had a few complaints from farmers in that area that they can not hear the farm reports on WMT due to the noise.

When I moved out here 9 years ago, residual noise on 75 and 40 was about S0 to S3, max.  The noise level would go up to about S6 or S7 in the fall when the grain dryers are running (probably from their ignition systems).  There are dozens of grain dryers within a mile or so of my place.  In early 2009, the buzz saw started, intermittent at first, then got worse as the year went on.  The noise level on 160m is now S9+10, on 75m it is S7 to S9, and on 40m, about S3 to S7.  I can hear harmonics of this stuff up as high as 6m.  Today was a first step.  The engineer told me that he will call in for their special RFI tracking unit to see what can be found.  One problem: the area in which the noise is located has power lines from two separate utilities:  Alliant has the 12.5 kV lines for local distribution, and another company has the 34 kV lines for inter-area distribution.  If the noise is on the 34 kV lines, Alliant said that they will inform the other company and keep the ball rolling.  Hopefully, I will not have to chase down the other guys.

I am thrilled and amazed that Alliant had a crew on the problem barely more than an hour after I called.  The crew confirmed my suspicions and they understand that I am a licensed Amateur Radio op with a station (the engineer saw the tower farm at my house).  I have read about many fiascoes with power companies on the reflector, so I thought I'd post my experiences to see if my luck is any better or different.  I know that many, if not most, power companies do cooperate in RFI issues.  I won't bore you with a blog, but I'll update the list (or even ask questions) as the process evolves.  Hopefully, someone else can benefit from the info.

Note:  The lady who took my info said that I provided much more and better details than they usually get.  For the record, I gave her my specific location, the road intersection where I found max noise, the call letters and frequency of the local AM station, and a description on the sound and what has been happening (including the fact that the whole mess may clear up for several minutes to an hour at a time).  I also gave her the specific frequency bands that have been most affected.  

73, Dale
WA9ENA