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Re: [RFI] My RFI battle....progress report.

To: <kgordon2006@frontier.com>
Subject: Re: [RFI] My RFI battle....progress report.
From: "Ed-K0iL" <eddieedwards@centurylink.net>
Reply-to: eddieedwards@centurylink.net
Date: Sun, 23 Mar 2014 21:25:56 -0500
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>

Here's some other good links and articles on power line noise on the ARRL
web page:


73, de ed -K0iL

-----Original Message-----
From: Kenneth G. Gordon [mailto:kgordon2006@frontier.com] 
Sent: Sunday, March 23, 2014 7:29 PM
To: Ed K0iL
Cc: Rfi@contesting.com
Subject: Re: [RFI] My RFI battle....progress report.

On 23 Mar 2014 at 13:45, Ed K0iL wrote:

> Ken,
> Based on your latest description, are you looking for narrow-banded 
> noise spikes?

> Or is it really very broad-banded--only being stronger at the resonant 
> frequencies of the antenna you're using?

Yes. Exactly, in fact.

> Power line noise is always very broad-banded getting weaker as you 
> tune higher in frequency

That is exactly what I am experiencing here

>--this is more obvious when using a broad-banded  log-periodic antenna 
>like I have at work.  Whereas the really strong,  narrow-banded, spiked 
>noises are usually generated by various in-home  devices like TV sets 
>and computers.

I have eliminated those from consideration: I connected the FT-890 to a
battery, and killed the house main breaker which turns off EVERYTHING in the

There was absolutely no change whatever in the noise. None. Zero. Nada.

Conclusion: it ain't in my home. :-)

> Also keep in mind when tracking power line noises, you will find RFI 
> sources everywhere,

Boy! Ain't that the truth!

> but not all of them, and probably only a few of them will cause RFI 
> noise to your ham antenna because of standing waves (peaks and nulls) 
> along the power lines.  The best way to determine if the noise you 
> tracked down is the same noise you are hearing at your ham shack is to 
> get a visual waveform reading on a scope.

Although I do have a portable 20 MHz dual-trace scope, I don't have it in
the shack at the moment. It is in storage. I am hoping I won't have to dig
it out. In the meantime, I am using Spectran and a laptop.

>  This waveforms method is recommended by Mike Martin, K3RFI, of RFI 
> Services, and is described in the book "AC Power Interference 
> Handbook" by Marv Loftness, KB7KK.  I'll attach a QST article that
describes this method.

Thank you. I'll read it immediately.

> Your power company should be using this waveforms method to track 
> power line noise and reduce the amount of RFI repairs they need to 
> make to meet the FCC's Part 15 requirements.  Why fix noises that do 
> not cause RFI to any licensed services?  (or at least have not 
> generated and complaints!)  This makes both the power company and the ham

Yes. I am in contact with a power company employee who also happens to be a
ham, and is also in charge ot taking care of RFI complaints. If things go
well, I may see him next week.

> Good hunting and GL! 

Thank you, Ed.

vy 73,


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