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Re: [RFI] Am I hosed? RFI problems

To: Paul Christensen <w9ac@arrl.net>
Subject: Re: [RFI] Am I hosed? RFI problems
From: Kelly Johnson <n6kj.kelly@gmail.com>
Date: Mon, 16 Aug 2010 06:58:59 -0700
List-post: <rfi@contesting.com">mailto:rfi@contesting.com>
Do you really think I am that stupid?  Trust me, I know how to df and I DID use 
a portable radio to find this house. Been dfing for years and I'm good at it.  
I didn't just turn the beam that direction. I did my homework. I've been 
tracking and documenting for two weeks

Sent from my iPhone

On Aug 16, 2010, at 4:06 AM, "Paul Christensen" <w9ac@arrl.net> wrote:

> Kelly,
> 
> You'll need to start documenting the interference.  To the best of your 
> ability and time, keep a log of the times the interference starts and 
> stops -- even if its days in between.  As has been suggested here on 
> numerous occasions, first ensure that the interference is not coming from 
> your own property.  That involves turning off all panel breakers and 
> disconnecting battery-backed systems (e.g., security alarms).
> 
> It's unreasonable for the neighbors to be turning on/off power without 
> evidence.  You need to secure some minimal evidence before making contact 
> with them.  If you don't, you're only a boy crying "wolf!" at best.  At 
> worst, you've just become the new neighborhood crackpot.
> 
> The mind begins to conjure all kinds of things when the interference is 
> really bad.  "I need to move," "questionable renters," and "super powerful 
> computers" mean nothing when you really need to flesh-out the root cause of 
> interference.
> 
> Today, we're confronted with more sources of interference than ever before. 
> But fortunately we have some tools that were not available until recently. 
> It may take you some time, but if you want to get really proficient at noise 
> source detection, you're going to have to become knowledgeable with noise 
> patterns and select the right equipment for detection.
> 
> Before contacting neighbors, utility company or the FCC, you really need to 
> have your facts straight.  Simply turning your beam in the direction of the 
> perceived noise source isn't nearly enough.  You've got to localize it 
> through triangulation.
> 
> I have two systems here:
> 
> (1) The first is a hand-held 3-element 2m Yagi and a 2m HT capable of AM 
> mode.  This system is primarily used for broadbanded power line noise;
> 
> (2) The second system has been seeing much more use here in the past year, 
> primarily due to the increased proliferation of switch-mode appliances.  It 
> consists of an Elecraft K3, SDR-IQ with SpectraPlus software, netbook PC, 
> Palstar active rotatable loop antenna, and a small 12V gel-cell battery.  I 
> purchased a mid-size Pelican case to allow me to quickly set-up and break 
> down the equipment as I roam the neighborhood.  I generally do not need to 
> access the neighbor's property.  Most of my measurements are taken at the 
> street or from within my property.
> 
> After some time spent with switch-mode noise sources, I can now localize a 
> noise source in about 30 minutes to nearly pin-point accuracy.  However, 
> some noise begins in a room of the home, and the home wiring propagates the 
> noise to make it appear as if its coming from a different part of the house. 
> That's one reason why it's so important to move around and take quality 
> measurements.  My system is self-documenting.  I take PC screen captures of 
> SpectraPlus showing noise levels all pointing to a single location.  That 
> becomes my evidence for presentation to a neighbor, or if necessary to the 
> FCC.  When you've got that kind of powerful data, the FCC is really on your 
> side.  But you cannot go to the FCC and talk in terms of "questionable 
> neighbors," and "super powerful computers."
> 
> It may seem like this is all going over-the-top in equipment and procedure, 
> but if we want to enjoy the hobby without running a noise blanker all the 
> time, we all need to become proficient in recognizing noise source patterns 
> and know how and what type of equipment is needed to detect the problem with 
> a high degree of accuracy.
> 
> Paul, W9AC
> 
> ---- Original Message ----- 
> From: "Kelly Johnson" <n6kj.kelly@gmail.com>
> To: "RFI List" <rfi@contesting.com>; <mike@rfiservices.com>
> Sent: Sunday, August 15, 2010 10:19 PM
> Subject: [RFI] Am I hosed? RFI problems
> 
> 
>> It took me two weeks, but I'm now about 99% certain that I found the
>> source of my horrible RFI problem.  It's a house about 100 yards from
>> me.  A group of questionable renters just moved into that house a few
>> weeks ago.  The noise is worse than anything I have ever heard.  It's
>> S9/S9+ on 40m through 10m; dropping down to S7 or so on 6m (all while
>> I beam that direction, which is unfortunately the direction I must
>> beam for the East Coast from here in CA).  I can null it out if I beam
>> perpendicular to that direction, but unfortunately, there aren't that
>> many stations of interest directly north or south of me :-(
>> 
>> When I told the renter today that I have heard the noise start at 8am
>> the last 2 days, his first response was: "there's a guy here that has
>> a very, powerful computer that he turns on at 8am".  He asked the guy
>> to turn it off to see if it was the source and the guy clamed to have
>> done it, but I don't believe he did.  I think he was just trying to
>> get rid of me.  The noise was still there.  When I asked the guy if he
>> would be willing to shut everything off to see if it went away he said
>> no.  I don't know what to do now.  My HF station is nearly worthless
>> at this point with S9+ noise.  I can't hear much of anything above the
>> hash.  My S meter read S0 last night at 10:30pm and still S0 this
>> morning from 6am until 8am.  I was sitting in front of the radio at
>> 8am when the noise came on.  The S meter instantly jumped from S0 to
>> about S7.  It slowly got worse until it peaked at S8 on CW in a CW
>> 250HZ bandwidth and S9+ in a 2KHz bandwidth on SSB.
>> 
>> Any advice (other than move, wait for these guys to move, or something 
>> illegal)?
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> 
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