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Re: [TowerTalk] How far does RFI travel?

To: Mike Fahmie <wa6zty@yahoo.com>
Subject: Re: [TowerTalk] How far does RFI travel?
From: Ray Benny <rayn6vr@cableone.net>
Date: Mon, 9 May 2016 14:22:49 -0400 (EDT)
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Thanks for the good replies and suggestions.

As recommended, first thing for me to do is establish a noise background 
reference for my station. This would include readings at different times of 
day/night, different frequencies and directions, make noise recordings, etc. 

One thing, I am fortunate that all utilities are underground including the new 
sub-division. There is an overhead power line about a mile away that did 
generate some noise. I located the source, and luckily our local power company 
responded and cleared it up.

As far as private pot growers, I don't think I have noise from them. Arizona 
has legalized the commercial growing of medical pot, so we now have five such 
commercial farms in our little town, the nearest being about 3 miles away. 

I will look at some of the software suggests and see what works for me.

Thanks to all,

Ray,
N6VR

----- Original Message -----
From: Mike Fahmie via TowerTalk <towertalk@contesting.com>
To: jimlux <jimlux@earthlink.net>, towertalk@contesting.com
Sent: Mon, 09 May 2016 13:14:06 -0400 (EDT)
Subject: Re: [TowerTalk] How far does RFI travel?

Long ago, I was asked by a police officer friend to carry my portable HF 
receiver by a building that they believed housed a stolen mini-computer.  They 
hoped that the character/rhythm of the RFI would match that of another 
identical machine running the same OS.  I did, but did not hear the noise they 
were hoping for.
They were both disappointed and relieved since the next hurdle would have been 
to establish the validity of the search since they didn't have enough PC 
(probable cause) to obtain a warrant.  This was back in the days when, in 
California, warrant-less searches utilizing sensors more sensitive than human 
senses (ie, drug sniffing dogs) were at risk of being thrown out of court.-Mike-

 
      From: jimlux <jimlux@earthlink.net>
 To: Grant Saviers <grants2@pacbell.net>; Ray Benny <rayn6vr@cableone.net>; 
rfi@contesting.com; towertalk@contesting.com 
 Sent: Monday, May 9, 2016 9:43 AM
 Subject: Re: [TowerTalk] [Bulk] How far does RFI travel?
   
They are plenty interested in busting grow operations. It's more about whether 
RFI is probable cause for a search warrant.  It is not.  You could get the FCC 
to send them a letter, maybe, but RFI is not a state law issue ( i think its 
good thing that federal law preempts state and local for RF)



Sent via the Samsung Galaxy S®6 active, an AT&T 4G LTE smartphone-------- 
Original message --------From: Grant Saviers <grants2@pacbell.net> Date: 
5/9/2016  7:32 AM  (GMT-08:00) To: Ray Benny <rayn6vr@cableone.net>, 
rfi@contesting.com,     towertalk@contesting.com Subject: Re: [TowerTalk] 
[Bulk]  How far does RFI travel? 
One thing I noticed when driving around with a PC+ USB spectrum analyzer 
to find a new QTH, was how much quieter neighborhoods with in ground 
utilities were from those with the old "poles and pigs" distribution 
systems.  Another observation was that big HV transmission systems were 
quieter than expected when a few hundred yards from them.  My conclusion 
is the buried systems shield and choke the rf, just as happens with 
buried coax.   IMO, much of the rf trash we hear is generated by bad 
devices and then radiated from pole systems.  60 acres NW of me were 
recently developed, 20 homes on 2 acre lots plus open space and 
underground utilities and so far so good.  A plasma TV SW from me is an 
S4 problem, but I haven't tracked it down.  Hopefully, the new 
subdivison near you will be all buried.

Several local hams here are seriously affected S9+ all bands by large 
grow lights for recreational substances that are clearly not FCC 
compliant re radiated and conducted emissions.  The distance can be 
significant - 1/4 mile or more.  Most are probably illegal but of no 
interest to law enforcement given trends of the new laws.  The FCC 
either "doesn't have the resources" or "won't investigate where illegal 
activity may be happening without law enforcement present". A perfect 
Catch22.  In the past, when growing was clearly illegal, law enforcement 
used AM radios to find the grow sites.

Grant KZ1W
Redmond, WA

On 5/9/2016 0:21 AM, Ray Benny wrote:
>   body {height: 100%; color:#000000; font-size:12pt; font-family:arial, 
>helvetica, sans-serif;}This may seem a strange question to ask and there maybe 
>many answers, so I will try to be specific as to what I am looking for.
> A new subdivision is being built about 1/4 mile away, east and north east, 
> towards EU. The homes are custom build on 1 acre parcels. What I am trying to 
> find out: can I expect my noise level to go up as more homes are built?
> I spend a lot of time on 160m. I have a RX 4SQ and 2 wire beverage, and I do 
> hear a number of small RFI noises in a number of directions from nearby homes 
> in my rural area. Most of the time they do not cause any long term problems. 
> My thought is that when new housing comes in, new and more electronic gadgets 
> will be inside that can generate more RFI.
> I have done some RFI tracking, mostly electric fences and leaking/defective 
> power line hardware, but these sources are usually very distinctive and 
> usually easy to fine. Finding wall wart, LED, etc RFI is harder to find, 
> especially on someone else's property. Another way to ask my questions: "Does 
> this type of RFI noise typically radiate more than several hundred feet"?
> Any thoughts or experiences are welcome.
> Tnx & 73,
> Ray, N6VR
> Chino Valley, AZ
>

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-- 
Ray,
N6VR
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