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Re: [RFI] Investigating receive noise - got a few questions

To: "Hare, Ed W1RFI" <w1rfi@arrl.org>
Subject: Re: [RFI] Investigating receive noise - got a few questions
From: David Eckhardt <davearea51a@gmail.com>
Date: Mon, 12 Nov 2018 23:26:22 +0000
List-post: <mailto:rfi@contesting.com>
Yes, Ed, we've seen plenty on the Justice Channel!  Even the neighborhood
was right for a large grow operation. The interference has not come back to
this day.

Dave - WØLEV

On Mon, Nov 12, 2018 at 10:36 PM Hare, Ed W1RFI <w1rfi@arrl.org> wrote:

> Depending on the grower, you'd either get them to shut it down, or shoot
> at you.
>
> What is legal on the state level is still not legal on the federal level
> and when it comes to enforcement, the current administration is not a
> likely bet to look away from a large-scale illegal growing operation.
>
> The growers aren't as afraid of the cops as they are afraid of rippers.
> For some types of indoor gardening, the crop could be very valuable and
> there are people who would enter that home to just take it.
>
> Ed, W1RFI
>
>
> -----Original Message-----
> From: RFI <rfi-bounces@contesting.com> On Behalf Of David Eckhardt
> Sent: Saturday, November 10, 2018 8:25 PM
> To: Dave <dave@nk7z.net>
> Cc: Rfi List <rfi@contesting.com>
> Subject: Re: [RFI] Investigating receive noise - got a few questions
>
> We had an interesting instance in Loveland, Colorado:  Lots of
> interference typical of a grow operation. We went to the neighborhood with
> receiver and a small loop coupled to an AirSpy SDR.  About 20-minutes into
> sleuthing, the interference want away, never to return. I believe someone
> running a grow operation (pot is also legal in Colorado) saw us and shut it
> down.
> Also afraid of being caught, so its never reappeared.   Didn't have to do
> anything other than show up with proper equipment.
>
> Dave - WØLEV
>
> On Sun, Nov 11, 2018 at 1:16 AM Dave Cole (NK7Z) <dave@nk7z.net> wrote:
>
> > Hi Andy,
> >
> > If you can, build a loop, and DF the source.  Use the null to pin down
> > the direction.  That will help a lot.  Triangulate on it, and that
> > will get you close.  Once close, see if you can hear the RFI on a VHF
> > AM receiver.  If so, get a three element beam, and start hunting.
> >
> > Once you locate the source, you may want to contact the person living
> > there, in the kindest of ways, and ask if you can verify the RFI is
> > coming from his/her home.
> >
> > I always have a second ham with me when I contact an RFI source, but
> > in Oregon, where pot is legal, 80% of the RFI not caused in my own
> > shack, is related to grow lights, so I am cautions.
> >
> > 73s and thanks,
> > Dave (NK7Z/NNR0DC)
> > https://www.nk7z.net
> > ARRL Technical Specialist
> > ARRL Volunteer Examiner
> > ARRL OOC for Oregon
> >
> > On 11/10/18 1:57 PM, Andy KU7T wrote:
> > > Hi,
> > > I am trying to sort out receive noise issues with my Flex.
> > >
> > > I am not exactly sure how clean the spectrum could/should be. I have
> > > the
> > feeling that I may be more concerned about this just because I can see
> > the spectrum.  I am in an residenial area with 5 acre lots, with miles
> > to the next town and businesses. I always throught/hoped I have no noise
> issues.
> > >
> > > I took some time last night to turn off all breakers, one after
> > > another,
> > until only the shack was left. Then I reduced everything in the shack
> > so the only thing left was the 12V power supply, radio, computer and
> monitor.
> > I also adjusted the noise offset on the Alinco Powersupply with no
> > changes, turned off the computer, and unplugged it. At this point any
> > wall warts, modems, routers, etc were also  off. Still no significant
> changes.
> > >
> > > Take a look here at my spectrum, recorded while I turned off a
> > > breaker
> > every 30 s. There is no difference between beginning and the end:
> > https://1drv.ms/v/s!AiAwh4TnZjYMhtoFCHwTeJdHO2MFGw
> > >
> > > I really have not found any major decreases in hash or noise.  Here
> > > are
> > my questions:
> > >
> > >    1.  Do I go right about this at all?  Should I only look at the
> > > ham
> > bands instead of looking at the half the HF spectrum?
> > >    2.  There is quite some pulsing/jumping of noise going on below
> > > 10
> > Mhz (see in video’s top spectrum). Are those normal static atmospheric
> > crashes or something else outside I should be investigating further
> > and if so how?
> > >    3.  There are patterns around 4 – 5 Mhz that are definitely some
> > patterns from some device. Is it worth worrying about these,
> > considering there are not near any ham bands of interest? Goes back to
> question 1 also:
> > do I care whats outside of ham bands?
> > >    4.  I have some harmonics, some spikes between 12 and 15 Mhz. the
> > distance between the spikes is about 17.6khz. Any ideas what that could
> be?
> > Is likely not in my house though…
> > >
> > > Any tips and ideas how to proceed?
> > >
> > > 73
> > > Andy
> > > KU7T
> > >
> > > Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for
> > Windows 10
> > >
> > > _______________________________________________
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> > > RFI@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/rfi
> > >
> > _______________________________________________
> > RFI mailing list
> > RFI@contesting.com
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> >
>
>
> --
>
> *Dave - WØLEV*
> *Just Let Darwin Work*
> *Just Think*
> _______________________________________________
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>


-- 

*Dave - WØLEV*
*Just Let Darwin Work*
*Just Think*
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