<Does the searcher have an open mind?>
Ed,
Having the equipment (now) I take every opportunity to 'run to ground' these
noise sources that crop up in my environment. I have never contacted the ARRL.
This includes (this past year) 1) a multiplicity of 'wandering carriers' on 160
and 80 meters that were DF'd to three different residential addresses in the
City of Allen at distances of just under a mile to over a mile away 2) four
different power line noise sources three of which have been corrected by the
power company. 3) a new neighbor has moved in next door, and several noise
sources sporadically have begun appearing. I have taken pains to perform
surveys up and down the street and out to the periphery of my small lot. All
indications are the house next door is the source. This last issue remains open
at present.
Begin speculation.
I think, but am not certain, that the wandering carriers are associated with
wireless dog fences. I first took notice of one of them on 80 meters in
December 2013. This year such a carrier appeared on 160 meters and I DF'd it
(and a third carrier) to separate addresses in widely different directions.
End speculation.
What seems to have kicked off this series of e-mails was a request I made to
Tom for factual information regarding the location's environment and also the
antenna type used in a video recording. Speculation comes later. based on more
factuak information (hopefully).
I might add, I have found it quite advantageous to do DF via bicycle,
especially on power line RFI where travel via car is impractical such as up and
down a sidewalk adjacent to a busy one-way thoroughfare. Localization of RFI
to an individual power pole is a discussion we can have at a later time.
Regards,
Jim WB5WPA
From: "Hare, Ed W1RFI" <w1rfi@arrl.org>
To: "rfi@contesting.com" <rfi@contesting.com>
Sent: Monday, September 26, 2016 2:29 AM
Subject: Re: [RFI] Noise - where do I start?
<Does the searcher have an open mind?>
I can't begin to say how important this is.
ARRL staff hear all the time from hams about utility "investigations" in which
the utility investigator did not set out to find the noise plaguing the ham,
but begins the investigation with a goal of proving that the noise is not
coming from utility equipment. The investigator then finds a noise in a house
a mile away and then concludes that the noise the ham hears is coming from that
house, so the investigation is over.
We also hear from hams who before calling us have made up their minds that the
noise they are hearing must be power-line noise, and so are not open-minded
even about the process of beginning their investigation by turning off the
power to their own house. We literally do have a case that involved years of
working with the utility, only to find out in the end that the ham's noise was
caused by a battery charger plugged in to an outlet in his own garage, long
forgotten and running all that time. Others are convinced that their noise is
a "this" or a "that" and are barely able to consider any other possibility.
Ed Hare, W1RFI
________________________________________
From: RFI [rfi-bounces@contesting.com] on behalf of Frank N. Haas KB4T
[utility.rfi.pro@gmail.com]
Sent: Sunday, September 25, 2016 10:17 PM
To: rfi@contesting.com
Subject: Re: [RFI] Noise - where do I start?
Questions of greater importance:
1. Is the affected party equipped to do a search that will produce useful
results? A battery operated AM-FM-SW-VHF receiver with a useful signal
strength indicator and a directional antenna suitable for a walking search
that heats fairly well at the highest relevant frequency is essential. (My
personal choice is the Radar Engineers collection but for hams I recommend
the Tecsun PL660SLV available from Amazon or eBay for $85 to $150.)
2. Does the searcher have an open mind? This kind of search is not an
eyeball search until the structure containing the source is located...and
even then, equipment must still be relied upon to pinpoint the source. By
open mind, I mean a willingness to trust the equipment and not waste time
guessing or deviating from the search path to pursue something seen or
guessed.
3. Does the searcher know how to direction-find? The type of power
distribution facilities in the area is irrelevant at this point. Finding
the structure that contains the source is the only objective. Only by
trusting your equipment and using it correctly to lead you to the source
will the job get done with a minimum of wasted time and effort.
4. Has the searcher done enough listening and record keeping to have a
good idea when the source is active, the best (highest?) frequency at which
to listen to hear and track the source and decide what tools are best to
locate the source? (Receiver, antenna, attenuator)
I do this for a living so for me time is money. Everything I do is done for
a good reason or I'm wasting time and money. Efficiency demands that every
part of the process have a useful purpose.
Hams and enthusiasts use these situations as learning experiences so extra
steps and experiments are often included. Lessons learned and experience
gained justify such steps. I still think that every step should be
evaluated to determine the value it will add to the process. At each point
along the way, the question that should be asked is, "How will this help me
pinpoint the source?" If a good answer can't be found, abandon that step or
option and move on to what will help.
Hunting interference need not be complicated. In fact it's a pretty simple
process. One located it can be complicated to correct or eliminate but
that's another subject entirely.
Stepping off my soapbox now.
73,
FranK N Haas KB4T
Utility Interference Investigator
Florida (on vacation in NC)
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