Date: Tue, 10 Jan 2017 07:19:03 -0800
From: jimlux <jimlux@earthlink.net>
To: towertalk@contesting.com
Subject: Re: [TowerTalk] noise profiles...
HF noise related, so I guess it's on topic, although maybe this might be
better for the RFI list...
I was looking into the idea of using a RFI detection system on a UAV for
scanning neighborhoods for hot spots...
Law enforcement doesn't use RFI detection as a way to detect grow
operations - they *might* use it after having a warrant, but if they
have a warrant, an easier way is to look at the power consumption on an
hour by hour basis, which in most places these days they can do with a
simple request to the utility.
In the United States, it's not really legal to just do broad band
spectrum surveys for the purposes of detecting illegal activity. The
FCC, in its spectrum management role, can do such surveys to locate and
identify an RFI source, but in response to a complaint.
The basic rule is that law enforcement cannot use technical means that
are not "commonly available" (thermal imaging, radar, spectrum
analyzers) without a warrant. Obviously, there's a fair amount of
parsing what "commonly available" means - in the case of Kyllo, it was
thermal imaging used to detect the excess heat from the grow operation.
What is normal for a ham (a spectrum analyzer) would probably not pass
the "commonly available" test - it's the combination of sensor cost and
expertise in interpreting, etc. So as a result, LE isn't going to use
it - they're rather have a nice iron-clad bust than spend time arguing
exclusionary rule, etc.
For what it's worth, the power company does NOT look for this either,
and report to law enforcement - they only do it when asked, with a
warrant. The utility's point is that they have employees out in the
field who are exposed to potential bad guys, and they do not want their
service people being perceived as potential cops. Nope, they rather
have some clerk in a call center respond to the inquiry with a data file
of kW vs time and let LE make the decisions.
The utility will get involved if there's a "theft of service" - if you
have high consumption, and all of a sudden it goes to zero, then they're
thinking that someone might have bypassed the meter. That's a crime,
and the sudden drop is a reason to have someone go take a look (are
lights on, and there's no movement on the meter?). After that, then LE
can go get a warrant because there's probable cause to investigate for
electricity theft (and safety issues). And, if they go in and happen to
see a grow operation that's illegal (not all grow ops are illegal these
days.. maybe violating zoning or business licensing, but in many states,
it's legal to grow stuff).
## are u sure about the legalities ?? If you look at W0QEs site, he also
depicts a simple filter that goes on the 120 vac side, that will kill the
radiated noise from the grow lamps.
## They dont all use a 12 hr on, 12 hr off cycle either. That all depends on
which stage the plants are in. When small, they will use one type of grow
lamp,
and different on-off hrs vs when the plants are bigger, with different lamps
used, and
still different on –off cycles. I had this bozo move in behind me a few years
ago, and
2 months after he moves in, my line voltage was dropping like a rock, like
throwing
a light switch. lap top would dim a bit, fridge compressor would go wonky.
I measured
both sides of the line with a pair of fluke 87s. It would dim at 10 pm for 4
hrs, then back to
normal at 2am, then dim at 5-6 am....all over the map. In some grow ops, at
later stages, they
will have the lamps on 24-7..and move the lights on a track, to simulate the
sun moving from E-W,
then back again..from W-E.
## Funny thing was, we all have 200A service, the bozo behind me was on a
different 50 kva xfmr,
and we all have natural gas ovens, furnaces, hot water tanks, and fireplaces.
Some have natural gas
clothes dryers. This was in May, so not cold enough for any electric
heating....which nobody around here
even has....and not hot enough to turn on the Air conditioning. Power co
comes out and measures the load on the
xfmr...and its rock solid at 112 A. Of course this was at 5 PM..and voltages
were all normal. 3 hrs later, it
drops like a rock ! I gave up. Local ham said to listen to certain HF
freqs..and record the noise u hear.
The grow ops, for the most part, have a distinct sonic signature. Mine were
between the ham bands. Tuned to
em, they were stupid loud. 3 yrs later, swat team comes in,and mr grow op
gets busted. he was caught up in
a wire tap.
## cops are now twigged into tracking em down using SA + software + quasi
directional ants. They will also look for
heat signatures. All the power meters have been converted to smart meters.
Even if a meter is bypassed, or partially
bypassed, power co can see how much power from the xfmr...vs the sum total of
the 9 homes hanging from it. If the
maths dont add up, they investigate further. Most grow ops will bypass the
meter for some stuff, but the regular stuff
in the home is not bypassed. They still get a normal bill each month. A
huge portion of the grow op is not on the bill,since
its been bypassed.
## when the smart meters were initially installed, the contractor found
hundreds of homes, where the wires to do the bypass
were clearly seen, once the old analog meter was unplugged. Power company
policy is to guestimate how much power was
stolen. They take the guestimated value, then double that amount. Then bill
the grow-op for the portion ripped off x 2.
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