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Jeff Liebermann Jeff Liebermann is offline
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Default Interference in FM radio reception.

On Sun, 08 Jan 2012 19:09:39 -0500, micky
wrote:

I have to say, this sounds like the opening scene from a murder
mystery. Only cars are big enough to start the lights.


Nope. They respond to people. I park there all the time. As I
vaguely recall, the motion sensors are located about half way up the
light poles. They take a few seconds to come on to full brightness,
and likewise, fade slowly when they turn off. Since the parking lot
lights are independently controlled, it's possible to have them come
on in sequence as one walks slowly across the lot.

The woman
parks the car, away from the entrance so other cars won't ding hers.
She walks to the store, is almost there, remembers sometihing in the
car and has to go back, and on her second trip to the store, the
parking lot lights go off, and she hears footsteps behind her. We
only see her legs and his legs, and soon they are both running.


Considering the time of day and the neighborhood, that's quite likely.
Fortunately, having the lights come on when the prospective car thief
enters the parking lot tends to provide a rather strong deterrent.

In the next scene, there are a lot of police standing around.


Possibly. The city police station is about 200 meters away.

The problem with finding sources of interference and such is the
hardware required. I used to do quite a bit of wi-fi sniffing,
searching for various sources of interference, leeches, hackers, DoS
sources, over-powered radios, and such. Same with searching for stuck
transmitters on commercial frequencies, foreign fishermen on US
frequencies, unlicensed operators, and premature LPFM stations. While
the equipment varies, it always seems to attract the attention of the
authorities. Walking through a busy shopping center parking lot, with
a fiberglass pole, topped with a small dish antenna, dragging a pile
of black boxes, with my face glued to a laptop. To the average
shopper, I was a cross between a terrorist and a visiting
intergalactic alien. No melodrama, but plenty of answering really
dumb questions. After a while, I learned to think first, and search
after. Have fun finding the interference source.

--
Jeff Liebermann
150 Felker St #D
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