[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: Off topic - power line



By far, most power-line noise is caused by corona.  Corona is
a partial discharge to the air which rarely occurs below 3 or
4 KV.   Corona produces an extremely wide-band noise, from
audible up through HF, VHF, UHF, and into the microwaves,
often peaking around 40-70 MHz.  Back in the 1950s and 1960s
it was almost impossible to operate 6M AM mobile because of
ignition noise and corona, and even though ignition noise
has been pretty much eliminated today, corona noise is worse
than ever.

Corona produces ozone (the gas you can smell after a thunder
storm) and even produces a visual display under favorable
conditions.  The high voltage ionizes the air, usually
concentrating around a sharp point or edge.  In my experience,
most power-line corona is caused by poor maintenance by the
utility company.  Dirt and other contaminants build up on the
porcelean insulators.  This rough surface breeds a corona
discharge.   Utility companies are required by law to fix
these problems, so as to not interfere with radio communications,
but many don't do a very good job.  Eventually, this catches up
with them, as unchecked corona will eventually cause erosion
of insulating materials and cause an electrical failure.  Many
utility companies do not even have the test equipment or trained
technicians to track down and fix corona-related problems.  Some
have bought the equipment, but don't have anyone who knows how
to use it- and don't care much.

Recent laws to control corona discharges put the utilities in the
position of having to fix the problems or face stiff fines. My
advice is to complain to your utility company if you are experiencing
noise which is harming your ability to receive radio signals.  You
will likely be ignored on your first few calls, but be persistant.
You may have to resort to threats that you will file complaints
with the FCC.  You may be able to get in touch with someone in thier
legal department, who might even be aware of the new regulations and
light a fire under someone to fix the problem before being slapped
with a stiff fine.  There is no excuse for a power distribution
company to allow thier overhead distribution system to get in such
poor shape as to cause an S9 noise on your receiver.  Raise hell, and
make them aware of this worldwide problem.   73 John  W5EME
-----------------------------------------------------------------
Michael P. Olbrisch wrote:
> 
> There are so many different things that can-do-will cause electrical
> noise.  The most important thing you need to know is how responsive
> is the company to complaints?  If they are quick, do a good job, and
> are responsive to your needs, no problem.
> 
> Some of the things that cause noise are:
> loose connections
> dirty insulators
> animals on poles
> tree limbs in wires
> rain
> dust
> unfiltered appliances nearby
> 
> Rarely are the noises caused by generation, although bad brushes in
> the DC exciter -could- cause some problems.  I work in a power plant,
> and I listen to AM talk radio all day long.  But then again, we are
> very careful to keep everything right here.  Also, the frequency you
> operate will determine how susceptible your station is to noise.  I
> would not like to listen to WWV on 60 kHz, but a 440 MHz repeater
> shouldn't be a problem.  Your mileage may vary.
> 
> Good luck.
> 
> Mike.
> 
> Vy73,  Mike.   KD9KC    MARS: AAV6EV
> kd9kc@elp.rr.com  -  kd9kc@amsat.org
> Home page: http://www.qsl.net/kd9kc/
> The farthest WEST ham in West Texas.
> 
> We must ban all guns because a lunatic may kill dozens of innocent people
> with one.  But if you want to carry a gun to protect yourself from such a
> lunatic you are paranoid idiot.
> 
> Police operate in pairs and with backup.  This is why they need magazines
> that hold more ammunition.  You must face criminals alone and without
> backup.  Therefore, you need less ammunition.
> 
> > > -----Original Message-----
> > > From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On
> > > Behalf Of Francisco Costa
> > > Sent: Thursday, August 24, 2000 2:21 PM
> > > To: amsat-bb@AMSAT.Org
> > > Subject: [amsat-bb] Off topic - power line
> > >
> > >
> > > Hello my friends
> > >
> > > Sorry the off topic email, but I need your help.  The story is: last
> year
> > > I bougth a piece of land to built my future house.  Since then I have
> > > been working on the necessary paper work, and now, when I was about
> > > to start building, I had an unpleasant surprise: the electricity company
> > > is installing a new aerial high voltage line (15 kV) very close to my
> future
> > shack (about 4m).
> 
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home