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Old March 21st 04, 07:09 PM
Rick
 
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Default Tracking down noise

I am trying to locate the source of power line noise in my
neighborhood. I drove around with a 10 meter am receiver with a base
loaded vertical on the car and found the noise source is hard to
pinpoint. Possibly this is because the noise is being conducted along
the power line? What is the best way to locate the source.
I am assuming if I can tell the power company that I am certain of the
pole (cracked insulator ?) that is causing the problem I stand a
better chance of getting action.
A related question - IF I was to find the pole where the noise
originates is there any chance of being able to actually see arcing
occurring?

Rick K2XT

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Old March 22nd 04, 12:29 AM
Mac
 
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Default

Hi, Maybe advisable to check your own house first, eg. computer controlled,
washing machine, dishwasher, stove, TV, video or dvd machine, or hot water
system etc. But I reckon the worst thing are the bedside "touch" lamps.
Good luck.

"Rick " wrote in message
...
I am trying to locate the source of power line noise in my
neighborhood. I drove around with a 10 meter am receiver with a base
loaded vertical on the car and found the noise source is hard to
pinpoint. Possibly this is because the noise is being conducted along
the power line? What is the best way to locate the source.
I am assuming if I can tell the power company that I am certain of the
pole (cracked insulator ?) that is causing the problem I stand a
better chance of getting action.
A related question - IF I was to find the pole where the noise
originates is there any chance of being able to actually see arcing
occurring?

Rick K2XT



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Old March 22nd 04, 01:53 AM
Crazy George
 
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Default

"Wes Stewart" wrote in message
Not really. Any decent power company will have an expert whose job it
is to find this stuff. Mine (a rural co-op) does not, although they
have tried very hard on several occasions. About the time I got their
guy sort of trained, he was injured and retired. Subsequently, they
called in the guy from the local metropolitan company with his
specially equipped van and he found the problems almost immediately.


Wes:

I have previously pointed out that few to none of the electric utilities
have noise experts any longer. Since deregulation, none of them want to try
to justify the cost to their stockholders, and the accountants are firmly in
charge. Ask Riley Hollingsworth or Ed Hare if you are reluctant to take my
word. I have worked as an independent in this field since well before
deregulation, and have watched the demise of the "noise expert". There are
still a number of them active as private consultants, and there is plenty of
work out here to keep all of us busy, but if there is still one employed by
a utility company, I would sure like to know his name and the name of the
utility, because I can no longer identify one from my lists.

Rick:

See:

http://www.arrl.org/tis/info/HTML/power_line_handbook/

on the ARRL web site for further guidance.

--
Crazy George
Remove N O and S P A M imbedded in return address




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Old March 22nd 04, 08:34 AM
Wes Stewart
 
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On Sun, 21 Mar 2004 18:53:49 -0600, "Crazy George"
wrote:

|"Wes Stewart" wrote in message
| Not really. Any decent power company will have an expert whose job it
| is to find this stuff. Mine (a rural co-op) does not, although they
| have tried very hard on several occasions. About the time I got their
| guy sort of trained, he was injured and retired. Subsequently, they
| called in the guy from the local metropolitan company with his
| specially equipped van and he found the problems almost immediately.
|
|Wes:
|
|I have previously pointed out that few to none of the electric utilities
|have noise experts any longer. Since deregulation, none of them want to try
|to justify the cost to their stockholders, and the accountants are firmly in
|charge. Ask Riley Hollingsworth or Ed Hare if you are reluctant to take my
|word. I have worked as an independent in this field since well before
|deregulation, and have watched the demise of the "noise expert". There are
|still a number of them active as private consultants, and there is plenty of
|work out here to keep all of us busy, but if there is still one employed by
|a utility company, I would sure like to know his name and the name of the
|utility, because I can no longer identify one from my lists.

It's been a couple of years but Tucson Electric Power was the one.
|
|Rick:
|
|See:
|
|http://www.arrl.org/tis/info/HTML/power_line_handbook/
|
|on the ARRL web site for further guidance.

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Old March 22nd 04, 02:12 PM
Rick
 
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Default

Thanks to all you guys for responding. Good info.
Here's a quick update.
I turned off the main breaker in my house and still have the noise.
As you experts point out, it is tough to get a bearing on the noise
with HF measurements. I tried on 20, 15, 10 with a 3 element yagi and
got peaks and nulls in different directions. Also with a 5 element 6
meter beam. Advice on the ARRL site said to use VHF, so as a first
cut I drove the neighborhood with my FT100 mobile rig, mode AM, and 2
meter 1/4 wave antenna. S meter is approximately S2 everywhere except
near two poles where it goes up to S7.
This is a rural area, heavily wooded, with houses set way back from
the street. Along the street there are many transformers on the
poles, with taps coming from the high voltage. Also there are these
approximately 1 foot long fuses. I know, because when the squirrels
get across my transformer that is the fuse that blows like a shotgun.
So there are many places where a bad connection could occur.

This morning I make my first call to the power company. I'm in
central NJ. Stay tuned.
And thanks again for the tremendous help and interest.

Rick K2XT

ps - I started this discussion on the antenna newsgroup because it
seemed most appropriate. I hope it's ok if we keep it here. I don't
crosspost.

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Old April 17th 04, 05:47 PM
zeno
 
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Walking around using an old RatShack portable short wave radio I was able
to track down an unusual noise source (an incessant clicking that was all
over 40-160m. I was able to aim the portable antenna at various wires
while walking around. This particular noise turned out to be someone's
bad telephone. When the telephone was disconnected, this loud
click-click-click disappeared. Seems like that bad telephone was somehow
"transmitting" this noise back through the phone lines.

Admittedly the noise from the power lines here are much more difficult to
pin down and seems to change with the weather. It can be very annoying
and discouraging. There is a high voltage transformer right here next to
the house, which means those hv lines are coming right down my driveway.
Designing an antenna which is not even close to parallel to these power
lines has helped somewhat. I am hoping the new 160m full wave loop which
will be further away is going to be a big improvement. I am just hoping
that the ladder line feed to this loop will not also pick up the noise.
If so I will have to change that feedline to coax which will be a
compromise.

Impoving my RF ground and making sure it was totally independent from the
A.C. safety ground at the house main has helped also. My primary RF
ground cable goes through a hole in the floor at the station and
immediately to a copper pipe driven in under the house. This first run is
shorter than 6'. This first copper pipe is then tied to several others at
about 10' apart to make up for the fact that they are only driven 5' into
the ground. Make sure your RF ground is independent of the house AC
safety ground. I also use a constant voltage transformer and a good power
conditioner because the AC here is a mess.

-bill

Rick wrote:

Thanks to all you guys for responding. Good info.
Here's a quick update.
I turned off the main breaker in my house and still have the noise.
As you experts point out, it is tough to get a bearing on the noise
with HF measurements. I tried on 20, 15, 10 with a 3 element yagi and
got peaks and nulls in different directions. Also with a 5 element 6
meter beam. Advice on the ARRL site said to use VHF, so as a first
cut I drove the neighborhood with my FT100 mobile rig, mode AM, and 2
meter 1/4 wave antenna. S meter is approximately S2 everywhere except
near two poles where it goes up to S7.
This is a rural area, heavily wooded, with houses set way back from
the street. Along the street there are many transformers on the
poles, with taps coming from the high voltage. Also there are these
approximately 1 foot long fuses. I know, because when the squirrels
get across my transformer that is the fuse that blows like a shotgun.
So there are many places where a bad connection could occur.

This morning I make my first call to the power company. I'm in
central NJ. Stay tuned.
And thanks again for the tremendous help and interest.

Rick K2XT

ps - I started this discussion on the antenna newsgroup because it
seemed most appropriate. I hope it's ok if we keep it here. I don't
crosspost.


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Old April 17th 04, 06:11 PM
Irv Finkleman
 
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Default

zeno wrote:

Walking around using an old RatShack portable short wave...


Impoving my RF ground and making sure it was totally independent from the
A.C. safety ground at the house main has helped also. My primary RF
ground cable goes through a hole in the floor at the station and
immediately to a copper pipe driven in under the house.


I did the same thing -- a 10 ft copper clad steel rod driven through a hole
in the concrete of my basement floor. The floor is about 5 feet below
ground level. I found out later that this was not a great idea because
the floor shields the ground below from moisture -- measuring the ground
rod to my waterpipe later showed a dc resistance of almost 50 ohms -- it
would have made a better dummy load. I have since put 4 10 foot copper
clad steel ground rods outside and bonded them together using silver
solder. This works much better.

A chum of mine, noting my problematic results, decided to go sideways
through his basement concrete intothe back yard where the soil would
be moist. The end result was partially flooding his basement after the first rain!
He wasn't home at the time!

I should note that the ground rods only provide the safety ground, however
they serve as the base for a number of other ground wires spread around
the yard in a sort of helter-skelter radial system. This provides a
pretty good RF ground.

Moral: The best intentions often have unintended consequences!

Irv VE6BP
--
--------------------------------------
Diagnosed Type II Diabetes March 5 2001
Beating it with diet and exercise!
297/215/210 (to be revised lower)
58"/43"(!)/44" (already lower too!)
--------------------------------------
Visit my HomePage at http://members.shaw.ca/finkirv/
Visit my very special website at http://members.shaw.ca/finkirv4/
Visit my CFSRS/CFIOG ONLINE OLDTIMERS website at http://members.shaw.ca/finkirv5/
--------------------
Irv Finkleman,
Grampa/Ex-Navy/Old Fart/Ham Radio VE6BP
Calgary, Alberta, Canada
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Old April 17th 04, 06:23 PM
Richard Clark
 
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Default

On Sat, 17 Apr 2004 16:47:04 GMT, zeno wrote:

Make sure your RF ground is independent of the house AC
safety ground. I also use a constant voltage transformer and a good power
conditioner because the AC here is a mess.


Hi Bill,

The combination of these two statements could kill you. If AC is a
mess, and if you have your own independent ground, then there may come
a day when you connect/disconnect a wire between them (and it is
guaranteed to be there) that has enough potential to blow your fuse.

Think about it. The most common method of connect/disconnect involves
the use of both hands, one wire in each (think of holding onto shelled
connectors), with a path across the heart - classic killer scenario.

Having separate grounds is against code. Being against code it is
also a loophole for insurance to deny a claim if misfortune comes of
this misapplication. Having separate grounds is also bad engineering
and bad noise control. In short, there is no good reason to do it
when it needs to be done right.

What you have the potential for are problems called "ground loops."
Closing or breaking those loops is what brings those problems. There
was a thread in the last week with excellent links to how to do it
right. I don't have them at hand right now, but you should research
or prod me for more.

73's
Richard Clark, KB7QHC
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