"Rick" wrote in
:

Owen,
You bring up some very interesting points, precisely what I was asking
for in my original post.
Thank you very much for your assistance.
My theory right now is this:

I have found 2 noisy poles using 440 MHz, both 1.2 miles from me. I
HOPED that they would solve my 80 meter problem, once repaired.
As I go lower in frequency, down to 10 meters using vertical whips, I
confirm that the noise can be heard farther away, as much as about 1/2
mile on 10 meters.

I am not surprised. The directivity of the 'antenna' varies with
frequency, as may be the power radiated.

Trial BPL emissions that I measured could be heard above the noise on 40m
in a mobile station more than 1km from the trial area. Remember that this
was an emission that its promoters (including the FCC) asserted would not
cause interference.

I am assuming that the 2 MHz component of the broadband noise is being
conducted on the lines with very little attenuation for the 1.2 miles
to my house where it is 20 over 9 on a Beverage parallel to the lines.

That antenna configuration maximises coupling to the currents flowing on
the power lines.

Using my loop at 2 MHz I am essentially unable to get any bearing
because the source is essentially a couple miles in length. ????????
And I can't get any significant distance away from the power lines.
(One place on my property is 200 yards from the lines but the loop
can't determine a null. Yet it does fine with locating BCB stations,
so I think it should be usable if the noise was a point source).

But you are not limited to taking bearings from on your own property.

I will say again, if you are close to the power lines, eg within say, a
quarter wave, the loop mutual coupling with the power lines will reduce
its effectiveness for obtaining a valid bearing.


Although the power lines act as a very long antenna, I have had no
difficulty locating BPL injection points using the loop nulls.
What frequency do you look at for BPL? upper HF (10-20 MHz, where it
looks more like a point source?)


If you stand under the power lines, you won't get a result, you need
to move
away from them, you should readily get a good set (ie reliable,
convenrgent) of cross bearings.

I can say that again!


I am failing at that so far, see above.


Sure you can look for interference at 70cm or at ultrasonic
frequencies... but that won't work unless the source is truly
wideband.

This statement puzzles me. Can you please explain more? Can it be
that the poles which clearly
show lots of noise at 440 are NOT the ones causing my problem at 80
meters? i.e. can there be defects which generate noise peaking at LF
and not detectable on 440?

It is not just a matter of whether a fault (eg a leaking bushing) creates
emission of constant power density from DC to daylight, the lines,
earthing system etc all introduce frequency effects on amplitude. You
could easily discover a relatively noise fault on 440 that is not the
root cause of high 1.8MHz emissions at your location.

My advice is that if you sense emissions at some secondary frequency,
always relate it back to the primary problem. It is OK if the power
company wants to locate faulty insulators with an ultasonic detector, or
a UHF detector, but when they have 'repaired' the fault, the valid test
of whether *your* problem is fixed is measurement or observation at the
frequency at which you suffered interference.

It is just a matter of logic.

For example, if you report a problem on 1.8MHz, and the power company
attends. They report that they found 3 faulty insulators and 1 case of
loose hardware using their ultrasonic detector and sledge hammer and
fixed them. Your problem must now be solved.

No, your problem is only solved when the interference at 1.8MHz has gone
away, it doesn't matter how many other faults they found and fixed while
investigating, until they fix the one(s) that cause your problem, the
problem is resolved.


The other thing is that if you make a complaint, demonstrate
emissions at 70cm, and they fix them at 70cm, what do you do if they
didn't solve your primary problem.

That would be my worst nightmare. That's why I am looking for a better
understanding as I asked above.


IMHO, better to measure the problem at the primary frequency, report
the real problem, not the cause, but the primary impact on yourself.

I did that, starting 11 months ago. I played dumb, just said here's
my problem.
The power company guy who has been trying to help me has a wideband
spectrum analyzer, and uses a 300 MHz-1GHz LP antenna, hand held. For
low frequencies just a pull-out whip. He prefers to use his hand held
ultrasonic device with headphones, probably because he has had good
success with it. He let me experience it once and it definitely can

Ok, they are all techniques for finding faulty equipment... but if they
don't measure the emissions at your place before and after, they have not
proven that the faults found contributed to the interference problem.

Is that hard to grasp?

hear a problem on a pole. So I'd say right now he has the best
capabilities at ultrasonic, and I do at UHF (with my 8 element Quagi
and sensitive receiver), and neither of us does at low HF.

Again, I earlier made the point that detectable noise is not necessarily
actionable. It would be unreasonable to require power line emissions to
be undetectable. In that environment, measurement of the emission level
either in absolute terms or relative to ambient noise (the degradation
caused, if you like) may be relevant to whether the case is actionable.

My experience with BPL particularly, and also with weak signal working is
that hams, by and large, don't have much interest in noise, and therefore
much knowledge of noise as it limits the communications channel.

An anecdote: A notable VHF weak signal operator reported "I am suffering
interference at S9 to 40 over S9 on 2m" led to my question given that he
has a high gain array with masthead preamp etc "what does S9 mean?". I
was told that his system was 'calibrated', he adjusts the transceiver
input attenuator so that the S meter reads zero on band noise.

In the jurisdiction, there is a standard that limits power line emission
field strength (specified in uV/m) from power lines, and if it could be
demonstrated that the emission exceeded that, there was no question, it
needed to be reduced, not eliminated, but reduced to comply with the
standard.

But, S9 mean't nothing in terms of the standard, it did not providing a
compelling case of non-compliance.

BTW, in this jurisdiction, if a leaky insulator also affects local
broadcast reception, a report along those lines is more likely to get
action.

Owen

"Rick" wrote in message
...
I have been wrestling with power line noise here for almost a year.
Power company hasn't been very successful in locating it so I started a
coordinated search.


My local utility has one tech who does power line noise investigations and
I'm happy that he solved my problem. He identified three "problem poles"
and a week later, the noise was gone.

I can't answer your question about how far power line noise will travel but,
since you've put so much effort into this already, this next may be worth
doing, too.

One of the tech's tools was an audio detector, which he aimed toward the
tops of all the poles on my block. It was a 16-inch clear parabolic
reflector with a microphone mounted at the focal point and an amplifier
feeding headphones and a meter. The tech was listening for the sound of the
offending arc. Never mind the RF -- find the faint sizzling noise by ear!!

For a small fortune, these guys will sell you one: http://www.paradish.com/

You could definitely make one. This article
http://www.solorb.com/elect/misc/bige/ illustrates the idea (from a Google
search of "big ear" microphone) and it looks like he used an old wok.
(Are woks parabolic.)

So, if you want to impress the power company ...

Sal

Sal M. Onella wrote:
"Rick" wrote in message
...
I have been wrestling with power line noise here for almost a year.
Power company hasn't been very successful in locating it so I started a
coordinated search.


My local utility has one tech who does power line noise investigations and
I'm happy that he solved my problem. He identified three "problem poles"
and a week later, the noise was gone.

I can't answer your question about how far power line noise will travel but,
since you've put so much effort into this already, this next may be worth
doing, too.

One of the tech's tools was an audio detector, which he aimed toward the
tops of all the poles on my block. It was a 16-inch clear parabolic
reflector with a microphone mounted at the focal point and an amplifier
feeding headphones and a meter. The tech was listening for the sound of the
offending arc. Never mind the RF -- find the faint sizzling noise by ear!!

You got it.

For a small fortune, these guys will sell you one: http://www.paradish.com/

You could definitely make one. This article
http://www.solorb.com/elect/misc/bige/ illustrates the idea (from a Google
search of "big ear" microphone) and it looks like he used an old wok.
(Are woks parabolic.)

The old style cheap woks are parabolic. The newer ones which have a flat
bottom are not. I have a 24 inch Al parabolic dish. It isn't very
stealthy, but it's lighter and bigger than the woks.

There are some nice features about hunting down RFI problems with sound.
That parabolic reflector can be aimed right at the pole, and in
combination with the short wavelength esp at ultrasonic frequencies will
let you zoom in on the problem pretty quickly. Trying to close up DF
with HF is like trying to change directions on a cruise ship.

So, if you want to impress the power company ...

If you are doing it near your own house, DO check in with the neighbors
telling them that you are locating the source of noise, and it might
eliminate any interference they might be getting now.

- 73 de Mike N3LI -

On Fri, 10 Jul 2009 10:39:46 -0400, Michael Coslo wrote:


If you are doing it near your own house, DO check in with the neighbors
telling them that you are locating the source of noise, and it might
eliminate any interference they might be getting now.

- 73 de Mike N3LI -

I use a slightly different approach. I have a battery powered marine RDF
and all I have to do is align it and follow it to the offending pole, or
house. Poles I can usually get fixed if I convince them it is a fire
hazard. Houses tend to have people who could care less about your hobby
unless you use the fire hazard thing again.
Bill Baka

"Michael Coslo" wrote in message
...


snip

There are some nice features about hunting down RFI problems with sound.
That parabolic reflector can be aimed right at the pole, and in
combination with the short wavelength esp at ultrasonic frequencies will
let you zoom in on the problem pretty quickly.

Funny ... how our minds work -- or don't work. I wrestled with the idea of
ultrasonic, trying to make sense of snooping for weak, high-order harmonics,
vice audible sounds. Despite a quarter century of regular exposure to
satellite dishes, personal and professional, I overlooked the fact that
dishes are more directive at shorter wavelengths.

Doh!

Sal

This is a long thread and I hope I read enough and am not repeating.

I've been involved in a power line noise problems here in McHenry
Illinois for the last year and can make a few comments.

There are some very good references on the ARRL Web site. I've read
them, one of the books and consulted with Gene Preston, K5GP a pro and
one of the paper's authors. They should be top on your list of things
to read.

Main page:
http://www.arrl.org/tis/info/rfi-elec.html

This is good, but long:
http://www.arrl.org/tis/info/rfi-elec.html

A good summary:
http://www.ctdxcc.org/powerlines/

Some others:
http://www.arrl.org/tis/info/pdf/0112068.pdf
http://www.egpreston.com/RFItalk.ppt

There's lots more on-line, but these will make you an expert quickly.
(:-)...

Power line noise is almost always quite broadband. It won't just be
on one band. Therefore, it is best to hunt on the highest frequency
available that hears the noise. The noise travels further at lower
frequencies and pinpointing a source is more difficult. Three pros I
have talked to say this. The author of one of the books uses a
modified TV antenna to get up to 900 MHz and above. An Engineer at
the equipment manufacturer, Radar Engineers, says the same thing :
hhtp//:www.radarengineers.com

They make an ultrasonic ear, a 330 MHz beam/Rx, and a wide range
receiver/spec analyzer for power line noise hunting. The local power
co here (ComEd) uses all these.


In addition, at higher frequencies you can get more gain in a
relatively small size and a resulting narrower beamwidth to better ID
the pole. I happen to have the same Cushcraft beam Gene Preston uses
(shown in his paper below) and it works nicely to pinpoint a pole or
when further away, a region of radiation.

My measurements show the same thing. The noise is at a lower level at
higher frequencies, so some gain may be in order. I also use preamps
at times.

I have access to the very same ultrasonic and 330 MHz.equipment. I
also have a 2M beam, 450 beam, 700 beam and 1296 beam, spec analyzer,
yadda, yadda....

We're pretty heavy into this and getting impatient with ComEd.

The ultrasonic will ONLY hear arcing that is in the air OUTSIDE
things. Our arrester problem has NO ultrasonic signature (our problem
appears to be up to 100 arresters causing noise 15dB above the level
when the line is de-energized).
The ultrasonic dish can identify an individual insulator or arcing
component.
Hot clamps and ground wires, yes ground wires, can be a significant
source. Including the large staples that hold the ground wire to the
wooden pole !!

The comments about making sure *your* noise is fixed is right on as
well. Identifying the particular signature of the noise should also
be done. This is with an O-scope so you can see the time signature
(the wave shape) This can also help identify multiple sources.


We currently are waiting for the manufacturer to test 30 arresters
that were swapped out. These arresters are 100% tested for RF noise
and I'm worried that the test is bad.

FYI:
They also have a 22 blank cartridge in them. If the arrester fails
such that is conducts and heats up, the cartridge fires and blows the
snot out of the ground connection to free up the line.

Good luck
73, Steve, K9DCI at arrl dot net

On Sat, 11 Jul 2009 21:56:47 -0700, Noskosteve wrote:

This is a long thread and I hope I read enough and am not repeating.

I've been involved in a power line noise problems here in McHenry
Illinois for the last year and can make a few comments.

McHenry? I lived there from 1948 to 1955 in the McCollum lake area.
Corn fields everywhere. When I went back in 1993 the old neighborhood was
still there but the cornfields had turned into condo-fields.
I would have hoped the new construction would have put the new wiring
underground so you would not have a problem.
Are things still on poles?

There are some very good references on the ARRL Web site. I've read
them, one of the books and consulted with Gene Preston, K5GP a pro and
one of the paper's authors. They should be top on your list of things to
read.

Main page:
http://www.arrl.org/tis/info/rfi-elec.html

This is good, but long:
http://www.arrl.org/tis/info/rfi-elec.html

A good summary:
http://www.ctdxcc.org/powerlines/

Some others:
http://www.arrl.org/tis/info/pdf/0112068.pdf
http://www.egpreston.com/RFItalk.ppt

There's lots more on-line, but these will make you an expert quickly.
(:-)...

Power line noise is almost always quite broadband. It won't just be on
one band. Therefore, it is best to hunt on the highest frequency
available that hears the noise. The noise travels further at lower
frequencies and pinpointing a source is more difficult. Three pros I
have talked to say this. The author of one of the books uses a modified
TV antenna to get up to 900 MHz and above. An Engineer at the
equipment manufacturer, Radar Engineers, says the same thing :
hhtp//:www.radarengineers.com

They make an ultrasonic ear, a 330 MHz beam/Rx, and a wide range
receiver/spec analyzer for power line noise hunting. The local power co
here (ComEd) uses all these.


In addition, at higher frequencies you can get more gain in a relatively
small size and a resulting narrower beamwidth to better ID the pole. I
happen to have the same Cushcraft beam Gene Preston uses (shown in his
paper below) and it works nicely to pinpoint a pole or when further
away, a region of radiation.

My measurements show the same thing. The noise is at a lower level at
higher frequencies, so some gain may be in order. I also use preamps at
times.

I have access to the very same ultrasonic and 330 MHz.equipment. I also
have a 2M beam, 450 beam, 700 beam and 1296 beam, spec analyzer, yadda,
yadda....

We're pretty heavy into this and getting impatient with ComEd.

The ultrasonic will ONLY hear arcing that is in the air OUTSIDE things.
Our arrester problem has NO ultrasonic signature (our problem appears to
be up to 100 arresters causing noise 15dB above the level when the line
is de-energized).
The ultrasonic dish can identify an individual insulator or arcing
component.
Hot clamps and ground wires, yes ground wires, can be a significant
source. Including the large staples that hold the ground wire to the
wooden pole !!

Still poles?

The comments about making sure *your* noise is fixed is right on as
well. Identifying the particular signature of the noise should also
be done. This is with an O-scope so you can see the time signature (the
wave shape) This can also help identify multiple sources.

A good O-scope can be many kilobucks. Mine was, Tektronix, but worth it.


We currently are waiting for the manufacturer to test 30 arresters that
were swapped out. These arresters are 100% tested for RF noise and I'm
worried that the test is bad.

FYI:
They also have a 22 blank cartridge in them. If the arrester fails such
that is conducts and heats up, the cartridge fires and blows the snot
out of the ground connection to free up the line.

I can just imagine a really hot day.

Good luck
73, Steve, K9DCI at arrl dot net

Bill Baka
Real mail is
My parents transplanted me to California.

On Jul 9, 11:58*am, "Rick" wrote:
I have been wrestling with power line noise here for almost a year.
Power company hasn't been very successful in locating it so I started a
coordinated search
on my own. Thinking if I can tell them for certain which poles have the
problem they can confirm and maybe fix.

The noise is a deafening 20 over 9 on 80 meters which makes DXing on 80 and
160 impossible.
The noise can be heard at my QTH as high as 10 and 6 meters but it isn't
troublesome on those bands because it can only be heard at about an S7 level
when the yagi is pointed at 210 degrees.
I thought maybe my means of analysis might be interesting to discuss and
maybe others would have other suggestions.

There are 7000 volt lines running on a highway past my house. *Tracking the
source on 80m seems impossible.
I made a 2 ft square loop antenna, which has some directivity but the noise
level using it seems to not change
much as I travel the highway. *On 10 meters, using a 4 ft whip on the car,
the noise is also hard to localize but
seems to increase in the vicinity of 1 mile from home. *6 meters using a
whip is similar. *I found that if I'm close
enough that the 6 meter signal is around S7 I can switch to 2 meters and
again peak the noise by driving slowly up and down the road.

So using this technique and driving 2 miles in each direction I have managed
to find 2 spots, one on the highway and one on a cross road, each about 1..2
miles from the QTH. *I then built a 432 MHz 8 element quagi beam which
enabled me to pinpoint the offending pole at these two locations. *(I have
put a LOT of effort into this project !)

At this time I am waiting (hoping) for a return call from the power company
to verify my dicovery.

So my question for the group - Can either of these locations 1.2 miles
distant cause such horrendous noise levels on *80 meters? *Is it possible
that a weaker noise source much closer to me is the culprit or are all of
the power line malfunctions detectable on 440 MHz?

Rick *K2XT

Sounds about like a problem I had. I used an AM 60s vintange shirt
pocket AM receiver to find the offending transformer. When I called up
the power company I gave them the pole number and street address and
didnt tell them I was a ham radio operator. Instead I told them it was
interfering with me listening to my favorite talk show. They came out
the next day.

Jimmie

...I used a ... shirt pocket AM receiver to find the offending transformer.


Thansformers themselves VERY, VERY, VERY rarely make noise.
Insulators, connections and other connecting hardware are the cause.

Mchenry / McCollum Lake

Poles.

I'm actually in Wonder Lake. It's a Wonder it's still a Lake because
no one wants to have it dredged (but they surely want the "lake").

73, Steve, K9DCI atarrl point net

Noskosteve wrote:
...I used a ... shirt pocket AM receiver to find the offending transformer.


Thansformers themselves VERY, VERY, VERY rarely make noise.
Insulators, connections and other connecting hardware are the cause.

Mchenry / McCollum Lake

Poles.

I'm actually in Wonder Lake. It's a Wonder it's still a Lake because
no one wants to have it dredged (but they surely want the "lake").

73, Steve, K9DCI atarrl point net

Sad to hear that. I used to swim in it and in 1954 I could watch the
steam engines hauling the daytime commuters to Chicago on the far side
of the lake.
Times change.
Bill Baka