Hey All,
Back last summer I reported on a sudden Electric fence QRN that went from
almost nothing (in fact, so weak most times I wasn?t even sure it was a
fence) to loud when the fence was expanded up next to my property line. It
was to 30-40/9 on 160m s9+10 on 80m ,nearly S9 on 40m, s6 on 20m s2 on 6m
and s1 on 144MHz. This is like water torture enduring a loud pop every 1.3
seconds.
Anyways, I have been ?gently? (this being the key word here) working with
the owner off and on for the past year, trying subtle things like clearing
weeds and small trees (sometimes when he?s not around) and today hit on
something quite significant. Significant enough that it will hopefully
change my contesting experience.
Backtrack a few days ago and he wanders over and sees me working outside and
asks me if the interference is less? I say maybe a little recently. He
said he bought a top-of-the-line new 120VAC charger and installed it a few
weeks ago, believing his solar one was to blame. (it wasn?t the case, but I
digress). He said he also bought a $100 fence checker and fixed a couple
suspect joints.
Anyways, we got to talking and I said I would pop over later with my newly
acquired Tecsun PL-660 to see if I could narrow it down some. I did. Or at
least I thought I had until today.
I had alligator clipped a junction that I could actually HEAR sparking and
he told me about another one which I didn?t touch that day. Just
temporarily jumpering that one junction knocked things down somewhat on
Saturday (when it was dry).
Fast forward to today when I am outside and I hear this clack clack clack of
the fence some 350-400? away. This is the first time I have ever heard it
from my property so I think a tree has fallen on it and go investigate. The
WX is misty/rainy, 7*C, vy slight breeze?..I wander waaay out into a field
next to the woods where he has a few insulators on trees (and not cedar
fence posts) and see some of the electric fence ?rope? perhaps 3/8? or
5/16ths? away from a very wet apple(?) tree and I can actually see the spark
! Holy smokes. It?s high noon here (but overcast) WOW. I can see the spark
from 3? away and hear it likely up to 500? away. Unreal. Is this my
nemesis? Gotta do something.
He?s not home, but I go back into the house and grab a set of thin
nitrile gloves and then a brand new set of dishwashing rubber gloves, put on
dry socks and my thickest rubber boots and go back into the field feeling
quite charged. (no pun intended)
Everything is really damp, but I don?t feel like getting zapped, nor do I
want to be seen unplugging his new charger from next to his house. The part
of the field I am in is very remote.
I twist the insulator on the apple tree and rewrap the rope to stop the
sparking and then instantly the spark sound goes away but I hear it spark on
3 other trees nearby. I do the same there and finally no more sparking.
Go in the house and the QRN on 160m has gone from s9+ 30dB to s9?..and down
to s2 on 40m. For the first time in a long time - Progress! I feel like
celebrating, but more work to do!
Go back into the field, feeling brave and find another 2 trees, much closer
to his house that are barely sparking. Back to shack. Same thing. Lose
another S unit of QRN. This is nice.
Condx for this type of thing must be perfect today. The bigger (new)
fence charger is no doubt making this possible. Only thing better might be
out here after dark to see the sparks too?.but he has a pit bull. (who I
think is locked up in the house all day)
Feeling ultra brave now, I go and get a roll of galvanized fencing wire and
go up next to the horse paddock and bridge the alligator junction from
Saturday and another one I can hear ever so faintly.
I walk the perimeter of the fence and see more junctions that COULD be
sparking, but don?t hear or see anything. Nobody around and the rain and
wind has stopped, so it?s very quiet. Still, I don?t hear anything more.
Maybe this is it.
Back to my shack.
QRN is now down to S7 on 160m, s3 or 4 on 80m and S1 on 40m. Can barely
hear it at all on 20m and nothing above that. Whew !
I think before I go modifying his whole fence I?ll wait and talk to him then
maybe wander over another day and see if I can find any more suspect
junctions even if I can?t hear or see anthing. He?s using what appears to
be a more or less stock very small galvanized U-bolt to join this electric
fence rope together and it makes a pretty poor connection, as the ropes
really only touch directly under the ¼? wide ?U? of the U-bolt or the
saddle. I?ve seen others on the net that sort of resemble a flat figure 8
and have 2 short bolts which I feel might be better. Way more contact area.
Anyways ? I have told him about wrapping rope around his insulators close to
trees and posts, and although a pretty nice fella, I cannot impress upon him
that this is not the correct method and the rope should just sit(float) in
the insulators far away from his posts and trees. (Ie? 10kV will jump a gap,
especially on a wet day!) There is no changing his mind on that.
Also, I think there?s a connection or two inside the horse paddock where
the rope is just tied together (also not great). There are a few small
raspberry stalks touching the fence here and there,a nd grass will grow
later this month, but I will go around with shears and look after that
later.
I just feel so relieved I might actually be able to hear something on the
low bands now w/o having to run the noise blanker (which destroys a low band
during a contest) that I just had to share !
Thanks for listening.
Mike VE9AA
Frank,
OK, very interesting. I guess I had forgotten that ?feature? of very long
and/or travelling wave antennas. Thanks for educating me.
There goes that (troubleshooting) theory then ? shucks !
In any case, at least it gives me some more info and I can hopefully
minimize
the QRM I am currently experiencing by transitioning over to some more
horizontally polarized antennas for some bands that are all verticals now.
I appreciate the help I have rec?d thus far on this list. It?s just a
matter
of getting through to the neighbour (an entirely different issue ; not for
this
list, hi)
Mike VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
From: donovanf@starpower.net [mailto:donovanf@starpower.net]
Sent: August 24, 2015 10:08 PM
To: rfi@contesting.com
Cc: Mike Smith VE9AA
Subject: Re: [RFI] [Bulk] Re: Electric Fence pulsing (will get worse soon !)
POLARIZATION
Hi Mike,
This is a good time to break out your antenna modelling software and give
it a good workout. Almost all of the radiation from wires more than a
wavelength long and installed a few hundredths of a wavelength above the
ground -- such as Beverage antennas and electric fences -- is radiated as
vertical polarization.
Placing a vertically polarized receiving antenna near an electric fence is
doomed to failure unless you and your neighbor can thoroughly clean up
the RFI and then keep it very well maintained.
73
Frank
W3LPL
_____
From: "Mike Smith VE9AA" <ve9aa@nbnet.nb.ca>
Cc: rfi@contesting.com
Sent: Tuesday, August 25, 2015 12:36:56 AM
Subject: Re: [RFI] [Bulk] Re: Electric Fence pulsing (will get worse soon !)
POLARIZATION
Not too much to report other than the owner had a local with a tractor bush
hog the fields lately which did touch on SOME of the weeds. Did the noise
reduce much?
No, not really. If I had to guess, I'd say by 3-6db (at times....) but it's
so up and down, who can tell. Most of the perimeter weeds are still there.
One thing I did notice as of this weekend was that on 20m and 40m the noise
is much less using a horizontal antenna.
I just installed a horizontal ZS6BKW (G5RV-like) antenna as close to the
fence as my all band HF9V vertical.
On my HF9V the qrn spikes on 20m are up to s5 (s7 once in a while) and on
the horizontal multiband dipole, with some small amount of gain in the
direction of the QRN, the spikes are usually S1.....
I've compared EU signals on both antennas and signal levels are pretty much
identical so I know the newly installed multiband dple is not a DOG.
Negotiations with the owner to fix are not going well....but that's not what
I am on here to complain about.
I just wanted to know, that *IF* knowing the spikes are more vertically
polarized than horizontal, would that 'necessarily' mean the affected "wire"
would be vertical in nature? (I am thinking the fence is 2 low horizontal
1000' loops in parallel)
I am nearly certain from various trips over there to where the controller is
physically located, that the issue, whatever it is, is at or very near the
controller and there are a couple 4-5' "vertical" wires in that
area......the rest of the fence is almost all horizontal from what I can
tell. Maybe I am barking up the wrong tree with that hypothesis.
Times when it has been raining or super foggy for a period of time are good
for me as spike levels go way down, and middle of the night to early morning
are good too. (no sun , solar controller...but it's also usually
wetter)...so I think a lot of current is sinking to ground and battery is
going dead often. and/or the poor connection, wherever it may be, is being
partially bridged by moisture.
SIGH.....
Mike VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
-----Original Message-----
From: Mike Smith VE9AA [mailto:ve9aa@nbnet.nb.ca]
Sent: July 30, 2015 3:52 PM
Cc: 'rfi@contesting.com'
Subject: RE: [Bulk] Re: [RFI] Electric Fence pulsing (will get worse soon !)
Further to my last, I just backed the car up about 10' from the fence,
nearest to my property and do not hear it on 2m or 70cm just using the
vert's on the car.
I BARELY hear it on the car's built in AM radio. It's about s7 on 20m using
the SD-330 on the rear deck.
Definitely mostly being propagated from way over where the fence starts out.
~1000 away.
Not sure if this is useful info or not. I guess all it really tells me is
that by the time the fence gets over close to me, the weeds and my antennas,
there's not enough real voltage left to make much noise close to me and the
noise, whatever is creating it, is farther away.
VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
-----Original Message-----
From: Mike Smith VE9AA [mailto:ve9aa@nbnet.nb.ca]
Sent: July 30, 2015 3:38 PM
Cc: 'rfi@contesting.com'
Subject: RE: [Bulk] Re: [RFI] Electric Fence pulsing (will get worse soon !)
Frank, W3LPL gave me an idea....I don't have an aircraft radio or FT-817,
nor is one available to me locally. I don't have a handheld dish and
ultrasonic RX either. (I like the KB4T email that just came through-gonna
save that one) I had asked Frank about using 2m AM with a small 2m yagi and
my mobile rig (FT-857D)(waiting to hear back)...but then I got looking
outside in the aluminum pile and right on top was a 22-el 70cm yagi from my
old VE9MS beacon !
Has anyone successfully used 423MHz AM or SSB for DFing an arcing noise
source? I can (barely) hear the pulses from 1000' away on 2m, but have no
rig or antenna here in the shack to get on 70cm to DF.
Reason I ask, is that it would be much easier wielding around a short 70cm
yagi than it would be one for 2m. I don't have anything for 2m with a short
boom, but could dismantle the 70cm yagi into a manageable size.
Removing the rig from the car is gonna be bad enough. I wired, bolted,
wedged it in there to stay !....I really should've bought an '817 one year
when I was thinking about it, but never got a 'roundtuit' (RATS!) (hi)
I have just about used up all my neighbourly visits with this guy's patience
so really want to make the next 1 (or 2 if I am lucky) visits be productive
or I fear the "don't come back again" speech. BTDT in a situation 50 miles
away @ a previous QTH.
If I am able to point at a bad connector, wire or a clump of weeds and show
him on the S-meter, that would be superb. At this point, he thinks I am
crazy and was trying to say it was another neighbour with a new fence 1/2
mile down the road in a completely different direction. For some reason he
doesn't seem the least bit concerned that I can touch his fence (and barely
flinch), being a little thin-skinned human. IMHO, Clydesdales would laugh
at the puny jolt they'd receive. I am surprised they haven't run away yet,
quite honestly.
One thing I did not mention til now, was that he has a big chunk of wire
going UNDER the ground where a gate used to be. It's perhaps 6 or 8 gauge
insulated... Wire looks really nice, but I am wondering if there is a nick
in the insulation? (just one idea). He also has a couple gate hooks but no
other half, so the hooks are merely draped over the wire-rope of the fence.
I did hear it arcing (moving the handle made that stop), but I don't think
that's the primary issue as that is the farrrr end of the fence and he has
very little voltage starting out at the near end.
Thanks for letting me complain, rant and pontificate. It is most
appreciated ! Really.
Mike VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
-----Original Message-----
From: J. Gordon Beattie, Jr. [mailto:w2ttt@att.net]
Sent: July 30, 2015 1:52 PM
To: 'dalej'; 'Mike Smith VE9AA'
Cc: rfi@contesting.com
Subject: RE: [Bulk] Re: [RFI] Electric Fence pulsing (will get worse soon !)
Mike,
What frequency bands are being impacted by this fence?
73,
Gordon Beattie, W2TTT
201.314.6964
-----Original Message-----
From: RFI [mailto:rfi-bounces@contesting.com] On Behalf Of dalej
Sent: Thursday, July 30, 2015 12:14 PM
To: Mike Smith VE9AA <ve9aa@nbnet.nb.ca>
Cc: rfi@contesting.com
Subject: [Bulk] Re: [RFI] Electric Fence pulsing (will get worse soon !)
Maybe the higher power controller will burn off the grass. Can only hope.
Dale, k9vuj
On 30, Jul 2015, at 9:02, Mike Smith VE9AA <ve9aa@nbnet.nb.ca> wrote:
So, small update. Seems like when it rains or is extremely foggu/humid
outside the noise goes down.sometimes way down.(mostly overnight)..(solar
charged battery dying?)
I am unable to convince the neighbour he should trim weeds, even though I
told him I never noticed anything until mid-to-late May (when the grass and
weeds really took off here in NB (Ve9)
I checked a bunch of connections and even put the back of my hand on the
fence no farther than 20' from the controller. At 800' from the controller,
I can rest my hand right on it (and I am no Arnold Swatrzenegger)
I dropped him off a paper manual of his controller last w/e and highlighted
(with yellow highlighter) in no less than 8 or 9 places in the book where it
essentially says "weeds are bad..get rid of the weeds"
Hi solution?
He's going to buy a bigger fence controller that runs off 120VAC, instead of
his small to medium sized solar one.
I can't get through to him, even though he says " I didn't change anything
since last year except add the piece of fence near your property" (which is
the part engulfed in weeds..down by his paddock it's 99% open dry ground)
The only saving grace in all this fiasco, is that the noise seems to be
somewhat less since last Saturday I spent ~2 hours going around the 1000' of
fence and trimmed a couple dozen tree branches that were touching the fence,
along with dozens of raspberry bushes and weeds. I suppose if I wanted to
really wanted to get motivated I could trim 1000' of weeds with grass
shears...my weed wacker has recently died.
He's got some farm supply guy who he knows coming over with hopefully a
better fence meter (I couldn't get my Neon bulb one even to register right
at the controller) and hopefully some better experience and advice.
I don't think he believes a thing I am saying.
Exasperated in NB,
Mike VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
From: Mike Smith VE9AA [mailto:ve9aa@nbnet.nb.ca]
Sent: July 25, 2015 5:10 PM
To: 'rfi@contesting.com'
Subject: Re: [RFI] Electric Fence pulsing (will get worse soon !)
Today I walked the fence (well, most of it..the internal divide in 1 spot
was not accessible as there were 4 big Clydesdales there and nobody home at
the house)
I trimmed 9 or 10 tree branches hard up against the fence, 30 or 40 good
sized raspberries bushes, 100+ various types of weeds, but had to leave the
grass. I was only 1 guy with grass shears, tennis elbow and only so much
energy.
All this seemed to make a SMALL difference in the fence's QRM level, though
it does vary from day to day somewhat, so only over time will I know if I
have made any real change with my hour and a half of trimming.
The far end of this rectangular fence is nearly due north of my property
line. When I beam due North, NW or NE, no change in signal level. When I
beam ENE/E, the signal comes up indicating to me the most problematic area
is in the original small paddock in that direction (about East/NE from me).
I can put the back of my hand against the fence near my property and not get
knocked on my butt, so there's very little voltage close to me.
I did come upon a place at the original paddock (ENE) where there was gate
hooks that were merely looped onto some wire rope and one of the hooks was
audibly sparking. I mean, my hearing isn't the best, but I could hear it
from 5' away.
I played with the placement and stopped the arcing, but when I got back to
the shack, there was still noise. He has nice new hardware everywhere, but
is missing the 2 parts of the hooks that would attach to the stationary part
of a gate.
Owner not around, so I really didn't touch the fence nor anything else on
his property. Just trimmed weeds/branches on the outside perimeter.
I have noticed on a couple early mornings when it's been very
rainy/foggy/drizzly, the arcing "signal" is quite weak.(one day I could've
sworn it was off) Whether that means gobs of current are being dumped to
ground all night and the battery is dead, -OR- some of these places that
have less than a stellar connections (galvanized fence wire wrapped around
conductive rope and no u-bolts) are being bridged partially by water, I
don't know yet.
That's all for now.
Mike VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
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Mike, Coreen & Corey
Keswick Ridge, NB
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