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
----- Original Message -----
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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