Electric fence interference

[Mick]

Anybody know of a manufacturer or have a circuit of an active filter to
remove noise from telephone lines caused by the pulses from farmers electric
fence. Especialy causes disruption to any data signals.
- Mick

[Adrian Brentnall]

Hi Mick

I'd imagine that this type of interference would be very difficult to
filter out - and you might get further by raising the matter with
either the farmer, the manufacturer of the fence, or the telephone company
(possibly in that order)...

I'd guess that the electric fence may be old or defective - or maybe it runs
for a long distance in parallel with your 'phone line - but I've never heard
of this type of interference.

The 'phone company (as a last resort) could maybe have words with the farmer
- as he's interfering with the service that they're providing. For 'normal'
interference than filtering at the phone socket is a possibility - but I'd
expect that this interference in fairly 'broadband'..... depending on the
type of fence in use...

Hope this helps..?
Adrian - G0THW - Suffolk UK

[Cap'n Crunch]

"Mick" <mi...@anotherworld.com> wrote in message
news:C4LU5.17223$vA4.3...@news6-win.server.ntlworld.com...

> Anybody know of a manufacturer or have a circuit of an active filter to
> remove noise from telephone lines caused by the pulses from farmers
electric
> fence.

Mick...
Get ahold of the Phone Co., they will install a line filter at the
service entrance of your home at no charge to you. It may or may not solve
your problem, but at least it's a start. If it doesn't work, you'll have to
contact the farmer or the fence manufacturer as the earlier poster
mentioned.

[Jeff Griffith]

My son recently found an article in an old QST that discusses electric fence noise.
The causes they identified are:

1) Defective line transformer
2) Weeds shorting the fence to ground
3) arcing at insulators
4) arcing at poor gate interlocks

The author used an inexpensive, broadband receiver (an old $5 AM set would
work well) and walked the fence. In his case, he ruled out the line transformer/pulse
generator first as the noise did not change when the cover was removed. Weed
induced noise was eliminated as the fenceline was neatly mowed and trimmed.
He walked the fenceline listening for noise pickup. The noise pickup tended to
be worst at locations that were visibly corroded, and when the spot was shaded,
the arcing could be seen. His fence had a bad spot where the fence wire was pinched
by the staple holding it to the rail and at a gate. He proved these were the only two
trouble spots by turning off the fence, shorting these spots and restoring power to the
fence. When power came back on, the noise could not be heard.

So, sounds like something to do at night when sun noise (in both the HF
and lightwave bands) is at a minimum, but take a flashlight to check for visible
clues.

The ARRL Handbook has a couple of articles on RFI reduction that you might
check as well.

The key is whether your picking it up through ground circuits or the air. If your phone
line runs close to the fence, you might be picking it up through ground currents
induced by the fence. In that case, the line filter will help. But if the fence is
arcing, you may have direct, RF pickup in your handset. See if your TV
or other radio equipment is effected (again, cheap AM receivers may be the
best for this). In the case of arcing, you're dealing with a spark-gap transmitter.

Jeff Griffith

Cap'n Crunch <kcfa...@tir.com> wrote in message news:TtQU5.1723$wq3.4...@nntp3.onemain.com...

[DXE1999]

Two or three mile run of wire, insulated from the ground, probably in a
square..........Hmm. At night or whenever the cattle are not in that field,
you could ask to use his antenna.

[Mick]

Got a 130ft lighthouse just outside the door - that might suit you better

"DXE1999" <dxe...@aol.com> wrote in message
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