TopBand: More Electric Fence

[w8ji.tom]

Hi Ralph,

> pulses right up through 2 meters. In each case this clicking pulse
> generator is attached to an ANTENNA (the fence) and it will and does
> radiate. The 1950s noise blankers in all modern radios (tried them all)
> is a clipping circuit. When strong local (1,000 mile 30-60 over S9 ham
> signals) come on the air anywhere within the radios roofing filters
> passband clipping occurs. Clipping equals square waves, square waves
> equals harmonics (intermod), intermod equals no work.

A few years ago my neighbor had a fence to keep deer out of her garden.
Like your case, the fence was good.

I added a 1 mH RF choke (mounted across an insulator) in series with the
feed from the charger, and bypasses (UL/CSA rated .01 mFd caps) on the
power feed. The noise dropped about 50 dB with this small change.  

>   The one thing I discovered that does work is a power outage. 

Another thing that sometimes works is grounding the fence to a good earth
ground. No voltage=no noise.
But neither cutting power lines or disabling a neighbor's fence is a good
idea.

You might buy them a brand new charger for xmas, and install RFI
suppression devices in it before wrapping it up.

GL Tom

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