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[KG7WAQ]

Don't know if this quite belongs on this forum, but I've found I have a "click" noise every 2 seconds or so on my IC-7600 and I see the level jump on my meters (but nothing on the waterfall display). I don't have another HF radio to cross-check, and it happens on both my vertical and 40m dipole. Is this normal atmospheric noise or is something not connected right that is causing this?

[K6AER]

From your description the noise could be coming from an electric fence. Do live in an urban area?

Turn on your noise blanker and adjust the level. See if that helps.

Once you find the noise source you can take steps to reduce the noise at the origian. Type 43 mix toroids will help here.

[W1VT]

I've made 50,000 contacts in the last decade and don't recall hearing anything like this.

Zak W1VT

[W9IQ]

From your description the noise could be coming from an electric fence. Do live in an urban area?

Turn on your noise blanker and adjust the level. See if that helps.

Once you find the noise source you can take steps to reduce the noise at the origian. Type 43 mix toroids will help here.

Mix 31 toroids will be the best for anything HF through 2 meters. It beats out mix 43, 61, etc. But if the noise is a harmonic of a lower frequency then other mixes such as 75 may be better.

But don't apply toroids to an electric fencing system! If it is a modern fence charger, it is better to check for any loose fence wires or wires that are shorting to posts, trees, etc by looking at its amperage meter. Then check to make sure it has a good ground system with at least 6 rods spaced 8 feet from each other.

- Glenn W9IQ

[K6AER]

From your description the noise could be coming from an electric fence. Do live in an urban area?

Turn on your noise blanker and adjust the level. See if that helps.

Once you find the noise source you can take steps to reduce the noise at the origian. Type 43 mix toroids will help here.

Mix 31 toroids will be the best for anything HF through 2 meters. It beats out mix 43, 61, etc. But if the noise is a harmonic of a lower frequency then other mixes such as 75 may be better.

But don't apply toroids to an electric fencing system! If it is a modern fence charger, it is better to check for any loose fence wires or wires that are shorting to posts, trees, etc by looking at its amperage meter. Then check to make sure it has a good ground system with at least 6 rods spaced 8 feet from each other.

- Glenn W9IQ

Glen,

We use toroids on electric fences for years. What is the issue?

[W9IQ]

On the AC cord it may be OK but normally it isn't needed there.

The output from a modern charger is a pulse in the sub millisecond range. Its output is 5 to 10 kV and better chargers can produce more than 50 amps.

Placing ferrite anywhere on the output of the charger can lead easily lead to core saturation which causes non-linear operation (i.e. unintended consequences). It can also reduce the effectiveness of the livestock shock due to its series resistance.

Like all RFI issues, it is much better to treat it at the source. In my experience if there are no shorts or loose wires, it is always a marginal ground system or a very low quality charger.

If the charger is the old "weed burner" type it is best to replace it and start from there.

Have you had a different experience, Mike?

- Glenn W9IQ

[KG7WAQ]

There are electric fences around, but I think all of them (would need to verify) run on battery/solar panels. From that shorting it would cause a RF interference that I would be picking up on the icom?
It does sound exactly like an electric shorting out, I wouldn't have thought that could have been a cause. Is there anything I could install around my power sources to filter that out?

[W9IQ]

It wouldn't matter how the chargers are powered. If they are arcing due to poor connections; shorting to posts, trees, bushes, etc.; or connected to a poor ground system then they can generate noise. Try to talk with your local farmers/ranchers - they don't want poor fence performance so you may alert them to a problem of which they were not aware.  Some advance snooping with a portable radio may zero in on the location. If the fence has a short, you may very well hear an audible 'click' or 'snap' as you get close.

There is little you can do from your end to reduce fence noise. If your coax or house is closer to the fence than your antenna, then proper common mode chokes on the feedline may be effective. Otherwise, adjustments on your receiver may be the last resort.

- Glenn W9IQ

[K0UA]

You may even be able to find it with the AM radio in the car.  Tune to an unused (or very weak) station slot and drive around a bit to listen for it. Of course a portable radio would be good. This is where having an HF rig in the car can be a good thing.

[W9WQA]

i had a repeating pulse,tracked to a battery tender...
started with main breaker...you know...