Noise

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  • Updated 2 months ago
For the past week I have been getting sporadic noise on 17 and 20 meters (20 The worst).  It lasts anywhere from a few minutes to an hour or more. It is consistent at about s7.

If I happen to receive a signal stronger than S7 I can hear it.

It doesn't vary - it is flat across the spectrum.  I can see spikes that I am sure are signals if they could override the noise.

Just now, while typing this post the noise went away and  the noise level on 20 is about s4 For a certainty it will come back.

We have underground utilities in my community.
I am running a flex 6500 barefoot into a hex beam.

I will appreciate any advice or solution.
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Gene - K3GC

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Posted 2 months ago

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Photo of WH6HI - Pat

WH6HI - Pat

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Most likely the Solar Flares this past week....
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Gene - K3GC

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Would that account for it lasting from a few minutes to an hour or more?
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Mark WS7M

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If you can catch a screenshot that is always helpful.

I currently have this beast on 40m and other places.  It is some neighbor with some new toy:


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Bill -VA3WTB

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Does the WNB work on that noise?
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Gene - K3GC

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Doesn't touch it.
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WH6HI - Pat

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Does this noise repeat every 200 KHz or so.  If it does it may be someones switching PS.  In my case I have something similar and located it and it is a LED street light that the Switching PS is radiating the noise. 
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Gene - K3GC

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It's steady across the band
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Gene - K3GC

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screen shot with S7 noise across the 20m band

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Bill -VA3WTB

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I am surprised there is no setting with the WNB that does not help..It looks like electrical noise...
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Roy - W5TKZ

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Gene,
Have you tried to find the beam heading for strongest signal with your beam? Maybe one of your neighbors has an air conditioner or other appliance that is acting up. In any case, tracking noise is a step by step process that only you working with your equipment can do. Those of us on the outside can only suggest where you might look.

Good luck

Roy - W5TKZ 
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Stan - VA7NF

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Just finished Phase 1 of reducing noise at a friend's shack which matched your description.
It was S9+5 flat, no spikes, from 160 to above 80 (didn't need to go any higher).
Turned out to be 2-4 bulb LED fixtures in the living room.  Went down to S5 when turned off.

Standard hunting - Start with the radio on battery and shut down the whole house power by the master switch and if that drops the noise turn on one circuit at a time. 

I normally use a short wave battery radio (Grundig satteliit 750) with an external BNC antenna connection, with a sniffer antenna (10 turn tight loop on a short coax).  

Happy hunting.
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WQ2H - Jim Poulette

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I agree - don't underestimate the interference potential of LED bulbs or appliances in your QTH. Also, I know here we have a utility transformer up on a pole about 200 yards away that makes noise when heavily loaded. It's usually OK, but temperatures here in New England have been in the 90s - so it's screaming this week.

My set-up is the old HT on 130mHz using a small Yagi - doesn't work so well inside the house, but you'll usually find what you're looking for right through the walls. You'd be surprised what you'll find walking your average distribution line.

Good luck
73
Jim, WQ2H
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Stan - VA7NF

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Jim,
The power companies are normally very responsive on noise complaints, it is good business to fix a noise problem before the transformer explodes.  Also power line noise represents lost power, thus reduced profits.
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Rick WN2C

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Why do you need +16 db of pre-amp on 40 meters? It appears to me that in the pass band there is no signal and only an s3 noise level.