Noise Source - Any clue from the signature?

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Have been seeing this noise source signature from time to time.  It comes and goes with no regular pattern.  The screen shots show how it progresses over about a 15 minute period.  Any see it before or have a idea the source from the signature?

John K3MA







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John-K3MA

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Posted 2 years ago

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Norm - W7CK

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I'm just guessing here but someone in the neighborhood may have installed a solar system.   Or, you may have a bad PS, or wall wart.    Run your equipment from a 12v battery, turn off ALL of the electric going to your home and see if it is still there.  If it disappears, its most likely coming from your home.  If it is still there, then its somewhere in the neighborhood.

Until the industry can clean up the RFI both Solar controllers and the new variable speed motors for pools, AC units, hot tubs, etc., they should be outlawed....   Its going to get to the point where HF and VHF to some degree, is unusable in suburban neighborhoods.....
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David Warnberg

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I'm about 99.9% certain that is Solar.. I have a solar pool pump and as is ramps up (more sun shining) it does exactly that.

I traced it to the variable speed DC pool pump (lorenz) I have the ability to switch mine off and the noise goes away, they also make solar well pumps... It also saves me over 80 bucks a month in electricity so if it is a neighbor you can talk with them about it but very little can be done without some expense. Take a look at April 2016 edition of QST.. "Can Amateur Radio and Solar Power Coexist"

First is solar off on 40 meters, second is solar on 40 meters


(Edited)
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Roy - W5TKZ

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My next door neighbor has an air conditioner with a variable speed fan in the outside unit. We tracked the noise and he adjusted the fan to run at max all the time. The noise is still there but is now close to the base line noise so it presents no problem.

Roy - W5TKZ
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Jim Jerzycke

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It's really sad that the FCC lets these manufacturers "self certify" their equipment. They leave out a few $$ worth of parts that would filter the noise out, and put them in plastic cases that do nothing to bottle up the noise.

73, Jim
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Norm - W7CK

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Actually it's more than just a few parts.  It's VERY hard to clean up the RFI generated by the solar charge controllers and I don't know of anyone who has actually cleaned them up 100%.   There are usually birdies every few kHz up and down all of the bands, just like in the pic above.  Its the oscillators in the controller that are actually switching the panels on and off to produce the particular voltage they are set for.  The cables going from the controller up to the panels and the panels themselves then become giant transmitting antennas radiating the noise.

The pump motors can be quieted down if you get inside the cabinet, add some chokes and make sure its grounded properly to a ground rod at the device.  No one does that though.....
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K6OZY, Elmer

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I have an issue with the solar system on a neighbor a few homes down.  I'd love to hear the group's social engineering methods at convincing someone to even consider fixing the issue.   At Field Day, a neighbor near our operating area had an object in their home  start freaking out Saturday AM severely impacting our operations.   We narrowed it down to that location, and the person there told us to pound sand.  Sigh..
(Edited)
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Norm - W7CK

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Hey Chris.

A neighbor 2 doors down from me is installing panels on his roof as I type.  We'll see how bad they are.

I've been told that the FCC is responsible for enforcing RFI rules.  I've heard rumors that some people have actually called them and report the offender.  The FCC verified the RFI and notified the owner of the equipment requesting that they fix it.

This was a couple years ago and now that the FCC has been cut back to the bone, I'm not sure if this is still possible or not.   If the neighbor's solar system causes a bunch of RFI when they come on line in the next day or two, I'll be forced to call and see what happens.    
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John-K3MA

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Not coming from my house.  No pools in the area.  No new solar panel installs in the area.  Is there something else Solar that could be causing it?

If it were Solar when would the interference be evident.  I have not started to keep a log of the interference as I have only seen it a couple times but would be nice to understand the Solar interference daily timeline.
(Edited)
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Norm - W7CK

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If it is a neighbor's solar system, it would only be present during daylight hours when the panels are producing power and the charge controller is switching to convert it to the proper load voltage. 

I've seen solar systems, pool pump motors, RV charge controllers etc., cause lots of interference even when they are 100 yards away.   Some are absolutely unbelievable.

Were you able to run your flex off of 12v and turn ALL OF THE POWER off to your home?
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Rick

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I have a similar problem only on 20m, and it's constant. The noise peaks are close to every 60 Hz but a little lower than that and it is not something I've had for ever. Not exactly sure when it started but I need to try and shut my main off and run the rx on a battery to see if it's local. I'm al oat certain, based on the ability to null it out with my antenna, that' it's somewhere in the neighborhood.
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Norm - W7CK

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Nearly all of the new clothes washing machines produce RFI.  Old washers would only run for 30-45 minutes.  The new ones can run for hours!  You can usually tell if it is a washer because it will be there for a few minutes and then stop, then start up and run for a bit then stop.   Drives me nuts!
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John-K3MA

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That is one I did not think about and I have seen a few furniture/appliance delivery trucks in the area over the past few months.
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John-K3MA

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Yes I turned off the entire electical feed to the house.  I do that every 6 month to catch any new or occasional sources of noise within my own control.  I live in a HOA development of 21 houses and my antennas are close to the house roof to keep them from being seen from the road and hence out of the eye of the those that might complain to the HOA.
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David Warnberg

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Any new variable speed DC motors around?  You live on a pond?  Did they happen to put in one of those pond fountains?

Just thinking outloud
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David Warnberg

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Another thought, you didn't mention if it's more daylight hours interference or evening/night time.. anyway another major pain is the DC converters for landscaping lights.. random sometimes as when the power goes out homeowners forget to go set the clock right on them so they come on at weird hours.. also some of the new LED lights can cause issues as well.
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Norm - W7CK

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I am curious to know if the interference ever disappears for a time, or is it there 24/7?
(Edited)
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David Warnberg

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from original post "Have been seeing this noise source signature from time to time.  It comes and goes with no regular pattern"
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Norm - W7CK

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Sorry, I did read your post but it was a while ago.   Do any of your neighbors have an RV parked next to their house?  I know the chargers for them are pretty noisy and they turn on and off a lot.

I know there were some Feit LED canister lights being sold through the Club stores that cause all sorts of RFI.  A friend of mine bought a couple and put in his kitchen ceiling.  The noise from those lights carried 3 doors down the street from his house.  Its possible someone in the neighborhood bought a couple.  That would account for the on / off nature of the noise.  Some of the newer lights are so bad, it appears the FCC is going to create an investigating committee to look into the matter.   I believe I read that in a QST news email...

The only way you'll ever know is to sniff it out with a portable AM receiver......
(Edited)
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David Warnberg

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No worries Norm, not my post but your idea's are also spot on.  I personally use a SDRplay, short antenna and a laptop and go looking for RFI.. you'd be surprised what you can find..

Funny thing, the FLEX-6500 made me more aware of the issue

73's

David
(Edited)
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John-K3MA

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Thanks for the suggestions.  No RV in the area and no pond pumps that I have seen over the 14 years living here.  Actually, my house is loaded with Feit LED lights from Costco and they are clean.  I have not seen the interference since my last screen shots.  At the time it was happening I went to the two next door neighbours houses to see if their air conditioners were running and they were not.  I do have a SDRPlay hooked to my laptop so next time it happens I will try to walk around and see if I can sniff it out.

It should be easy to find the offending location as it is very strong and there are only 21 houses on 3 streets in my subdivision.  The only RFI I have seen stronger is from a Panasonic Plasm TV and lucky for me it is my own and not used when the Flex is in use.
(Edited)
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Norm - W7CK

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It will be really interesting to know what you find John.  Please be sure to report back so we might all learn something.  Thanks.
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Norm - W7CK

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Were you ever able to track down that noise source?
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John-K3MA

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Norm thanks for asking.  I have not seen it again but I am ready to track it down when it shows up.

John
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Norm - W7CK

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I ask because I had the same EXACT pattern that David posted snaps of.   The birdies were from 80m all the way through 17 meters.   They were sharp but pulsated up and down.  The entire HF spectrum was pulsating.  This went on for about 2 hours then suddenly stopped.  I have no idea where it was coming from.   If I see it again, I'll try to track it down.  I'm guessing it was a washing machine.

Norm - W7CK
(Edited)
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John-K3MA

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It would be wonderful if we were able to collect and share panadapter signatures of different noise sources.  If that was available then troubleshooting would be some much quicker and easier.
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Reggie-k6xr

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I have a 50 panel solar system and no problems with it at all. panadapter is always clean on all bands
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Norm - W7CK

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If that's the case, please share the make and model of all equipment in your system, otherwise its useless information....  Most are noisy....
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mikeatthebeach .

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Well, a Noise Sense Antenna and a main Antenna summing together
with a DXE NCC-2 Amplitude & Phase could possibly null it out. 
The two slice SCU ANAN 200D can do this. 
Hope Flex gets this going feature on  their 6700.
If someone could do it on a single SCU that would be a major technical 
advancement 
73 Mike
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John-K3MA

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On the surface this seems like a great feature on the Anan.  However, I found in practise for the noises at my location and the way I operate that it was a PIA.  FIrst it took some playing with the joy stick like control interface to find the point in which the noise would be minimized or nulled.  The when I finally found that point the noise source would change pattern and I would have to find a new null or the DX station I wanted to work was gone.  If you have a single non changing source of noise then I agree it would be useful but until the software is capable of recognizing these kinds of noise patterns and adapting to changes then that feature is just not useful to me.