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Anyone perhaps able to ID this noise source on top band please?

Chris Wilson All Messages By This Member #15829 10 January 2022 Only daylight hours, AFAIK, and MUCH louder on a big (about 380 feet in circumference) horizontal quad wire loop that along one leg runs parallel to overhead phone and mains LV power lines. On my wide aperture Wellbrook loop about 70 yards away from the overhead lines and 20 yards away from the horizontal loop it's much reduced. The noise lasts 2 minutes or so mainly, disappears and comes back few minutes later. (Usually, but fairly random other times). It's not emanating from my house, it's there running batteries and all power off. If you can spare the time to look any ideas are much appreciated, it's a well defined pattern some may have come across before, thanks. File names should be pretty self explanatory -- Best regards, Chris mailto:chris@...
Martin - Southwest UK All Messages By This Member #15830 Hi Chris, It's typical of a switched mode power supply, which looks to have an approximate 9KHz component. Maybe a car or mobility scooter charger or Solar PV invertor (if it doesn't go off at night it may be one with a power wall / battery bank), variable speed motor / fan drive, but to be honest it could be almost anything these days. I'd build a small loop antenna and try to DF the source if possible. Regards, Martin
Martin - Southwest UK All Messages By This Member #15831 On Mon, Jan 10, 2022 at 01:33 PM, Chris Wilson wrote: Only daylight hours Ah just saw that part. Is it on / off at the same time every day (on a time switch), or does it vary with the weather (Solar PV,? street lamps, heating system) ?
@tigersaw All Messages By This Member #15832 Very similar to an issue I have here, does it sound like a whirring noise if you listen to it? Mine runs for perhaps 20 minutes then 'has a rest' and may restart after 10 minutes or often longer. I identified mine by taking a walk around with a MW radio, turns out to be a faulty inverter in a water pumping station some 30 metres away. Despite positive identification (with the assistance of the Water board themselves) there is no intention of replacing offending item as 'no money in budget'.
Tomasz Lemiech #15844 On Mon, Jan 10, 2022 at 2:47 PM Martin via <martin_ehrenfried=[email protected]> wrote: Hi Chris, It's typical of a switched mode power supply, which looks to have an approximate 9KHz component. Power supplies stop abruptly when the power is switched off. This thing clearly has a spin-up and spin-down phase, both 3-4 seconds long. It might be a large variable-speed motor. An elevator in my house draws similar patterns (it has a soft-start and soft-stop phase in order not to shake the passengers too much). Regards, ? -- Tomasz Lemiech
W0LEV All Messages By This Member #15845 I can not look at the link.? My PC cautions of a possible security risk.?? Dave - W?LEV toggle quoted message Show quoted text On Mon, Jan 10, 2022 at 1:33 PM Chris Wilson <chris@...> wrote: 10 January 2022 Only daylight hours, AFAIK, and? MUCH louder on a big (about 380 feet in circumference) horizontal quad wire loop that along one leg runs parallel to overhead phone and mains LV power lines. On my wide aperture Wellbrook loop about 70 yards away from the overhead lines and 20 yards away from the horizontal loop it's much reduced. The noise lasts 2 minutes or so mainly, disappears and comes back? few minutes later. (Usually, but fairly random other times). It's not emanating? from my house, it's there running batteries and all power off. If you can spare the time to look any ideas are much appreciated, it's a well defined pattern some may have come across before, thanks. File names should be pretty self explanatory -- Best regards, ?Chris? ? ? ? ? ? ? ? ? ? ? ? ? ? mailto:chris@... -- Dave - W?LEV Just Let Darwin Work
Tomasz Lemiech #15848 On Tue, Jan 11, 2022 at 1:35 AM W0LEV <davearea51a@...> wrote: I can not look at the link.? My PC cautions of a possible security risk.? No risk in there, just a zip with a bunch of JPEG images inside. The warning probably comes from the fact that the link is http:// and not https:// (that is, the file is sent to the browser unencrypted, which is not a huge deal in this case). If clicking the link directly does not work, then copy it to the browser address bar. (Sorry for OT) -- Tomasz Lemiech
Sean - G4UCJ All Messages By This Member #15850 开云体育 Hi Chris, That is a washing machine making that pattern – it’s exactly the same as ours, which is an Indesit so it’s probably the same across the other makes that employ the same motor system. I spoke to an engineer about it and he said that it was something to do with the motor or the way they had it configured. Ferrites on the mains lead did nothing for it. If it is a big issue, you may have to resort to putting some filtering components around the motor area. Not my area of expertise so can’t make a suggestion there. ? 73, Sean G4UCJ ? toggle quoted message Show quoted text From: [email protected] [mailto:[email protected]] On Behalf Of W0LEV Sent: 11 January 2022 00:36 To: [email protected] Subject: Re: [loopantennas] Anyone perhaps able to ID this noise source on top band please? ? I can not look at the link.? My PC cautions of a possible security risk.?? ? Dave - W?LEV ? On Mon, Jan 10, 2022 at 1:33 PM Chris Wilson <chris@...> wrote: 10 January 2022 Only daylight hours, AFAIK, and? MUCH louder on a big (about 380 feet in circumference) horizontal quad wire loop that along one leg runs parallel to overhead phone and mains LV power lines. On my wide aperture Wellbrook loop about 70 yards away from the overhead lines and 20 yards away from the horizontal loop it's much reduced. The noise lasts 2 minutes or so mainly, disappears and comes back? few minutes later. (Usually, but fairly random other times). It's not emanating? from my house, it's there running batteries and all power off. If you can spare the time to look any ideas are much appreciated, it's a well defined pattern some may have come across before, thanks. File names should be pretty self explanatory -- Best regards, ?Chris? ? ? ? ? ? ? ? ? ? ? ? ? ? mailto:chris@... -- Dave - W?LEV *Just Let Darwin Work* ?
Martin - Southwest UK All Messages By This Member #15851 On Tue, Jan 11, 2022 at 09:12 AM, Sean - G4UCJ wrote: it’s probably the same across the other makes that employ the same motor system. Unfortunately a lot of machines and appliances these days are changing over from using traditional AC induction motors (which were relatively RF quiet) to variable speed DC motors, which require an electronically derived multi-phase drive. This can be produced by an external invertor circuit or in some cases it is actually built into the motor assembly, and is often sealed with no way of being opened for modification. I had a problem with noise being radiated from two fans in an air sourced heat pump, which used motors with integral invertors. The only solution was to properly bond the metal case sections on the external unit, and fit some galvanised wire mesh across the large fan apertures which were only protected by plastic guards and provided no RF screening. Regards, Martin
Jan Boutsen All Messages By This Member #15852 开云体育 Hello all, This paper, with help of radioamateurs might be of interest: ? Jan ON4MMW toggle quoted message Show quoted text From: [email protected] <[email protected]> On Behalf Of Sean - G4UCJ Sent: Tuesday, January 11, 2022 9:12 AM To: [email protected] Subject: Re: [loopantennas] Anyone perhaps able to ID this noise source on top band please? ? Hi Chris, That is a washing machine making that pattern – it’s exactly the same as ours, which is an Indesit so it’s probably the same across the other makes that employ the same motor system. I spoke to an engineer about it and he said that it was something to do with the motor or the way they had it configured. Ferrites on the mains lead did nothing for it. If it is a big issue, you may have to resort to putting some filtering components around the motor area. Not my area of expertise so can’t make a suggestion there. ? 73, Sean G4UCJ ? From: [email protected] [mailto:[email protected]] On Behalf Of W0LEV Sent: 11 January 2022 00:36 To: [email protected] Subject: Re: [loopantennas] Anyone perhaps able to ID this noise source on top band please? ? I can not look at the link.? My PC cautions of a possible security risk.?? ? Dave - W?LEV ? On Mon, Jan 10, 2022 at 1:33 PM Chris Wilson <chris@...> wrote: 10 January 2022 Only daylight hours, AFAIK, and? MUCH louder on a big (about 380 feet in circumference) horizontal quad wire loop that along one leg runs parallel to overhead phone and mains LV power lines. On my wide aperture Wellbrook loop about 70 yards away from the overhead lines and 20 yards away from the horizontal loop it's much reduced. The noise lasts 2 minutes or so mainly, disappears and comes back? few minutes later. (Usually, but fairly random other times). It's not emanating? from my house, it's there running batteries and all power off. If you can spare the time to look any ideas are much appreciated, it's a well defined pattern some may have come across before, thanks. File names should be pretty self explanatory -- Best regards, ?Chris? ? ? ? ? ? ? ? ? ? ? ? ? ? mailto:chris@... -- Dave - W?LEV *Just Let Darwin Work* ?
Steven Greenfield AE7HD All Messages By This Member #15854 Please don't forget to trim your replies. -- Steve Greenfield AE7HD
Chris Wilson All Messages By This Member #15855 Hello Sean, Tuesday, January 11, 2022 Thanks sean and everyone who has replied so far. I am sceptical as to it being a washing machine as it has been present for eight hours today, with no more than ten minutes between sequences. Now, my wife knows how to keep Scottish Power happy and in profit, but eight hours plus washing? It's definitely not from here, I turned the mains off again and no change, and for sure the Wellbrook some way back in the woods hears it far less than the horizontal quad loop that runs nearest overhead 240 V mains and telephone wires, and two other properties. There is a big chicken shed fairly near, probably half a million birds, and avian flu is also local, I wonder if it's that and they are running the cooling blowers more to achieve good airflow? I wouldn't have thought big blowers would cycle on and off so frequently though... Next door but one do, probably 70 yards away do have solar panels on the roof of a big stables building, do solar panels and their associated "stuff" shut down at night, as I don't believe I ever see this noise during the hours of darkness? Today has been very overcast, yet one of the worst times for continuous noise on top band I can recall seeing. I'll investigate a portable radio, it needs to hear 160 meters, sod's law says this noise ius bang in the middle of the band, any recommendations please? Thanks for the ideas. Best regards, Chris mailto:chris@... SG> Hi Chris, SG> That is a washing machine making that pattern – it’s exactly the SG> same as ours, which is an Indesit so it’s probably the same across SG> the other makes that employ the same motor system. I spoke to an SG> engineer about it and he said that it was something to do with the SG> motor or the way they had it configured. Ferrites on the mains SG> lead did nothing for it. If it is a big issue, you may have to SG> resort to putting some filtering components around the motor area. SG> Not my area of expertise so can’t make a suggestion there. SG> SG> 73, Sean G4UCJ SG> SG> From: [email protected] [mailto:[email protected]] On Behalf Of W0LEV SG> Sent: 11 January 2022 00:36 SG> To: [email protected] SG> Subject: Re: [loopantennas] Anyone perhaps able to ID this noise source on top band please? SG> SG> I can not look at the link. My PC cautions of a possible security risk. SG> SG> Dave - W?LEV SG> SG> On Mon, Jan 10, 2022 at 1:33 PM Chris Wilson <chris@...> wrote: SG> 10 January 2022 SG> Only daylight hours, AFAIK, and MUCH louder on a big (about 380 SG> feet in circumference) horizontal quad wire loop that along one SG> leg runs parallel to overhead phone and mains LV power lines. SG> On my wide aperture Wellbrook loop about 70 yards away from the SG> overhead lines and 20 yards away from the horizontal loop it's SG> much reduced. The noise lasts 2 minutes or so mainly, disappears SG> and comes back few minutes later. (Usually, but fairly random SG> other times). It's not emanating from my house, it's there SG> running batteries and all power off. If you can spare the time to SG> look any ideas are much appreciated, it's a well defined pattern SG> some may have come across before, thanks. SG> File names should be pretty self explanatory SG> SG> -- SG> Best regards, SG> Chris mailto:chris@...
Simon All Messages By This Member #15859 Hi Chris You may never find it, or if you do cure it..solar cells on roof? possibly, no chance there of course of asking neighbours to remove it.. My i suggest buying/ building a noise cancellation device/ phaser..even if just to you do cure the noise ( good luck with that if not on your property!) I use 2 here..( london) without them more often or not 160m would be a waste of time.. Also much as you not want to use a 1m loop but it can null out the noise IF from a single point.. Simon g0zen
@tigersaw All Messages By This Member #15902 I replied earlier about trying a portable radio tuned anywhere on MW band, thats how I located my interference. Hopefully this link to a video of it starting up on the SDR will work: Is it similar?
Chris Wilson All Messages By This Member #15904 Hello Friday, January 14, 2022 No, unfortunately it's not like that, I haven't had chance to do much more since, but do suspect it's something related to sunlight levels, it disappears as the light fades. Thanks for the link though, investigations continue as work allows. Best regards, Chris mailto:chris@... tgc> I replied earlier about trying a portable radio tuned anywhere tgc> on MW band, thats how I located my interference. tgc> Hopefully this link to a video of it starting up on the SDR will work: tgc> tgc> Is it similar? _._,_._,_
Steven Greenfield AE7HD All Messages By This Member #15906 ?but do suspect it's something related to sunlight levels, it disappears as the light fades Well, that sure sounds like it may have something to do with solar panels nearby. Could even be those annoying little solar walkway lights. -- Steve Greenfield AE7HD

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