Noise


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If you suffer a Noise problem, don’t leave it, get active and try and find what is causing it all, it could be something really simple and easy to resolve and you could actually be causing it yourself, or it could be something that could have serious consequences and put lives at risk.

If you are not sure how to go about it then get on the RSGB website, you may find your answers their..


Noise Problems 2018

Greetings everyone,

Since my last nightmare, I have had this other intermittent noise for some time.

On all bands including MW, the same nasty old noise sounding like an electric razor.

I have pretty much ignored it, but recently it’s become a problem, so i decided on finding it.

I knew it had to be something in my neighbours log cabin, which sits at the end of his garden next to mine, every time he leaves the power on at night i get wiped out.

Today I asked him if we could find it as i was certain it was coming from his cabin, my hand held was telling me so, he agreed and i took my hand held in with me with trusty loop antenna, and immediately saw a perspex led etched name plate hanging to the left of his cabin on the wall, the item was plugged into the mains switched on but also had a on/off switch half way up the cable and a moulded UK plug and the item was in standby mode or off.

I was using my hand held scanner on 1.930 mhz in “AM” mode, all you could hear was a nasty buzzing when i turned the light on using the switch on the supplied cable, it changed frequency of the buzzing but was even louder, the RF noise covered all frequencies including MW and right up to 50 odd meg’s, when it was switched off at the mains it was silent, my neighbour was stunned and I then went into teacher mode to explain it all, i am lucky he was very accommodating about it all.

I asked if he minded if i could see if i could make it quite using ferrite clamps, and he agreed, so i took it away to the workshop and did some testing, ferrite’s made no difference at all, i took the on/off switch apart and found a circuit board with no rf shielding and it was in a plastic case, no CE marks at all on any of it.

It turns a normal flat signal zero to 9 plus db, a proper jamming device indeed and could be heard on the scanner over 80 foot away, which gave and RF signal of about 3 db at 80 foot, the actual name plate was 3 foot away from the main antenna cable on our 5 way switch. and why it was so devastating being so close.

I then took away the power switch with its jamming device attached and added a 12 volt cable to it with an on off switch and supplied a 17ah battery.

All works a treat, Dave my neighbour is happy he can now hang his name plate where he wanted too, as the old mains power cable was very short and restrictive.

So, it’s a result for all.

Supplied below is some pictures of the actual board with the transformer on it and the plastic case, it came with a power cable, and the led name plate.

My Neighbors LED Sign
Stepdown transformer from 240 to 12v, very noisy, bloody dangerous.

 

This is what it was housed in, even with the switch off this device creates terrible RFI

Please think before you buy, the plug on this item has no fuse, its dangerous, how can it be sold, i hear? because its from Malaysia and sold on ebay and amazon and bypasses the EU regs, however, the minute you plug it in, your are then in full breach of the regulations, plus the fire hazards they bring.

If your going to buy one of these, then please get a 12 volt one and power it from a good power supply that don’t cause RFI or power it from a battery.

Over the moon we got this sorted..

Happy Days..

de Kev, 2E0WCK.. 73 [​IMG]

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Noise problems from 2016

Those of you that know me understand the noise problems I suffer.

I have in the last 2 years studying this problem as well as studying all the law around this and also how difficult it can be to resolve with the current legislation the way it is.

plot_1_40m_noFilter_7100mhz

All the noise seems to stem from the buildings lights causing very loud and dirty buzzing the main lights in situ are are Energy Saving CFL type, I have no other idea what they are, I am bound to a tenancy agreement, so I cannot take off the covers to look.

I will post up more details of all of this at a later date, with video footage and well as audio recordings, pictures and so on.


40 Meter noise coming from switch mode chargers trying to charge a dead battery
40 Meter noise coming from switch mode chargers trying to charge a dead battery

Please find a Screen Shot taken from DL4YHF’s Spectrum Lab (Audio Signal Analyser)

This software is absolutely superb & Free, which makes it even better.

My system Radio is interfaced using ZLP Electronics DigiMaster Pro3,

I can then run multiple audio programs at the same time including Ham Radio Deluxe and all its bells and whistles as well as Spectrum Labs.

This has helped me understand the Noise problem much better, using the 3d mode in Spectrum Labs really does show a much bigger picture visually than you get with just a standard Spectrum Scope.

plot_1_40m_7150mhz_vrf108_DNR06_Width_240_19022016_soundcard set to 22khz
plot_1_40m_7150mhz_vrf108_DNR06_Width_240_19022016_soundcard set to 22khz

This picture tells the story..

This Picture Represents the Noise from a Crescendo of 30 Energy Saving CFL Lights, this is the 40 meter band

The High Peaks in the 3D Plot show the lights spitting out RF every 12-13 seconds and it lifts the noise floor about 9db in winter time, and 7-8 db in summertime, even with this radio Yaesu FTDX5000MP and all its filtering capabilities just cannot knock out this noise.

I have even pulled back one of the legs from my 80 meter doublet antenna so it is further away from the noise source, but that only reduces it a very small amount, it completely wipes everything out

Radio Used for Tests:,

Yaesu FTDX5000MP with DMU-2000
Yaesu FTDX5000MP with DMU-2000

Yaesu FTDX5000MP with DMU-2000 Data Management Unit

7.150 Megahertz

2.4k Filter

DNR 06

Shift 0 Hz

VRF 108 (Variable RF Filter, The VRF feature allows you to engage a narrowband-pass “preselector”)  filter into the receivers RF circuit path. The added selectivity can be a tremendous help in minimizing potential interference from strong out-of-band signals, especially in a multi-transmitter operating environment.

Not every radio has this ability, most do not, so we are very lucky, when we tested this noise outside running on battery power using our Yaesu 857d, which is a standard portable all band all mode radio, with very little bells and whistles, it was basically useless, if this was the only radio we had, then our hobby would be over living here with this noise.

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Below is one of the Offending Lighting Units

The good news is, I have Dr David Lauder Coming along with some test gear, just to make sure it is these lights and that there is nothing else I have missed, we shall see what we find out, I will let you all know..

D Fluorescent Light,


We now know for sure what the problem is, as Dr David Lauder came around and spent quite a few hours here til almost midnight doing his survey and taking measurements, it does appear to be the Backup Emergency Batteries in these lights as above, I did mention this to the main engineer from the housing over a year ago, at the time he told me “nothing has been serviced for years” my brain said to me “No Shit Sherlock”

I mentioned to the housings engineer that the switch mode unit that charges the batteries will be constantly trying to charge dead batteries and would definitely be causing all this, but alas it went over his head, I had no way of testing this until Dr David Lauder came along, and at the time, I had no idea when that would be, was it the lamps themselves or the dead batteries?

Not only this, when the Engineer from the housing turned everything off, the emergency lighting went off after 30 seconds and stayed off, which meant that the building here had no working emergency lighting system, which effected 8 sets of residents here, and the other 4 buildings managed in the road by the same housing association, the emergency lighting system on them buildings would of most likely failed, this effected 40 sets of residents in total, my noise tests on each building told me all the emergency batteries had gone due to the noise levels coming from them, I mentioned this to the chap from the housing at the time, he just ignored me.

Now we have actual proof of this.

David is going to be writing up a couple of reports and I will keep you all informed when I know more..

Well done to Dr David Lauder for his visit, it was illuminating.. Thank you very much indeed for your time and trouble, it is most appreciated someone is championing the bit for us.

Thank you also to Ken Underwood G3SDW at the EMC Department of the RSGB, Ken, you da man! he is one man that kept me on it, even though at various stages I just wanted to throw the towel in.

A little about Marshall Amps and Ken Underwood


What next?, well, a while back I called the housing and after a good 15 minutes wait I spoke to a different electrical engineer who was brave enough to talk to me, I mentioned the emergency lighting , in fact I had to start again from scratch as I always did with the housing, don’t matter who you talked too, people just did not want to take responsibility to talk with me about it, but this chap did, he told me it was being taken seriously and they are on it, I did mention to him as I did with others, that we had no emergency lighting, and that a plan has been put into place to go direct to the managing director of the housing as it should not of taken me nearly two years to sort all this out, I also mentioned to them we had Dr David Lauder coming along to do an independent survey for Ofcom,

We have been consumed by this for the last 2 plus years, pretty much almost ruined me for the hobby due to the amount of obstacles we have had to face dealing with all this.

A few weeks later I noticed some paperwork in the foyer of the building, plus the lights was on 24/7 again, the paperwork showed the housing had actually contracted a company in, at last they sent out a contractor to deal with this..

I then contacted this contractor direct.

I will update the outcome soon.

The long and short of it is this;

We now have no RFI coming from the building lighting system during the day, horah! although we still do suffer the noise at night on the 40 meter band, 7.000 mhz to 7.200 mhz and 160 meters 1.800 mhz to 2.000 mhz is hard work.

Update: 09 04 2018

Yes it is now 2018 and its been a long time,

We got this all resolved, and was really lucky it was down to the “Emergency Building Lighting” which has more stringent regulations than say, Temporary Lighting or even Fixed Lighting, it really did pay to dig out all the legislation, which i might add was a total headache when your a full time carer for your disabled partner and being the chair at the same time of the local radio club.

The fact it was emergency lighting meant this,  I had all the power, yippee, and eventually, over a 6 month period, the entire building lighting system was upgraded to a new LED system and very pleased to say it did the job.

We only have around 4 more lights in the other buildings that have not yet been replaced, but they will be replaced when the units eventually fail, the noise from those lights are not bad to us at all due to the location of them, it turned out there was in total 48 lights, and the accumulation of that many with dead batteries over a distance of 100 meters was incredible, and why i had such a hard time finding it, an electrical engineer probably would of guessed it far sooner than I, but i’m am none of that, although I now have the skills to sniff this out and have that as a good bit of experience that i hope never to have to tackle again.

We do have a new building that’s gone up in the last 12 months, its a very large Lidl, and generates a very dirty noise floor, and we ain’t gonna do nothing about it, as its on the floor and not 9+db

It really did my head in having to do what i did, it was very stressful for me at times when i had to keep teaching people and explain things with legislation, rules and all sorts, Ken and the team from the RSGB Noise group really did help with my anxieties over this, we are very grateful for all the help we got, but you got to keep on, keeping on.

It’s sadly part of our hobby this noise crap, and we have three choices, we investigate and gain some superb knowledge, or we pack up and only use our kit portable or at a club, or even worse we sell the lot and go be a Lollypop man, hi hi.

As stressful as it can be, find that noise, make buy beg borrow but dont steal and get that knowledge or kit you need and get that help to track it down, we have an amazing community of knowledge to pull from like no other, so get on it, everyone will be willing to help, just ask!…

I am also aware that in some cases, just nothing can be done or resolved, I do have friends that have this problem, it don’t stop them going portable, we was close to selling up our kit, but so glad we never did.

Just don’t give up is the key..

If you need help to your problem, go to the RSGB Noise Forum, leave that message, get that knowledge.

Good Luck and 73.