For the last few months, normally in the afternoon, but not everyday, I get a dreadful noise appearing between 14.281-14.2866.
At its strongest (-92dBM)is on 14.285100. The source is not the equipment here as I have checked. Its sounds like a pulsating mains hum. Today it was going between 1500-1630Z and as before suddenly stops.
Has anyone in the UK had a similar experience?
Does anyone know what sort of equipment would ‘land’ a harmonic on this frequency?
I find the FT817 with the 6 metres rubber duck is great for this job - I know exactly where in the neighbours house his plasma TV lives - fortunately they don’t watch a lot of TV except for the sport programs - which, of course, are mainly of a weekend!
Hello Brian, just been testing the sensitivity of the Yup scanner - with the standard antenna it is quite deaf. I will have to use the FT897D.
I wouldn’t mind if I was urban but I live in a rural area, on a hill, overlooking a valley. The batteries for the 897 are all charged up - the other day I cut off the power supply to the house to see if there was something in the house generating the noise and listened on the 897 ~ so ready to go.
About 6 years ago, I tracked down the source of a terrible noise (24/7) to the power supply of a cheap supermarket TV set two doors down the road. The neighbour would not allow me anywhere near his set and he and his wife have been “not speaking” to me ever since! The noise ceased after 4 years when his set finally blew up and he bought a new one.
A good question and one I have thought about. Right now I will not do anything but just locate. If the noise becomes 24/7 then I will have to knock on a door and hope that I can persuade the owner that their equipment would work SO much better with a few mods
A few years ago I had terrible QRM across most of the HF spectrum but peaking around 5MHz. As Brian mentioned I used my 817 with it’s 6M helical aerial and tracked it down to a neighbour’s kid’s fridge which he keep in his room. It appeared the noise was being induced back into the mains wiring which was acting as a pretty good radiator.
Having pointed this out to the neighbour I said that they didn’t have to do anything as I would come up with the solution. I ordered a couple of mains filters from RS and fitted them into single 13A MK Type holders (about 50mm depth)with extension lead (1M)and plug. I gave one to the neighbour to fit between the wall socket and the fridge. Problem solved.
A few months later the neighbour gave me the the lead back, stating that it was no longer required as like Walt’s problem - the fridge had given-up-the-ghost!
Todate I haven’t had to use either of the leads, but there there just in case?
Now how to get rid of data noise - pops, purrs, squeaks, wow-wows, meows etc! Oops now where did I leave the cat?
PS: The 817 is also great for tracking down car bourne noise and where it is eminating from. Now solving it in modern cars - that’s another problem - hi!
In reply to F5VGL:
The Radio Astronomy is a “listening” (passive) service; it can’t produce interference. If uses or not the 20m band doesn’t make any difference for us. We are an “active” service (we are transmitting). Indeed, the astronomy band is lower then amateur radio band because there are the signals of interest for them.
But, mostly probable the noise in discussion come not from other planets, but from somewhere in neighborhood.
73 de Dan
The source of the noise 14.285 +/- was from a neighbour located about 50 metres from my SteppIR vertical. The vertical is about another 50 metres to the shack. My neighbour Richard is a retired banker and is married to a woman from Hong Kong. They spend 4 out of 12 months in HK. They came back 3 months ago. His wife bought an electronic organ (China) and has a practice every afternoon. When I first started talking to him about “noise” he thought I was talking about her playing! We had a chat over a cup of tea. Richard did not quite understand what I was on about. Hopefully she will get bored and sell the organ along with its ( I suspect) RF generating power supply unit. So I have to live with it until then…