Noise

  • 1
  • Question
  • Updated 7 months ago
Any Ideas as to what this noise might be. Starts at 160m and all the way up to 80m

Photo of WW1SS - Steve

WW1SS - Steve

  • 641 Posts
  • 195 Reply Likes

Posted 7 months ago

  • 1
Photo of Frank  WA3NHK

Frank WA3NHK

  • 67 Posts
  • 13 Reply Likes
So it appears to be repeating every 200 kHz or so.  Is it present 24x7?  If you go wideband does its amplitude appear to decrease linearly with frequency?
Photo of F6EJU

F6EJU

  • 16 Posts
  • 2 Reply Likes
Have such signals about all the 200Khz on 21 Mhz 28 Mhz   that is my dear next door using PLC for their computers and TV home net work
Photo of F6EJU

F6EJU

  • 16 Posts
  • 2 Reply Likes
Sorry  its  spaced by 15 Khz and  cover the 21 and 28 Mhz bands  and not spaced by 200 Khz.
Photo of WW1SS - Steve

WW1SS - Steve

  • 641 Posts
  • 195 Reply Likes
Here is what it looks like wide bsnd. There 24/7
Photo of WW1SS - Steve

WW1SS - Steve

  • 641 Posts
  • 195 Reply Likes
Another image.
Photo of Frank  WA3NHK

Frank WA3NHK

  • 67 Posts
  • 13 Reply Likes
That’s a really high background noise level. It looks like it’s around -90. And it appears to be associated with the peaks. Can you contact someone a few miles away from you and see if they’re seeing this as well? I’d like to know how localized it is.
Photo of F6EJU

F6EJU

  • 16 Posts
  • 2 Reply Likes
Photo of F6EJU

F6EJU

  • 16 Posts
  • 2 Reply Likes
That is the QRM from PLC we have in FR every where people use it for home TV and PC  home net.
People have concerns about cell phone but not for these electromagnetic waves QRM generator that have invaded their home
Photo of N9VC

N9VC

  • 125 Posts
  • 34 Reply Likes
Hi Steve,

Did the noise just start or has it been around quite
a while? When we have encountered noises in the past,
the first thing we think is, what changed, what have
we added to the home.
Have you shut off circuit breakers trying to see if
it disappears? That is an easy way to isolate the
noise if it is local in your home. If nothing else,
that eliminates the home as a problem.
If it is not in your home, maybe a noise canceller
such as a Timewave ANC-4 or a DX Engineering NCC-2
which is what we have here. That stops it from getting
in the radio, which is the ideal way to make better
reception.
We had a 30 over noise last year that we could not
locate and also had no pattern or duration that
could be tracked. It was not power line noise, but
the NCC-2 enabled us to reduce it to just about
nothing. The noise has been gone, for months now,
but we are ready should it ever rear its ugly head.

73, Jim N9VC
Photo of WW1SS - Steve

WW1SS - Steve

  • 641 Posts
  • 195 Reply Likes
It started about 2 weeks ago. Nothing here in the house and no changes. Only thing I can think of is that we have new people that bought the house next door and something they have plugged in is causing it. They are only here on the weekends so I will ask them when they get here this weekend. My dipole is setup on the property line between our 2 houses
Photo of F6EJU

F6EJU

  • 16 Posts
  • 2 Reply Likes
Steve
Could be  a power supplies

People are also friends and nextdoor by here.
I Do not want to make trouble between us.
The cable in ethernet could be a solution but difficult in villa having two floors
i have found the root of the QRM using a portable TRX.
When they stop their PLC  I have no QRM.
 I remember the years when we had a simple Heatkit HW101 and no QRm... hi
73
jean claude F6eju