20m Noise Images

  • 2
  • Idea
  • Updated 4 years ago
A quick image to show how noise levels can change when the neighbors wake up. The "quiet" frame is early in the morning and shows a nice, clean (and hard-won) environment. Once the day begins, and the neighbor's (three houses and a street away) pool pump comes on, well... see for yourself. Moral of the story - no matter how clean you make your installation, there's a LOT of noise out there...

Yes, same antenna, same settings exactly. 

 
Photo of George Molnar, KF2T

George Molnar, KF2T, Elmer

  • 1561 Posts
  • 552 Reply Likes

Posted 4 years ago

  • 2
Photo of Rob N4GA

Rob N4GA

  • 147 Posts
  • 25 Reply Likes
That's a shame isn't it?
Photo of KY6LA - Howard

KY6LA - Howard, Elmer

  • 3541 Posts
  • 1396 Reply Likes
Time for a visit from the Midnight Ferrite Patrol.
Photo of George Molnar, KF2T

George Molnar, KF2T, Elmer

  • 1561 Posts
  • 552 Reply Likes
Oh, I've dreamt of more than that...
Photo of KY6LA - Howard

KY6LA - Howard, Elmer

  • 3541 Posts
  • 1396 Reply Likes
The Pin Throughthe CB Coax Squad?
Photo of Rick Hadley - W0FG

Rick Hadley - W0FG

  • 579 Posts
  • 120 Reply Likes
Ahhh, that brings back memories...LOL!
Photo of Stu Phillips - K6TU

Stu Phillips - K6TU, Elmer

  • 642 Posts
  • 256 Reply Likes
My guess is the the pump controller is inadequately filtered and the RFI from the controller is back feeding into the power grid and then radiating.

I had a very similar issue with one of my neighbors about half a mile away that clobbered 160 totally and made a mess of 80m.

The variable speed controller module was an OEM unit that had been built into an "energy efficient" pool controller by a yet another company.  I pulled the manual for the module from the manufacturers web site and it explicitly said that for deployment in urban areas, additional filtering would be required.

But surprise!  There was NO filtering on the module at all - it was just fed AC (240v) and back fed via the pole-pig into the overhead wires.

Corcom makes a range of filters that should nail this - DigiKey sells the filters and they are around $100.  That said, I wouldn't touch the neighbors gear or even offer.  Too much liability and finger pointing opportunities.

Contact the FCC - it will take a while but they will act and it really helps if you can show them pictures like this and have identified the source.

If you are on good terms with the neighbor, you might advise them that this is their responsibility and they need to fix it - its ok to discuss how with their designated electrician although it may require significant effort to nail this even with a filter.  For example, the filter needs to be in a shielded box that is appropriately grounded, grounded conduit for the wiring etc.  The NEC has specs on how this is supposed to be done - but even good electricians can overlook things.

In my case, the property owner contacted their pool company who had installed the new "high tech" pool controller... they replaced the controller with a conventional unit at their expense after the neighbor was shown the FCC regulations...  I was fortunate - I didn't have to get the FCC involved.

YMMV... sorry.
Stu K6TU
Photo of George Molnar, KF2T

George Molnar, KF2T, Elmer

  • 1561 Posts
  • 552 Reply Likes
Stu, your story resonated with me on this one. I was able to DF the noise reasonably well, and now with aerial photos of everything under the sun, I could match where I heard noise coming from to what was in the backyard. Suburbia. Someday I'll escape...

Oh, I also have a variable speed pump. With a solid ground and a line filter. Nice and clean (now). Sad they don't come that way.
(Edited)
Photo of W5XZ - dan

W5XZ - dan

  • 564 Posts
  • 83 Reply Likes
nice screen shots, george; see almost the same thing here on 160 during 'prime time' in suburban Longview, Tx...chasing 3 new AF's on 160m...E30, 9Q, 7P8...