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Author Topic: 11 meters mystery - solved.  (Read 2327 times)

Offline 45auto

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11 meters mystery - solved.
« on: March 03, 2020, 1406 UTC »
  A few months ago, I reported a strange "windy" sound upon 11 meters freeband. 
  You kind gentlemen referred me to the Fish Hook Welder.
   I grew angry by the arrogant disregard of this welding device vs our radio band.
   -  - 
   Last night,  my wife and I were going to bed, enabling our bedside clock radio MP3 player.
   "SWISSSHH...!" the Fish Hook Welder blared over channel 42.   
   
   Long story short, the damn Made in China clock radio emits a powerful Spurrious emission IDENTICAL.
   
     Damn, mystery solved!   

      45auto, Western NY

Offline Josh

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Re: 11 meters mystery - solved.
« Reply #1 on: March 03, 2020, 1848 UTC »
I think what happens is they steal a design from somewhere, then start removing parts till it either stops working or catches fire, then go back one step and fire up the production line. So you can be sure any rfi filtration will be absent.
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Offline nickcarr3151

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Re: 11 meters mystery - solved.
« Reply #2 on: March 03, 2020, 2024 UTC »
Frankly, those are easy culprits to find.  It's the damn powerline noise that drives me up the wall.  Bzzzzzzzzzzz!  Across most of HF.  When we have high winds, it knocks the branches all around.  The trees that have yet to be trimmed by our utility company end up getting into these lines and causing sparks, etc. 

A few years back I noticed that when the noise got high that meant a transformer was about to blow.  Sadly, that logic didn't hold water after the first few times it happened.
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Offline Josh

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Re: 11 meters mystery - solved.
« Reply #3 on: March 03, 2020, 2027 UTC »
If you live near streetlights, you can expect some evil on hf and ambc when the starters get bad. You'll note a light has problems starting when it should come on, is on during the day, ect, the bad one around here is around S8 and covers hf. Amazingly the nb on the pro2 and the rest of the rigs here makes it go away.
We do not encourage any radio operations contrary to regulations.

Offline nickcarr3151

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Re: 11 meters mystery - solved.
« Reply #4 on: March 03, 2020, 2037 UTC »
Thankfully we don't have the streetlight issues here.  I know SoCal switched to their 'green' version many years ago and those definitely caused some issues.  I've had all kind of RFI here at this QTH -- from electric pet fences, powerline spark gap, cable tv amps, touch lamps and PLN crap. 
Perseus SDR + Wellbrook ALA100LN (60m loop), Wellbrook 1530S+
ICOM 7000 + Zero-Five 10/40 GP Vertical
Xiegu G90
Motorola XPR/XTS Portables, Uniden scanners, Whistler Scanners
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Offline ChrisSmolinski

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Re: 11 meters mystery - solved.
« Reply #5 on: March 04, 2020, 1141 UTC »
I think what happens is they steal a design from somewhere, then start removing parts till it either stops working or catches fire, then go back one step and fire up the production line. So you can be sure any rfi filtration will be absent.

Sometimes they don't even go back the one step.
Chris Smolinski
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