Noise Ripples

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  • Problem
  • Updated 4 years ago

I have noise ripples that cross every band that I tune the Flex 6700 to. These are represented in the waterfall as swirls that go across at least half of the bandwidth that I am monitoring. They move from right to left in frequency. I can see them as amplitude wise as broadband noise that is just above the noise floor.

 Any idea what this?

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ka7gzr

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Posted 4 years ago

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Mickey N4MB

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Welcome to being able to see noise graphically! You're likely looking at one or more noise sources. You're going to need to troubleshoot the noise source.  Start by disconnecting the antenna to see if it goes away. If it does, there's a noise source nearby... maybe in your shack. Troubleshooting noise sources is beyond the scope of a message, but the ARRL noise page is a good place to start: http://www.arrl.org/radio-frequency-interference-rfi
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Paul Christensen, W9AC, Elmer

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Are you seeing the noise with the antenna(s) disconnected?  Please attach a screen capture.

Paul, W9AC

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ka7gzr

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Here is what I am seeing...
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Peter K1PGV, Elmer

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Hmmm... I used to see these "rolling humps" run through my panadapter all the time with my sdr-1000 and 1500.  I never knew what they were... I thought they had something to do with the radio or power supply or something.

Peter K1PGV
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Stan - VA7NF

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As previously stated, interesting what you see and probably can't hear as these are less that 1db above the noise level.

The "whistler" I mentioned above appears as a single, and louder, trace.  These are harmonically related to 50Khz and, if zoomed in, are probably modulated with 60hz harmonics.  That looks like a switching power supply or wall-wart.

Do you see at much lower frequencies?

Do you have a directional antenna (main or hand held) that will identify a direction or is it common mode that is reduced by ferrites at the 6000?


Stan

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Robert -- N5IKD, Elmer

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That is light compared to the issue I was having. Fortunately I was able to narrow the problem down to the LED lighting in the bathroom. 

http://youtu.be/rDCXPNwajro

It is always best when you find the issue in your control. If my neighbors get LED lights I will have a problem.
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Stan - VA7NF

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AA0KM

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http://www.sigidwiki.com/wiki/Signal_Identification_Guide

Very interesting waterfall screen captures.They allow offers from users if you find anything interesting on your waterfall.

73 aa0km

(Edited)