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Newbie question on waterfall view.

adrian miura
adrian miura Member
edited June 2020 in SmartSDR for Windows
I’m just received my 6300 and  loving all the information it present me. However being new to this view is it normal to see diagonal traces on the waterfall view? What would cause the movement?

Completed · Last Updated


  • KY6LA_Howard
    KY6LA_Howard La Jolla, CA. Paris and Sablet FranceMember ✭✭✭
    edited January 2017
    Looks like u got lots of local noise and/or internal noise in ur station Suggest you read. My paper on how to build a quiet station https://www.dropbox.com/s/kffp92esffo3zy5/How to Build a Quiet Station V2.pdf?dl=0
  • George KF2T
    George KF2T Member ✭✭✭
    edited February 2019
    Looks like really bad local RFI. So sorry! Hope it's relatively easy to track down.
  • Reg
    Reg Member ✭✭
    edited March 2017


    It is a diagonal trace because the source of your noise is drifting in frequency.  We see that the noise floor to the right of your receive frequency is lower than the noise floor to the left.

    If you set your receive mode to CW, SSB, and AM, respectively, do you hear anything?  Sometimes the changing energy level that raises and lowers the noise floor does not create noise that the receiver hears.  From the looks of the irregular trace it might sound like a buzz saw.

    Your overall noise floor on 20 meters seems to be very high.  I am accustomed to seeing -110 when near a city and even lower in a very quiet location.  Your noise floor appears to vary in the mid -90's.

    This is an opportunity to use your 6300 as a test instrument.  If you widen the receiver as wide as it will go you will probably see a recurring pattern of rising and falling energy.  Document the periodicity of the peaks.  Many of use on the Community had a lot of cumulative experience in tracking down noise.  KY6LA did an excellent job of documenting avoidance techniques.  If you document the entire spectrum that your 6300 covers that will give us a chance to identify the likely culprits.  It is a lot easier to search for a noise source if the emitter is narrowed down to one or a few likely sources.

    Let us know what you see and hear and we'll try to assist further.


  • adrian miura
    adrian miura Member
    edited March 2016
    Thanks guys this is great info. the noise floor drops considerably in the morning before 1000h MT (-110db) I have attached another diagonal waterfall. Yes listening to it you definitely hear the “buzz saw” modulate as it tracks from a higher frequency to a lower one. Any ideas of what would cause this type of noise?The second image is the zoomed out view.


  • adrian miura
    adrian miura Member
    edited March 2016
    have downloaded your whitepaper and working through the noise reduction techniques.
  • KY6LA_Howard
    KY6LA_Howard La Jolla, CA. Paris and Sablet FranceMember ✭✭✭
    edited December 2014
    Looks like someone has a Plasma TV broadcasting noise...

    One of the benefits of a broad spectrum radio like the 6000 series is that you see EVERYTHING on the air..

    One of the issues of the 6000 Series ... is that you now can SEE EVERYTHING TOO... so "****" which did not bother you on a legacy radio albeit you heard it whipping out signals becomes a big bother because you can finally see how really bad it is...

    Good luck hunting down the RFI...
  • Ken - NM9P
    Ken - NM9P Member ✭✭
    edited June 2020
    We have some hockey puck under counter halogen lights that make traces like this when they are turned on. I ask my wife to unplug them whenever they are not absolutely needed.

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