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FT8 Transmitted Signal in Panadapter

Neil D Friedman N3DFNeil D Friedman N3DF Member ✭✭
I have a 6600M and am new to FT8.  What should my transmitted signal (35 watts) look like in the slice panadapter?  Bandwidth is set to 5 kHz.  Thank you.


  • Larry _ W8LLLLarry _ W8LLL Member ✭✭
    edited July 2018
    This is what mine looks like with 35 watts.

  • Tim - W4TMETim - W4TME Administrator, FlexRadio Employee admin
    edited July 2018
    Your spectrum is probably fine.  The one above is.  Notice the symmetry of it which is indicative of a properly generated signal.

    You have to ignore the signals assumed to be spurious emissions.  When we show the transmitted spectrum, we use the receiver in the radio to show the actual transmitted RF coming from the DAC and that will have harmonic components of the primary signal.  Also, some of these "signals" are harmonics from the DSP in WSJT-X when it generates the FT8 (or whatever mode you are running) tones.  What is actually transmitted as RF are only the signals inside the TX filter.  And also pay attention to the magnitude of the signals too, most of them are -125 dB down and almost 90 dBc, more than twice the FCC requirement for spurious emissions (but that is moot since they are not being transmitted as RF).

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