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CW Only High VSWR 6600M

:( I searched and found no discussion with a similar title. I am new to Flex with a 6600M I bought used in December. I've used it as my CW/SSB radio since then. Suddenly, it has a high VSWR on CW only, even when connected to a dummy load.

Regardless of frequency, when I change the mode to anything BUT CW, activating the TUNE button works just fine. If I broaden the pan adapter, what appears to be second harmonic energy (40m TX watching on 20m) is the same for any mode. CW does not appear to be worse. I do not have a spectrum analyzer for accurate testing.

I restored factory defaults to no avail. Does anyone have suggestions before I submit a help ticket? While the radio still has more than a year of warranty, I am not enthused about shipping it to Austin.

Thanks and 73, Bill, K8TE


  • KD0RC
    KD0RC Broomfield, COMember ✭✭✭✭

    Hi Bill, Check to be sure that changing to CW does not change your transmit antenna (the red antenna indicator). If it does, try changing it back to whatever antenna you were expecting and try the tune button to see if that fixes the issue.

  • Bill Mader
    Bill Mader Member
    Same TX & RX antenna selections Len. Just for fun, I switched TX antennas. On CW, both selections failed (high VSWR). On the same frequency, switching to USB and pressing the TUNE button, both antennas (20m dipole on ANT1 and a dummy load on ANT2 had low VSWR.

    The problem is only on CW and disappears when switching to any of the other modes on the same frequency and antenna.

    73, Bill, K8TE
  • KD0RC
    KD0RC Broomfield, COMember ✭✭✭✭

    Sounds like it is time to submit a help ticket. I can't think of anything else that would cause this behavior.

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