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Where is the RF Preamp control or button on the 6400M?


I am trying to adjust my RF Preamp, but don't know where to look where the control or switch to do that. Help!

Mark Griffin, KB3Z

Best Answer


  • Trucker
    Trucker Member ✭✭✭

    On the M model radios touch the Antenna indicator on the Slice flag. You will get a pop-up window showing different antenna settings. There is a slider near the top of the window that allows you to set the Gain from -16db ( all the way to the left) to + 34db)

    You should see an indication of the gain in white letters in the upper right corner of the spectrum display.



    download the manual from Flex Radio's website. It covers both the 6400M and the 6600M.

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