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can a external mixer be connected to the 6400

keith hertzog
keith hertzog Member ✭✭

Best Answer

  • Craig_KØCF
    Craig_KØCF Member ✭✭✭
    Answer ✓

    From the Flex-6400 Hardware Reference:

    "7.5.2 Line Level

    There are a number of different definitions of “line level”. The audio input device in the FLEX-6400/FLEX-6600 series radios is designed for a “consumer line level” specification. This is defined as -10 dBV. If you plan to use “professional line level” devices to feed your radio, you will need to reduce the output level so that it does not exceed the -10 dBV level (-8 dBu). The hardware input will clip around 0 dBm (~-2.2dBV).


    The accessory connector is a high-density HD-15 female connector. There are a number of inputs and outputs on this connector.

    ! - This is the same type of connector used by VGA monitors. Do not connect to VGA monitors.

    Δ – All Accessory inputs are 3.3VDC MAX Input

    7.6.1 Pin 1: Line In

    This audio line input can be used to feed consumer level (-10dBV) audio into the transmitter. Refer to the SmartSDR documentation for information describing how to enable this input, and what configurations are available."

    In a word, yes you can feed in an external mixer. Just follow the Flex manuals, including SmartSDR manual for instructions on enabling the "line input".

    73, Craig KØCF


  • keith hertzog
    keith hertzog Member ✭✭

    Very helpful - I understand and thank you.

    73 n3svb

  • Randy KN4YBA
    Randy KN4YBA Member ✭✭

    Yes, my best option when running several radios and computers at the same time. I use two mixers, one for audio and the other for my mic input to each device.

    One Fosi Audio Amp and two Polk speakers driven by all the different mixer inputs for audio.



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