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Using an external keyer with the 6400M

I want to use an external keyer for two reasons; to 'solve' the awful CW timing issue and to be able to adjust weight which Flex does not allow. If I use pin 4 on the accessory connector for the keyer input will the CW timing issue be taken care of? Other suggestions? Thanks! 73.


  • K0FLY
    K0FLY Member ✭✭✭


    I have always used an external keyer with my Flex radios, I didn't realize there were CW timing issues. I plug it into the Flex key jack (tip/ring), turn off iambic in the menu, works great. I would expect pin four input to work the same.

    Gayle K0FLY

    WØYVA Member ✭✭

    Okay, thanks, Gayle! Tip and ring, is that right?

    Out of curiosity what keyer do you use?

  • K0FLY
    K0FLY Member ✭✭✭

    Yes tip and sleeve.

    ______________________________________from Flex Hardware manual________________________________________


    For CW operation, the ⅛ inch (3.5mm) TRS KEY connector accepts a TRS plug for operating a keyer with paddles or a straight key.

    When Connecting a CW straight key, a TRS plug must be used for proper connectivity to the radio. Connect the key to the Tip and Sleeve, leave the Ring unconnected.


    I use the Cedar Rapids keyer designed by Bud Southard and Jeff Russell. The keyer kit was manufactured and distributed by Bob W9KNI (Logi kit), its now sold by Ham Supply. The paddles and enclosure were designed by Dave W0SS (about 15 were made). Dave is the engineer of record on the 75S-1, I'm sure you have one.


    Gayle K0FLY

    WØYVA Member ✭✭

    Ah, yes, tip and sleeve! That makes more sense. I also found this in the manual which I should have more carefully reviewed.

    Yes, lots of Collins stuff here. HI

    73, Bob


    Personal site: isquare.com

  • K0FLY
    K0FLY Member ✭✭✭


    I meant tip and sleeve and wrote tip and ring. My bad.

    73 stay safe


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