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I have a long delay (~10sec) after Tx before switching back to RX when using FLDIGI

Hello, i am F6AFU,

I am using a flexradio 6500. I have set up smartSDR and fldigi to communicate, but there is a long delay after my TX were the radio does not switch back to Rx for around 10 seconds, while waiting after TX the waterfall is completely black. fldigi has stoped transmitting, but the radio is still in tX mode for 10 secondes before going back to Rx where it works nominally. We can't find any settings for this case.

Do you know something that could help us?


  • Martin AA6E
    Martin AA6E Member ✭✭✭

    Perhaps you have the Flex set up for VOX T/R control with a long delay? It is better to use direct CAT T/R control which should have minimal delay.

    73 Martin AA6E

  • Mike-VA3MW
    Mike-VA3MW Administrator, FlexRadio Employee, Community Manager, Super Elmer, Moderator admin

    What method are you using to put the radio into Transmit?

    • Vox?
    • CAT Command?
    • RS232/Serial level?

    Something from FLDigi is holding it up. I would recommend you use FLRig to control the radio if you can. It is part of FLDigi


  • Hello, thank you for your help. In fact, we are using VOX, and its parameters also impacted us, without it we can't manage to TX. We tried to find how to directly send via CAT command as you guys described without success. How can we do this? Thank you.
  • K0FLY
    K0FLY Member ✭✭✭

    There are several You Tube Videos showing FLDIGI, FLEX SSDR with DAX and CAT setup. Search YOU TUBE for FLDGI and FLEX 6000. Here is one by Mike VA3MW:

    Gayle K0FLY

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