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Speaker Noise on Transmit


I just received my 6400 a few days ago and I'm getting it online. I did not know I need an external powered speaker so I attached a cheapo powered speaker from Amazon and it buzzes when transmitting FT-8 on 15m and some other bands. Some bands don't do this. Any ideas how to setup my speakers. I don't have a problem buying more expensive speakers if necessary. I'm just trying to get on the air right now.

Best Answer

  • KD0RC
    KD0RC Member, Super Elmer Moderator
    Answer ✓

    This sounds like RF getting into the speakers. I had the same problem with some cheap LabTech speakers. I put ferrites around the speaker leads and solved the problem.

    I have subsequently gotten a set of Creative T10 speakers, and they are interference free, even without the ferrites. They were around $42 from Amazon.


  • NB6Q
    NB6Q Member ✭✭

    Thank you. I'll try the ferrites first. I should have thought of that.

  • Pat_W5WTH
    Pat_W5WTH Member ✭✭

    FWIW..... I typically only use headphones, but I do have a high quality speaker with an on board rechargeable battery. The speaker has RFI from the Flex when running from mains power. The speaker has no RFI when running from its internal battery.

  • Steve KD2OM
    Steve KD2OM Member ✭✭

    What worked for me except on 6 meters was an isolation transformer. Amazon has them for about $11, it plugs right in between the radio and speakers. I am using Creative speakers which also are DC powered, I have them powered from the same supply that the 6600M runs from.

    I get a hum on 6 meter FM that I haven't been able to eliminate yet.


    Steve KD2OM

  • NB6Q
    NB6Q Member ✭✭

    Ferrite cores from Amazon next day did the trick, including 6m. Thanks again.

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