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Problem w/6400 and PTT

On a previous post, I indicated that my 6400 was having issues transmitting with the included stock mic. Well after further review, it might be a PTT issue. I purchased a PTT switch and hooked it up to the RCA PTT jack on the back of the 6400. Currently I can transmit via my PC headset by clicking the MOX button and it works fine. However, pressing the PTT switch I connected, it is doing the exact same as the stock mic which was connected to the same PTT jack. No audio or modulation during transmittion. Am I missing a setting? Or is there a potential hardware problem? Any Ideas? Thanks!


  • VK7WH WinstonVK7WH Winston Member ✭✭
    edited June 2018
    Have you checked your TX settings are set to enable? Settings - Radio Setup - TX - RCA TX 1,2,3 I have a 6700 but your rig should be similar
  • Barry YoungBarry Young Member
    edited April 9
    Thank you for the reply. They are all enabled and set to value of zero.
  • Dudley  WA5QPZDudley WA5QPZ Member ✭✭
    edited March 21
    If you MOX button keys the radio, then the rear PTT , should also work, time to turn in HelpDesk ticket , http://helpdesk.flexradio.com .
  • Barry YoungBarry Young Member
    edited April 9
    Thank you I will do that..
  • edited June 2018
    I had a similar intermittent problem, and solved it with a very slight squeeze of the RCA barrel using a set of pliers. It apparently wasn’t making solid contact.
  • Barry YoungBarry Young Member
    edited April 9
    The PTT triggers, and the radio goes into transmit mode, just no modulation as it does via MOX. I opened a help desk issue. I don’t want to do anything that might void the warranty. Thanks!
  • Steve K9ZWSteve K9ZW Member ✭✭✭
    edited June 2018

     Check that the Microphone selection (Mic/Bal....) matches how you have it wired. 

    GL & 73

    Steve K9ZW

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