Headphone adaptor

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  • Question
  • Updated 4 months ago
  • Answered
  • (Edited)
Trying to connect a Yamaha CM500 to my Flex 6300 . I have had a Heil Pro 7 connected to my Flex 6300 with no problem. Now with the CM500 Audio is working fine but I have no transmit output .
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Posted 4 months ago

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Frank Rode

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Hi Lee. I think you are using the headphone at pc's sound card. Audio source set to pc. With ptt I had also no output. With pushing the mox button I have output. Think that'should the issue you have
73 Frank
Photo of Mike


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Turn on the mic bias voltage in the settings menu.
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Chris Tate - N6WM, Elmer

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2 things if connecting directly to the flex, particularly if you are using the heil adapter in the front of the radio. 

DC bias ON
Stereo to mono connector on the mic connector

I use a CM500 frequently and this was how I was able to get it working.
Photo of Ray Andrews, K9DUR

Ray Andrews, K9DUR, Elmer

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N6WM has it right. The CM500 has a stereo plug with the mic element wired to both tip & ring. The Heil adapter has a mono jack. When you plug the headset mic into the adapter you short out the mic element. Stereo-to-mono adapters are dirt cheap on E-Bay. — 73, Ray, K9DUR