Headset mic connections

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  • Updated 3 years ago
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I have a Steelseries V3 PC-Gamer headset which has a single 4-pin phone plug at the end (REar, LEar, Mic, Gnd).  Can I build an adapter to plug this into the 8-pin Foster on the 6500?  The diagram for the Foster shows Mic+ and Mic-.  Can I ground Mic-?  or do I need some sort of isolating capacitor from Mic- to ground?

Thanks for your help.

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Posted 3 years ago

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Photo of WA2SQQ


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Official Response
I actually made an adapter box with both 2.5mm and 3.5mm female jacks. These accommodate just about any mobile headset used on cordless and mobile devices. For Standard 2.5mm Cellphone Headsets, also called Universal Headsets.
tip = microphone
ring = speaker
sleeve = ground

Note the Microphone is a electret condenser microphone so it will need bias voltage. To simplify matters i added the cap externally. wiring is simple I get the voltage from the mic plug on the Flex 6500. Feed the voltage to a 4,7K resistor. The other side of the resistor is connected to the + of  a capacitor, I used 47 uf . The junction of the resistor and capacitor gets connected to the Mic+ of the headset. Headset Mic ground gets connected to mic ground on Flex mic connector. An external PTT can be wired to the mic plug or the PTT connection on the rear of he 6500. I've tried several headsets - you'd be amazed how good some sound, one of my best purchased at my local "dollar store". EQ to your desired specification!