Koss SB40 and AD-1-Y Connector

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  • Question
  • Updated 3 years ago
  • Answered
I am trying to use my Koss SB40 headset with the AD-1-Y adapter cable on my Flex 6300 and it is not working. I tried turning on Bias in SmartSDR and I get no audio transmitting at all.

Did I get the wrong adapter?
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Posted 3 years ago

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Photo of Ray Andrews, K9DUR

Ray Andrews, K9DUR, Elmer

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Official Response
This may be the same problem as with using the Heil adapter with a Yamaha CM-500. The Yamaha has a stereo mic plug, with the element wired to both the tip & ring. The Heil adapter has a mono mic jack. Therefore, when you plug the mic into the adapter, you short out the mic element. I found a stereo to mono adapter on EBay for about $2. Plug it between the mic & the Heil adapter, & all is well.

73, Ray, K9DUR
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Danny K5CG

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Official Response
I homebrewed a jumper for both.
SB40 pin 7 to sleeve, pin 8 to tip. Bias off.
SB45 pin 7 to sleeve, pin 8 to tip and ring (shorted at the jack). Bias on.
If I recall I didn't need the +20db gain on either headset.