Hi Elecrafters and N3AO I have used a stereo headset with the electret mike on my KX3 for more than five years now Brand name is /Andrea, / model NC-65 ~ comes with an 8 foot cable with the appropriate 3/16" stereo plugs SETTINGS: on the KX3 I have the MIC gain ~ 43 and the VOX DLY ~ 0.20 Regards, Jan K1ND