[Elecraft] Yamaha CM500 Headset is a WINNER (and a BARGAIN)

[Jim Brown]

On Thu, 24 Dec 2009 04:01:18 -0800, K6LE wrote:

>I thought that too but what's puzzling is that the mic gets bias even 
>with the mono adaptor in line.

There's a wide variation in how computer sound cards are wired, so Yamaha 
provides adapters that make the mic work with as many of them as 
possible. There are several wiring tricks that can be played to provide 
the needed bias current. Since the CM500 works when plugged straight into 
my computers and the K3, I haven't bothered to study what those adapters 
do.

73,

Jim K9YC

>Rick
>K6LE

>On 12/23/2009, at 9:11 , Jim Brown wrote:

>> On Wed, 23 Dec 2009 16:56:44 -0800, K6LE wrote:
>> 
>>> It's a stereo plug 
>> 
>> No, it's not a "stereo" plug, it's a 3-circuit plug the CAN be used 
>> for stereo, or can be used for other things like an electret mic. It 
>> could also be used to carry shielded balanced audio wiring. 
>> 
>> With this mic, the tip is audio high, the sleeve is audio return and 
>> cable shield, and the ring is +Vdc to power the tiny impedance 
>> converter inside the mic. For more on this, see