Hi Doug N9pkn, hope you are having a nice day
DN>     Thanks for the info.  I have a mic that can operate at either 10k 
 No problem.
DN>Ohms or 600 Ohms.  If I use the 600 Ohms setting, will that be close
DN>enough to the input imedence of the radio to produce reasonable audio
DN>or will I need to build an impedence match for the mic?
 That should be close enough.  You'll have to adjust the mic gain 
accordingly, but it should work.  Interestingly enough, the 2900
has the same input circuit (except for the tie to the audio out amp)
The mic I used with the 2900 (bought used 2900 with a different mic)
was transformer coupled and worked just fine, but with the 2950 I could
yell into the mic with a bullhorn, and be asked why I was whispering. 
Needless to say, I switched mic elements *real* quick.
 -=> Yours sincerely, Paul Williams KB5IVG <=-
... Discoveries are often made by not following instructions
--- Terminate 4.00/Pro
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