Hi Doug N9pkn, hope you are having a nice day
 I happen to have the service manuals for the 2900, and the 2950/2970
The mic connections are the same for all three and are as follows
1 Ground               4   
2 Audio                     3
3 Xmit             5    6     k
4 Recv                      1
5 Ch UP               2 
6 Ch DN                  
 It's not the greatest drawing, but this is looking at the front
of the radio. The "k" is the keyway.  Below is a schematic of the 
mic.  It is in recieve position and according to the manual the 
mic is a 400 ohm dynamic.  From experience, this has to be spec
unless you want to go in and reset everything for a different 
impeadence.
*
* 1----+--+---+---+----------------\
*      |  |   |   |                |
*      |  |   |   |               mic
*     UP DN   |   |                |
* 5---/   |   o ||o                o |
* 6------/      ||===================|==  PTT
*             o ||o                o |
* 3----------/    |                |
* 4--------------/                 |
* 2-------------------------------/
*
* If the astericks are in a line
* then the schematic is properly
* aligned.
 -=> Yours sincerely, Paul Williams KB5IVG <=-
... Definition of heaven: being alone with Dax playing connect-her-dots.
--- Terminate 4.00/Pro
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