IC-746 FAQ
Another good QST article on microphone preamps is:
"Adapting the Astatic D-104 Microphone for use with Modern Transceivers"
QST, Aug, 1999, p.34
a copy of which can be found at:
http://members.aol.com/ampmicro/
Another interesting design can be found at:
http://www.muzique.com/ssm2166.gif
3.3.6
What are the pin-outs on the microphone connector?
As listed on page 67 of the Instruction Manual:
1 - mic input
2 - +8V DC Output at up to 10ma
3 - freq up/down
4 - Main readout squelch switch
5 - PTT
6 - GND (PTT)
7 - GND (MIC)
8 - AF Out (varies with [AF]) (center pin)
Page 39 of 113
2003-02-08