[Elecraft] My KX3 desk microphone project

[Gary - NC3Z]

I wanted a desk mic to go along with my KX3 station. Wanted something 
more portable than the Heil boom and mic I use on my other radio. I have 
experimented with dynamic mics on the KX3 and didn't get the results I 
liked but did get very nice results with using 4 CUI electret condenser 
mic elements in parallel. I used the CUI CMA-4544PF-W from Digikey and 
used a small project circuit board to physically arrange them in a 2 x 2 
config. Then I trimmed up the board.

For the mic body I found a unused Shure 522 on ebay (some company had 
them for a conference table system and had a great price). The 522 has 
an adjustable neck height and a PTT (with lock). I gutted the body and 
fitted the new electret element assembly as well as used a 3' TRRS patch 
cable that I cut 1 end off for the mic cable, it also had 90 deg ends.

I am pleased with the physical results as well as very good audio 
reports I am receiving from the regulars that know my signal, still not 
to the level of my FTDX5000MP but getting better with each tweak and DSP 
update (using 1.32 which has made a noticeable improvement). I am using 
a healthy level of compression and mic gain that shows a solid 5 bars.

-- 

Gary Mitchelson
NC3Z Davidsonville, MD FM18
NC3Z/4 Pamlico County, NC FM15
www.mitchelson.org