Mic

I tried the mic that worked last time, the Cobra power mic, but it didn't work at all.  For some reason it didn't key the radio. 
Then I tried the second mic, a Powered Uniden Desk Mic.  It doesn't want to work either.  I have to run the mic gain up to max to get any little bit of output...

So next I'm going to wire up this Sure 444 mic.  But I have to figure out the pinout first...






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Mic wiring #3

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I wired up a bunch of microphones.  The Cobra power mic that I used last time developed a broken wire, so I had to repair that one before I could test it.  The Uniden amplified mic didn't give enough gain. The Cobra Power mic did OK, but not full power. The Yaesu MD-1 gave some output power, but the mic gain on the radio had to be at 10. Finally I wired up the Shure 444T.  Even though it is a Low Z microphone, it worked the best. I could get power output out of the radio on SSB with a reasonable mic gain setting.  Between 2 and 4. Looks like that is the best mic so far. Through testing, It looks like I'm getting between 75 and 95 watts out on 20 meter SSB.  There may be a little drift over several minutes, but it doesn't seem bad.
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