Re: uBITX Mic Wireup

Dave Bottom <ars.kd6az@...>
 

Connecting the Mic- to ground to generate PTT is common for many handheld radios. It saves a wire in the cable.  

You’ll need to rewire the Mic and PTT SW to work with the uBITX which is exactly the way you would wire it work with most QRP radios including Elecraft’s KX2/KX3 radios.

Dave WI6R


On Mar 8, 2018, at 7:54 PM, Shaun <slong682000@...> wrote:

 Does anybody have a diagram or description of the mic wire up for the uBITX? I am looking for the mic itself, not the mic jack on the transceiver. Most of the mic's I have dealt with have the MIC+ going to one side of the electret and MIC- or ground routing through the PTT switch when it is closed, completing the circuit. Looking at the uBITX schematic and a mic wireup for an older version of BITX from several years ago on the forum, what I think I am seeing is that the sleeve is providing a constant ground to both the MIC- side of the electret and one side of the PTT switch. The tip connects a constant output to the other side of the PTT switch and the ring is providing a constant output to the MIC+ side of the electret. It almost looks like the electret is an "always on" state but the output is not utilized until the separate PTT circuit is completed. Any help would be appreciated.

Shaun
KEØNLN

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