For those who do not understand the technicalities, I would suggest that the CM-500 cannot be plugged directly into the KX3 jack. The KX3 PTT is on the ring connection, and the stock CM-500 connects the Tip and ring together for the AF connection.
It MAY work, but it is not a certainty, the KX3 function of the ring contact is three-fold - PTT, UP and DWN. the audio level on the ring may or may not induce one of those functions depending on the voltage and current. It would be better to create a homebrew adapter that would accept the CM-500 AF on the tip and ring, and connect that only to the tip of the KX3 jack, and at the same time add a small box with a pushbutton for PTT and also pushbuttons (with the appropriate resistors) for UP and DWN). In other words, the stock CM-500 *may* work, but it may not depending on the levels presented at the ring connection. This situation may also be present in microphone designed primarily for computer use - they may be OK, but if they create funny PTT or UP or DWN conditions, blame it on the connection between tip and ring on the microphone jack. 73, Don W3FPR On 3/8/2012 3:46 PM, Joe Subich, W4TV wrote: >> As for the CM-500, I'd like to know if it is the tip, or ring, on the >> 1/8 inch plug that is the actual mic audio lead. I will have to try >> one, or the other, to see. > The answer is quite simple ... the tip and ring of the CM-500 mic plug > are connected together. > > The supplied battery box has no connection to the ring of the mic > (3.5mm jack). Tip of the jack is connected to tip and ring of the > 3.5mm plug via a 1 uF capacitor. The positive side of the battery > (+3.0V) is connected to the tip of the 3.5mm jack with a 2.2K Ohm > resistor. The negative side of the battery is connected to sleeve > (common/ground) of both plug and jack (input/output). > > 73, > > ... Joe, W4TV > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
