Using PC Headsets & Professional Mics on Amateur Radio Rigs
Why would you want to do this?
Speaker mics are only so effective, especially when you're wanting to get into contesting. You can come across much clearer and stick out in pileups. With the addition of a PTT foot switch, this leaves your hands completely free to log QSOs, and ergonomically speaking helps keep them at rest.
Caveats
If you like to use a speaker mic still for casual use, you're going to have to find an easy way to swap out cabling. Also all mics are not created equal. You'll need to find out which mics are best suited for amateur use. A Heil PR40 for example, is a wonderful vocal mic, but horrible for radio becuase the mic picks up bass frequencies really well. With the narrow bandwidth used for SSB, you're really not using the mic to its fullest capability. On AM however, that mic would be better suited.
If I'm using a mic, why not also use a mixer?
You can, and actually, it's probably better that way, since you can use the EQ knobs to shape your voice to stick out really well by eliminating not used frequencies and accentuating ones you will be using (around 2.3k hz for example)
Electret vs Dynamic
The main issue you’ll come across is whether or not your radio is set for dynamic microphones or electret microphones.
The short answer is: unless your radio is an Icom, it will be wired for dynamic.
What uses an electret microphone? Most PC headset mics.
Wiring up the radios
If you are not using a mixer, and going into the radio directly at mic level via the mic connector, keep this wiring in mind:
https://jaazz.me/2014/03/11/how-to-wire-an-unbalanced-microphone-to-a-balanced-xlr-input/
Most radios have just a mic input line and ground, so you'll need to take the balanced mic circuit and convert it to unbalanced.
With electret microphones, follow this diagram if hooking up to a Kenwood or Yaesu radio (http://www.kingsqueak.org/pages/2009-06-22-pc-headset-adapter-for-ham-radio.html). The variable will be the resistor needed between Mic (before the capacitor) and Ground/Mic Ground. I noticed a several hundred ohm difference between two gaming headsets. Use a variable pot, or use a breakout board and test resistor values. Start low, in the hundreds first instead of 4.7k in the link. The lower the resistance, the quieter the mic will be. Keep your mic gain in the middle, and tune your resistance to match the volume level as best as you can. Use the ALC meter for your levels.
HyperX Cloud II - ~790ohms Cheapie Razer Kraken - ~500ohms
Kenwood
Yaesu
Icom
Sources
https://www.qsl.net/g4wpw/date.html http://www.hamuniverse.com/w6jmfpcheadsetadpt.html https://www.w2eny.com/adapter/ https://w2eny.com/adapterbatterybox/ https://forums.qrz.com/index.php?threads/pc-headset-heil-adapter.325964/ https://forums.qrz.com/index.php?threads/no-headset-mic-audio.597467/ https://www.reddit.com/r/amateurradio/comments/7keoun/headset_for_kenwood_vm71a/ https://www.n1fd.org/2016/04/27/rig-audio-interfacing/ https://www.cablechick.com.au/blog/understanding-trrs-and-audio-jacks/ https://www.cablechick.com.au/cables/avencore-4-pole-trrs-to-35mm-stereo-mic-splitter-cable-female-to-2x-male.html