When working on the remote operation of the FT-991a, I wanted a solution that included my favorite mic/headset into the mix. Heil makes great stuff, but the adapters can be pricey. So, I started with trolling Amazon for a solution.
The Heil Pro7 headset that I have has two 1/8-inch plugs that represent the mono microphone (2-pole, TS), and stereo speakers (3-pole, TRS):
Amazon has a plethora of choices for USB microphone adapters and since the my Pro7s use a dynamic mic, I went with an XLR-type adapter to start. (Since I am a musician — I figure I can use the leftover connector and cable elsewhere.) To adapt the microphone I added an 1/8-inch inline TS jack to the module with a short piece of microphone cable. In the photo below the organization of signals (top to bottom) are; shield, common, mic.
The shield and common are connected at the body of the 1/8-inch jack (aka ring). The mic (red in the photo above) is tied to the tip.
When using the headset, I plug the headphones into the laptop headset jack, and the mic into this USB adapter. The audio levels through the USB adapter are a bit lower than one might expect. This is not an issue, since you can either adjust the FT-991 mic gain and compression, or just leave it up to VoiceMeeter to bring the levels up. VoiceMeeter brings the audio input levels to what the Pro7’s would be if plugged into the transceiver directly.
For more information on this setup, refer to — FT-991a Remote Rig Setup.
73!