From Kevin, KB9RLW
My home brew USB interface for all ham radio digital modes. Unique in that it uses an Arduino micro controller for the VOX function. This makes it very flexible and tweakable. One thing I didn’t mention in the video. You want to set the playback volume of the interfaces sound card to maximum on your computer. Then use the drive level knob to adjust the audio drive to your rig. This gives the vox plenty of signal to work with.
I intended to include the Arduino source code here, however youtube wouldn’t allow some of the characters in the code!!! Very disappointed, but I understand why.
I put that info on my blogspot blog. You can get the schematic and source code here.