I have not tested that solution. I just copied it from the ICOM schematics. I guess most components from the junkbox will work it’s not critical
Our solution is based on a comparator, I designed it before I saw the ICOM schematics, but it’s more difficult to build by yourself as it is SMD components
I have ordered some TO-92 FETs to test with (we only have SMD in stock), I will update the schematics when I have tested with them.
Rgds
Mike