Yes, I believe fuse-first, then diode is what MVS Sarma's solution does, once the reverse polarity of the jack is accounted for.? The wiring diagram on this group's assembly page, however, seems to have no particular dependency.? I guess the fuse would probably go first, assuming it reacts faster than the diode, but the ?BITX would be exposed to the reverse voltage before the fuse blew, and the diode would blow too.
But my understanding of this sort of stuff isn't terribly extensive, so someone probably needs to verify my assessment.? Any suggestions?