Well after a few years in my short professional career, I finally had to squawk 7600 today. I was on the ILS 29R into SCK, just at the FAF inbound when the GPS and Coms went dead. I checked everything and noticed that the alternator gauge showed a discharge and was almost gone. Had to turn off everything except the stobes, which allowed the transponder to work (a bit). So I squawked 7600 and got the light gun signals to land and taxi.
Aircraft? I'm glad you asked!! It's the Alarus!
Neil