Mystery solved with the flickering light on my PlanePower alternator.
That darned light has been flickering faintly for at least 100hrs, even though it has always produced good power. The alternator has been bench tested but not disassembled
The alternator finally quit at 261 hrs, so it went to our local shop and $120+tax later it is back in service.
The fix was a new stator. Turns out the stator is not keyed into position, but merely clamped by the case screws. In this case there was slight rotational movement as evident from the chafing marks, and over time this broke the connections to the stator. Needless to say the new stator is fixed, I believe with a Loctite product.
No more flicker.
RV7 tip up
IO360 Whirlwind 200RV
Building RV8 with buddy