MODS 6:

ALTERNATOR WARNING LIGHT

Problem: During flight, if the alternator failed, what would immediately warn you of the problem? The voltmeter is by your feet, out of the normal scan area. The difference between a charging unit (@14V+-) and the battery 12V is @a needle’s width! Hard to notice while fully occupied piloting the helicopter.

Solution: Indicator (Idiot) Light

The red LED with leads and resistor was purchased from Auto
Zone. The mount was purchased from Radio Shack.

The connection on the alternator is the "D" terminal. The downside of this installation is that it only indicates total failure of the alternator.

Another, better, alternative is this warning light from England. Available on E Bay for @$21.