Related reading:

The Stator Papers I: APrimer on GS charging systems (youshould've read that first, it explains the theory referred to in this Q&A)

TheStator Papers II: FAQs

The Stator Papers III - The Solution, detailsabout the availability of the Electrex unit.

The Stator Papers IV - The Fault Finding Chart,a comprehensive, step-by-step fault findingprocedure.

The Stator Papers V - Cause #1 for failingcharging systems: bad conductivity! 

The Stator Papers VI - How to rewind your ownstator