CP from yamtripples:
"Through my learning about voltage regulators, I discovered that there are two circuit types of regulators. You have a type "A-circuit" and type "B-circuit" when it comes to voltage regulators. The difference is that in the A circuit: the voltage regulator field wire (F) provides 'ground' to the field coil while in the
B circuit: the voltage regualtor field wire provides 'power' to the field coil. The original voltage regulator in the xs750 appears to be a type "A-circuit", the Bosch type R588 BWD external voltage regulator I tried first was a "B-circuit" regulator. "
does anyone know or have any ideas on how to verify which type is on the 400?