72 Swinger not charging battery

scudzuki said
That's what it's supposed to measure, less than 12V. That's supplied by the VR. With the key off both fields terminals (with their respective VR wires connected) measure in the mv range

The blue wire is supposed to be battery voltage to the VR and to the alternator. So if you measure the blue wire anywhere along it's path it should be battery voltage, at the VR or at the field terminal on the alternator.

The green wire will have varing voltages on it as the VR determines how much voltage the alt needs to supply.

Note the pin locations are just for example on the VR.
(I goofed on the line from the ballast to the coil. It will be less than battery voltage)

In a grounded field alternator one field terminal is grounded and the other coming from the VR varies from about 6 to 10 v.