Low voltage = no charging

I have a crazy problem, and in need of some serious help. My 71 Duster with a 340 isn't charging. The battery is at 12v even at the alt. Once I crank the motor up the alt is putting out like 11.3v. I have checked all the wiring and everything seems to check out. The only problem I see is my electronic ignition box. With the blue/yellow striped wire unplugged from the ballast it is reading 1.6v for some reason. Now while it is unplugged I 11.9-12.0v on the ballast resistor. Once I plug the blue/yellow stripped wire to the 12v feed on the ballast it drops to 9.8-10.1v. The alt will never charge when the field wires are at those low volts. Has anybody else ever had this problem? It has absolutly got me stumped.