Sorry for the late response, its been hectic the past few days. With your engine off you should have a battery voltage of around 12.4 to 12.6 (this is according to Haynes) when the engine is running, the voltage should be greater, but not more than 15 volts. (again so says Haynes)
I would check all of the alternator wiring, making sure its in good condition, also in what condition are the belts that attach to the alternator? I hope this helps.
She may not look like much, but she's got it where it counts, kid
-Han Solo to Luke Skywalker