With the engine at idle the AC voltage read .1 volts. After switching the headlights on and with the fan on defrost, the DC voltage on the battery only read 11.8 volts. At 2000rpm, voltmeter only read 12.1 volts. I was not able to test/tighten the alternator belt tonight, but will have that done by tommorrow. The thing is that I bought the battery only 10 days ago, had the alternator rebuilt 3 days ago, and checked the wiring/made my own wiring harness but got the same results. Alternator shop suggested that something was wrong with the battery, but now I just don't know what is going on.