Alternator..?

Tried to start my car yesterday, when I got in I noticed my dash clock was off along with all of my electronics =( the car of course wouldn't start, so I assumed that I must have left something on the night before and drained the battery. Later I tried to jump start the car so I could let it idle and build up a charge, however as soon as we disconnected the cables and I let go of the gas, the engine stalled (we let it high idle for about 20 minutes). I then suspected that something was wrong with the battery, it was only 3 months old so I took it back to the shop and they gave me a new one, but he also told me that it was just dead and could be charged (they ran the test on it there). He sugested maybe something was wrong with my alternator. I had been working on the car about 3 days before, and I changed all of the belts so I figured maybe that had something to do with it. When we got back I decided not to hook the battery up yet in fear of just draining it. All of the belts look fine, nice and tight but not too tight, as far as I can tell every thing was put back correctly..

Any way I'm going down to my friends house later, he has a volt meter so I'm going to put it on the new battery while the car is running and see if it's being charged or not. In the likely event that it is NOT being charged I'm going to get under the car and see if anything is obviously wrong or disconnected from the alternator, and I'll check all of my fuses because I think there is one for the alternator..

Any thing else I should be looking for? I really don't feel like replacing the alternator if thats the problem, and I've never had any problems with it since I've bought the car.. What ever happened it must have happend when I was working on the car last week =\

(1990 Sohc)

Also, we drove the car over 200 miles since the we changed all of the belts, so it was running fine for a while.

i think it'd be the altenator, it may of just died randomly

a friend of mine was driving a newer hyundai and the car stalled for no reason, and would not start again. so we boosted it and it started fine, we let it run for a bit and when we took off the booster cables, the car could not hold the charge and just shut off, so in that case it was the altenator for sure

so ya, altenator would most likely be the problem
check all the wiring to the alt and see if it's all good, maybe one just became loose

Okay, just got back, unpluged the battery gets 12.6 volts, when I start the car up it goes to 12.2-12.3volts. It's my understanding that it should be reading closer to 13-14 volts if the alternator is working and charging the battery, (although the battery is fully charged right now, not sure if the alternator stops charging it when it is full.)

As far as I can tell everything is plugged into the alternator, the belt isn't slipping or anything, the fuse is fine, and the battery light on the dash is NOT lighting up, it didn't before either which I thought was odd. Isn't the light suposed to come on if the alternator is disconnected? The bulb works though, it comes on when I test the lights.

Any one know about that voltage stuff? should the battery be putting out more volts like that when running? If not then my problem has mysteriously fixed it's self.

wtf >=(