Electrical problems 93 transport.3.8 ltr

Hello, I was out canvassing for the Kidney Foundation when i noticed a burned wire smell inside the van(only thing running at the time was heater)-I then heard the heater fan was not running right(making a squeeking clicking noise) so I shut it down right away (it does have bad high speed relay just havn't had a chance to change yet) anyways-the smell went away and everything was good-I just stopped using the front heater fan, then I started to get an interferance noise out of the radio (high pitch whining/buzzing noise that matches revvs on the engine) and the ABS light stayed on-Then yesterday as I was driving the interferance noise became louder and started to make a buzz noise on and off -then the van started to buck a bit but I drove home and put it in park-then was trying to rev it up but it was acting sluggish and the tach indicator needle was going the wrong way and pinning down at the bottom-I shut it off right away and left it-I came back after awhile (pulled the heater fuse) and it started right up and ran ok(but the heater could still be turned on with fuse out) I then turned it off and it wouldnt start again as the battery was not strong enough-any Ideas? I can put a multi meter inbetween the batt post and connector and pull fuses to see what circuit may be bad-but any other suggestions? This van was working so very good and I hate to scrap it over this-any way to check the charging system to see if it is working right now? Thanks guys any assistance would be awesome!

First suspicion is alternator failure, a common problem. If you can start it again, check voltage : it should read around 14.2 or slightly more when cold. Most symptoms you decribe are relevant of low system voltage. I think you have at least one open diode in the alternator. IN any case, an easy check before looking for more complicated...there is ample time left to come to that....