1995 HD ultra classic-need help

My 95 ultra has had a drain on the battery for a while.  No mechanic can seem to solve my problem.
Since I last got out from a dealer my radio is not working and my brake light does not work.  But the brake lights on the luggage rack work.  When everything worked, these were the symptoms:
Touching the brake levers reduced the alt meter
Turning on the aux lights reduced the alt meter
With the radio off a loud humming noise came thru the rear speakers
I know there is a voltage drain some where but don't know where to start.  Any suggestions?? Thanks  

Check your stator and a mechanic may tell you that isn't it but it sounds like the problem.... H