Marcel Duchamp wrote: > Crist=F3v=E3o Dalla Costa wrote: > = >> On 5/17/07, Dwayne Reid wrote: >> = >>> Yikes! >>> >>> I'm glad you haven't been hurt by this. >>> >>> Yeas - its obvious. >>> >>> Here's the deal. Your computer and probably much >>> of your mains-powered test equipment is grounded >>> to the AC mains ground. When you connect the >>> negative rail of your HV supply to ground, you >>> are essentially shorting out either D7 or D8. >>> = >> Hello >> >> With nothing but the diodes and capacitors in the schematic I still >> have trouble (can't connect the sides or smoke appears). No computer >> connected, nothing else. >> >> Am I still missing something? >> = > > Possibly. Dwayne's explanation is right; but your circuit should work on = > it's own with nothing attached. So maybe it did work right until you = > attached something and then fried a diode. > > If, as Dwayne mentioned, D7 or D8 got shorted out, then D5 or D6 (or = > both) might have easily been overloaded and either opened or shorted. > > Although you can replace them if they are bad, you won't be able to = > connect up your computer to it safely. > > = Somehow related to the question of the OP: In a PC are digital and frame grounds connected together and in turn = connected to AC main ground? Gaston -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist