Well, ok, supposing I gnd it to 'earth'. First of all, what do you mean grounding to earth? I mean if it's not grounding it to the mains ground.. would an example of 'earth' be grounding it to the psu case? And then grounding the circuit board to the case consequently? And this brings me to my next question: What's the point of mains ground then? What if I am working with my parallel port, which is grounded by the computer, which is grounding by the mains... and I connect my parport to a circuit powered by my psu, also grounded to my psu. They will have different grounds, won't they? Somewhere in this whole concept of GND I'm lost! Quoting Spehro Pefhany : > At 01:59 PM 1/27/2003 +1300, you wrote: > >Or using centre tap for fullwave rectifier :- > > > > > > metal frame grounded ____ > > Neutral to Earth | | > > +----------+ ---->|-----+---+-----7805|----+----o > > | | Diode | + | |____| | + > > C||C ### | | ### > > C||C --- | | --- > > C||C | | | | > > C||| | | | | > > C||+-----+----+----------+-------+--------+ > > C||| | | > > C||C === | > > C||C Earth | > > Hot C||C | > > +----------+ |----->|-------+ > > Diode > > > Sure, or full wave bridge to get +/- . ;-) > > Best regards, > > Spehro Pefhany --"it's the network..." "The Journey is the > reward" > speff@interlog.com Info for manufacturers: http://www.trexon.com > Embedded software/hardware/analog Info for designers: http://www.speff.com > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > ---------------------------------------- This mail sent through www.mywaterloo.ca -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu