imsai 2

<Anyway, why does it have to be one transformer? Why not a 12-0-12 for the <16V lines and a 6V one for the 8V line (those should produce DC voltages <within the range of any normal S100 board regulator). Such transformers <are trivial to obtain. Then you'd end up with the piece of crap altair supply... <There is a myth doing the rounds that PSUs -- even simple linear PSUs -- <are impossible to design. No idea where it came from... Because any error means all your silicon is junk. Also if you make a small error the core you using could get quite hot. Or maybe the ripple there are the high current ground loops that cause instability at something approaching max load or minimum load. The worst is when you forget the chopper side has 300V on it, S*!^^ d@**. The number of errors that can be made are far higher. Then again having designed a few, once you've done it you learn... mostly everything they taught you was far from enough. that and fixing all those that were really not so well designed. Allison