On Feb 14, 2006, at 7:32 PM, Peter Todd wrote:

> I built a linear power supply using a 28A 6.3V transformer
> from digikey. 237-1255-ND. 4x LM396K 10A regulators in
> parallel through load-sharing resistors regulate the voltage.

What kind of filter caps have you got in there?  IIRC, you need
pretty big filter caps in big linear supplies, and that in turn
requires some sort of surge prevention to handle the turn-on
case where the cap acts as a dead short.

And what kind of heatsink for the bridge?  At 28A, it's going
to need to dissipate a goodly amount of power.  I've always
found it a bit mind boggling that one of the most heatsinked
elements of modern power supplies is the rectifier diode (more
so than the regulating element, frequently), but the math shows
it needs it...

BillW
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