Edward Bartolo:
...
> For instance, a mains transformer based power supply, normally has a
> far longer life than a switched mode power supply, although the latter
...

There are several drawback useing the old transformer + rectifier
design. Of main consern is the current spikes seen on the power grid
when the diodes starts to conduct. Your power supplier don't like them
and that is why we have PFC to make the unit behave more like a
resistor to the power grid.

Regards,
/Karl Hammar

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