AW: (not so) Simple Power Supply Stuff

[MACHINE MEDIA]

> And add another 20% to make sure that your gear is still working
> when the mains voltage drops!
> A few weeks ago, our power supply company changed, and we had
> some severe undervoltage in our town. Hey, that's funny if you hear
> your studio equipment fail one by one!

This isn't that rare of a problem.  I have power line conditioners on all 
my studio gear which is set up near an industrial area -- if I get really 
bored I can hook an AC voltmeter to the mains and watch the needle swing 
up and down when the factories change shifts!!

Several designers have also addressed this problem by building their gear 
with switching power supplies.  One device that had terrible 
problems with live sound was the Lexicon PCM-70 -- the whole thing would 
go nuts with the slightest dip at the mains.  They have now corrected 
this problem by putting a switching supply in the PCM-80.

Here in the U.S. line voltages vary greatly from place to place.  I've 
set up gear in places with mains as anemic as 105VAC, or as hot as 
125VAC.  One should never assume that the voltage is 115 (or 117) -- 
especially when designing a power supply.

PEACE OUT :)
MARK