Re: electrolytic mystery

From: Walter Harley (walterh_at_cafewalterNOSPAM.com)
Date: 08/24/04 

Date: 24 Aug 2004 06:31:55 GMT

"Ross Herbert" <rherber1SPAMEX@bigpond.net.au> wrote in message
news:j5hli0l2cmq1av5ctsg727qa1nu7g8if7n@4ax.com...
> The SC mic amp is designed to run from either a plugpack, batteries OR
> phantom power, so it would be similar to your situation. I'm still
> willing to bet that if you plugged the SC mic amp output into your
> mixer input (or any other commercial unit supplying phantom power) the
> caps wouldn't blow up even if it was powered by the battery or
> plugpack. The 48V from the mixer input phantom supply would not cause
> any problems in this situation. Thus the SC mic amp would conform to
> the requirements for all other units which were also capable of
> similar connection methods.

You would win that bet, if I were foolish enough to take it. But would you
make the same bet if you removed the 1k resistors that allow the unit to be
phantom powered?

The point here is that, regardless of how the unit is being powered at any
particular time, the 1k resistors pull down the voltage. But in the case of
a unit that is not *capable* of being phantom powered, those resistors do
not exist, and the output capacitors see the full 48V, despite being rated
for less.

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