At 14:08 -0400 7/14/10, Dan wrote:
>Best to try things in advance...

Yep.  And it would be pretty hard to find a power converter that would damage 
any of today's computer power converters. If it doesn't work don't leave it 
hooked up too long and pay attention to hot spots that shouldn't be.

Cheap converters for automotive cigarette lighters almost always convert to a 
square wave form of AC power. The voltage changes quickly from +115 volts to 
-115 volts about 60 times per second. That's quite different from utility power 
that changes as a smooth sine wave that averages out (in delivered power) to 
115 volts.

More expensive converters as found in mobile homes do a better job matching the 
voltage waveform.

The internal power converters in computers these days make an effort to avoid 
drawing current that is not sinusoidal. It's called harmonic suppression and is 
required in many countries but not in the US of A.  When the harmonic 
suppression circuitry encounters a square wave voltage, which has terrible 
harmonics to start with, it can get confused and not work properly because it 
tries to accept current only while the voltage is changing. For a square wave 
the voltage is only changing for very short periods of time.

<ftp://ftp.macnauchtan.com/Theory/Harmony_101.pdf>  Is a piece I wrote a long 
time ago about it. You'll need to know a little math and electricity but it's 
pretty short.

-- 

--> Evolution made it possible for mankind to invent religion. <--

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