unknown machine - test-drb@ccmp.vtda.org

25 Dec 2011

or something unusual for mains power; ISTR something somewhere that
...
 >  had a mains power frequency in the kHz, or at
least hundreds of
>  Hz....) 
...
   >  IIIRC,
power line losses increas with frequency, so this would be
 >  unusual to say the least.  I think it was something that, like a boat or
airplane, is not part of
 the large-scale power grid but which does have enough of a power
 distribution system for it to be fair to call it "mains".

 But that memory is pretty fuzzy; I could be just plain misremembering.
 Planes use 400 Hz. US Navy ships seem to use 450 and 120V 400 Hz for 
electronics and weapons systems and servicing aircraft. Presumably any 
other country's aircraft carriers also provide 400Hz power for the aircraft.

/Jonas