Here's an oddball, too:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260
42V, 50hz. Apparently, there were mains lines that delivered those
values to special plugs in Russian schools. How would one go about
powering such a device in the US?
What is the device? In particular, is it going to care about the mains
frequency. If it caould run at 42V 60Hz, you could use a simple step-down
transofrmer to run it, I would recomend a double-wound (isolating)
transformer, since an autotransformer, could end up putting the device
110V above ground, and I;d not trust the insulation to stand that.
If it really does require 50Hzm then you basically either have to use a
motor-generator set or rectify the US mains to get DC and re-chop it at
50Hz. You mightm for example, be abke to use one of the better
(sine-wave output) Europena-market inverters to get 'mains' from a car
battery (that would give you 230V, 50Hz) and a step-down transoformer.
-tony