a) Any of the switcher wallwart devices [aka "100-240V"] will
be fine on 240. Your sole concern is plug conversion. If you
can confirm that, i.e. be 100% sure no 120V only device will be
along; then I might be talked into a hack solution, a 240 plug
on a metal outlet strip w/120 receptacles.

But I bet some luser plugs his 120-only something in when
your back is turned, and it's history....

b) Many of the "travelers voltage converters" are garbage, and
will destroy the device plugged into them. Some are crude diode
choppers, others series resistors, etc. Incandescent lamps and
hair driers are about the only safe loads.

c) Any real transformer solution will be HEAVY for given watts
of load.

Hope this helps.
--
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