They don't mention frequency. Normal power is 60Hz, AM radio is 500-1600KHz, FM is 80-120MHz, microwaves are GHz. I heard some military aircraft use 400Hz for powering their electric motors to keep them small and light.

__________________
'Sir........, I don't like these numbers.'
'Then hire somebody that can change them!'
("`-/")_.-'"``-.,,
\. . `; -._( );, `)
(v_,)' _ )`-. \ ``'`
_.- _..-/ /((.'
((,.-' ((,/