The transformer may function at {HEAD ~ any desired frequency}, from very low frequencies through power frequencies and {TAIL ~ audio frequencies} to very high frequencies 
through
The transformer may function at { HEAD ~ any desired frequency } , from very low frequencies through power frequencies and { TAIL ~ audio frequencies } to very high frequencies
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH