The spectrum is measured over a time period of {TAIL ~ 1 to 1000 seconds}, at {HEAD ~ intervals} of 5 to 10 milliseconds or less 
The spectrum is measured over a time period of { TAIL ~ 1 to 1000 seconds } , at { HEAD ~ intervals } of 5 to 10 milliseconds or less
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH