A decoder output signal is provided, however, only if a second output signal from {HEAD ~ the comparator} is provided within {TAIL ~ a predetermined period} of time following the provision of the first output signal therefrom 
A decoder output signal is provided , however , only if a second output signal from { HEAD ~ the comparator } is provided within { TAIL ~ a predetermined period } of time following the provision of the first output signal therefrom
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH