The fail safe circuit also includes circuitry for preventing inadvertent communication of the signal from the input terminal through the series switching network to the output terminal when one of {HEAD ~ the switching circuits} is in {TAIL ~ a short circuited state} or condition 
is in
The fail safe circuit also includes circuitry for preventing inadvertent communication of the signal from the input terminal through the series switching network to the output terminal when one of { HEAD ~ the switching circuits } is in { TAIL ~ a short circuited state } or condition
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH