The on off state of switch 56 is controlled by {HEAD ~ switching signals} 57 coupled to a control terminal 58 of {TAIL ~ switch} 56 
The on off state of switch 56 is controlled by { HEAD ~ switching signals } 57 coupled to a control terminal 58 of { TAIL ~ switch } 56
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH