{HEAD ~ A trigger coil} generates {TAIL ~ a trigger signal} for application to the trigger of the switches 
generates
{ HEAD ~ A trigger coil } generates { TAIL ~ a trigger signal } for application to the trigger of the switches
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH