{TAIL ~ A time switch} comprises terminals spaced around a slip ring connected to {HEAD ~ a voltage source}  
{ TAIL ~ A time switch } comprises terminals spaced around a slip ring connected to { HEAD ~ a voltage source }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH