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