In {HEAD ~ some embodiments} of the invention, a locator transceiver can include a receiver and {TAIL ~ transmitter} 
In { HEAD ~ some embodiments } of the invention , a locator transceiver can include a receiver and { TAIL ~ transmitter }
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL