The associated circuitry within the transponder does the actual testing and includes an oscillator, {TAIL ~ a transmit frequency circuit}, a self test interrogation circuit, and {HEAD ~ forward power detectors} 
The associated circuitry within the transponder does the actual testing and includes an oscillator , { TAIL ~ a transmit frequency circuit } , a self test interrogation circuit , and { HEAD ~ forward power detectors }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD