Phase detector for {HEAD ~ a vortex flowmeter} using {TAIL ~ ultrasonic transducers} connected to separate transformers for phase detection 
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Phase detector for { HEAD ~ a vortex flowmeter } using { TAIL ~ ultrasonic transducers } connected to separate transformers for phase detection
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH