Recently I bought a 1Mhz ultrasonic transmitter receiver pair from Alibaba site. The proper datasheet was not available for the same. Since my need for 1 Mhz ultrasonic sensor was urgent, though without proper datasheet I ordered for the same. When it came it had three outlet wires coming out,one in red, one in white and the other one was without any coating,(looks like Aluminium ). Have any one used this sensor module before? If yes can somebody help me with the proper connections that have to be made to each? When I did trial and error,with the uncoated one as ground an red as the input the module is transmitting and at the receiver part also the uncoated one was gnd and the red end was receiving,I was able to receive the signal .But the each white wire of both modules were left open.So is this the proper way of doing it?When I assumed the module as self transmitting and receiving,I checked whether white is receiving any signal,but it didn't. Can somebody help me??