CWID stands for Continous Wave Identification. That is the Morse Code broadcast of the transmitter site's FCC Callsign. It is broadcast every 30 minutes usually on the last active channel in the trunk group for that tower. As an example, when the Partridge tower came up last month, I couldn't be sure which tower I was listenting to since there will eventually be at least two towers in Reno County. Once I caught the CWID broadcast of WQIB581, there was no doubt.....