With a set of normal work of the product, the first demonstration of normal work, and then close one of the microphone, the other to find a microphone, with the receiver frequency (no search frequency, only frequency, frequency unchanged), after the frequency The new microphone can be put into work. At this point if the closure of the new microphone, open the original that microphone, the receiver will not receive, that is, that the original loss of legal identity. Be careful not to open the old and new two microphones at the same time, or two of the same frequency, the equivalent of a serious interference with the same frequency, both can not receive.