Wired: Make sure the battery is not in the Microphone. And plug the cord to the microphone and your audio amplifier Switch microphone to MIC position and start to sing Wireless: Install batteries into both microphone and receiver. Switch on them the connection will be built easily. With LED indicator Switch microphone to ON position and start to sing Switch microphone to MIC position when you need a short break. It won't collect other voices to the microphone If it does not work normal. Use a screw to press the RESET hole on the receiver If you don't use it for long time. Please take batteries(not included)out to protect the microphone's components Frequency range: FM Frequency response: 100Hz1000hz S/N ration: ≥60dB Directivity: unidirectional Operating voltage: DC 1.5V Service areas: 8~20 Meters Reception sensitivity: 30dB/uV Wired sensitivity: 50dB±3dB(0dB=1V/Pa) Impedance: 600Ω Note: A receiver can only be used with one microphone not with multiple microphones. You can not use 2 or more Microphones with the same color indicator at the same time! If two wireless microphones are used at the same time you must use them with one red and one green indicator and use them with both receivers turned on.