WR601 Wireless Amplifier MicrophoneLavalier Microphone For Meeting & Etiquette, Random Light Colors Delivery Performance parameters: 1. Sensitivity: -52dB 2. Distortion: 0.5% 3. Effective distance: 15m 4. Directivity: single direction 5. Transmittingreceiving frequency: 114MHz-116MHz 6. Frequency range: 111-116MHz 7. Frequency response: 100-13000Hz 8. Modulation method: FM 9. Effective working range: 8-20m 10. Power consumption: 70mA 11. Signal to noise ratio: 60dB 12. Size: about 14x12x3.5 cm 13. Weight: about 0.17 kg Instructions: 1. Open the bottom cover of the transmitter, insert a 9v stacked battery according to the correct polarity, close the bottom cover until it is locked 2. Connect the lavalier microphone to the audio socket of the transmitter 3. Open the bottom cover of the receiver, insert a AA battery with correct polarity, close the bottom cover until it is locked 4. Plug the receiver into the microphone input port of the audio amplifier 5. Turn on the receiver switch 6. Turn on the transmitter switch and the indicator light is on. At this time, the receiver indicator light is on, indicating that the receiver has received the transmitters modulation signal. At this time, adjust the transmitters potentiometer knob and audio amplifier microphone volume level appropriately To achieve the best sound effect Precautions: 1. If the sound quality, volume is abnormal or the receiving distance is shortened, please check the battery level of the transmitter and receiver 2. If it still cannot be used normally, there is a small hole on the body of this receiver with a frequency fine-tuning capacitor inside, which can be adjusted carefully with a flat-blade screwdriver to return to normal 3. If the microphone is not used for a long time, the battery should be taken out to prevent the battery from degenerating and flowing and damaging the parts 4. When using multiple sets of microphones at the same time, be sure to choose different frequency machines 5. Suitable