Century Accessory 14.37 inch Photography Camera Camcorder Uni-Directional System Condenser Shotgun Interview MIC Microphone for Canon Nikon Sony Olympus Pentax Panasonic and Other HD SLRS DV Camcoders Switch on. Push the switch to 'TELE' for short distance application or to 'NORMAL' for long distance application Follow signs "+","-", batteries are installed correctly, and connect the audio output line First, the amplifier volume is controlled in the "0" position. Then turn on the amplifier and the microphone, adjust the volume slowly until achieve the best The best effects of pickup is away from the microphone head 30cm