Product Details  VHF wireless microphone/wireless microphone/microphone/professional vhf wireless microphone/wireless mic  This wireless system is suitable for karaoke and general PA applications. This system is engineered for enriched sound reproduction and has a highly steady operating distance. Provided with up to 40 different channels among the individual systems, this model is popular for installation in karaoke boxes. Other main features include: Operating at 200-270MHz VHF band effectively improves prevention from interference. Enhanced band-pass filters at higher and medium frequencies which effectively reduce interfering signals. Transmitter operatino in normal condition even with battery voltage down to 6V. LED indication when batteries become low, prompting the user to replace the batteries. Special circuitry designed to eliminate popping noise when turning the transmitters on or off. Quartz frequency stabiliser used to improve performance consistency. Audio signals compressed and then reformed to further reduction of noise and improvement of dynamic range. SPECIFICATIONS Work Frequency:200-270MHZ Frequency stability:0.05% with quartz controlled Modulation mode:FM Maximun deviation range:±KHz,with limiting compressor 0.5% Sensitivity:10/uv s/n=50db 100db 100db receiving distance:50-100