Description:Several new domestic unique technologies are added on the basis of the original microphone technology, which makes the system have ultra-high sensitivity, strong anti-interference ability and good stability. The original technology includes high-efficiency low-cost RF emission technology and SMT production process in the United States, and uses a locking frequency of better than 10ppm quartz crystal, dynamic audio compression, expansion circuit, image frequency suppression circuit, switch-time shock elimination circuit, anti-return circuit variable output control technology, computer EDA, analog online auxiliary design, etc.Features:The system have ultra-high sensitivity, strong anti-interference ability and good stability because several new domestic unique technologies are added on the basis of the original microphone technology. It can be used as soon as it is booted because the frequency point is fixed, more convenient.The volume of four channels is independently adjustable, which provides 1+4 audio output, and the four-channel audio output is independently controllable.The conference/handheld/collar clips in the transmitter can be mixed and matched to use.Stackable machine, 5 sets of different frequency points can be used at the same time.Specification:Name: UHF one for four professional wireless lapel microphonePlug: US Plug / UK Plug / EU Plug (Optional)Model: UF-4000Battery: AA x 2 (not included)Frequency Range: UHF 642.2~660.8MhzTransmit Power: <30mW (according to the applicable country specification)Harmonic Power: <40dB (main wave)Battery Life: >10 hoursOscillation Mode: Quartz crystal oscillationStability: 10PPMWireless Interface: BNC/50Maximum Frequency Offset: 50KHzSignal to Noise Ratio: >105dBDistortion: <0.5%@1KHzImage Interference: >85dBAdjacent Rrequency Interference: >75dBFrequency Response Range: 60Hz~16KHzSquelch Control Mode: Multiple squelch circuitMaximum Output Level: +10dBVSensitivity adjustment range: 12-32 dBVPower Supply: External DC power supply, 0.4A, 12~15V DCUse Distance: Open environment: 50-80m / 164-262ft, complex environment: 30-40m / 98-131ftHost Size: Approx. 48x19x4cm / 18.9x7.5x1.6in Package List:Transmitter x 1Receiver x 4Antenna x 2Manual x 1Audio Cable x 1Power Adapter x 1Lapel Microphone x 4.