YELANGU YLG9929B MX4 Dual-Channel 100CH UHF Wireless Microphone System with 2 Transmitters and Receiver for DSLR Cameras and Video Cameras(Black) Features 1. Dual-channel UHF line receiving technology, supporting 2 transmitters to work. 2. Using secondary DSP receiving processor, strong anti-image interference ability. 3. Professional circuit design with LOW-CUT function. 4. Provide Mono stereo output and Stereo mono output. 5. Equipped with a headphone interface, which can be connected to headphones to monitor the radio effect in real time. 6. The volume of monitoring and audio output can be adjusted independently, and has a memory function. 7. Adopt WNCRS acoustic environment noise reduction technology, which can suppress environmental noise and wind noise. 8. Integrate a high-performance audio expander to provide a wider audio real-time dynamic response. 9. Provide 100 wireless channels, you can set multiple groups of channels to work at the same time. 10. Support Line in MIC in input, Line in is linear input, MIC in is microphone input. 11. It supports charging with a camera, with a charging current of 600mA. Specifications 1. Frequency response: 30Hz-18KHz 2. Delay of sound transmission: <0.15 ms 3. Microphone specifications: Capacitive omnidirectional 4. De-emphasis: 50uS 5. SN ratio:>90 dB 6. Maximum frequency deviation: +-50 kHz 7. Mute level: 15 dBuV 8. Distortion: >0.9% 9. Number of channels: 100 10. Indicator: RF, IR 11. Audio output: level> 48 dBV 12. Reference distance: 60 meters (outdoor open area) 13. Audio output interface: 3.5 mm jack 14. Antenna: 14 wavelength spring antenna (adjustable angle) 15. Headphone output: level 15mW (16 ohm) 16. Power: 2.4V DC (2 AA rechargeable batteries) or 3.0 V DC (2 AA alkaline batteries), battery not included, 5.0 V DC (external USB mobile power supply) to charge the rechargeable batteries, current: 600mA 17. Battery life: Taking 2 AA rechargeable batteries 3200mAh as an example, Group A+B can be used for about 8 hours at the