This system works on UHF frequency brand, use PLL circuit. There are 256 frequencies for your option.

本机工作在UHF频率，采用PLL锁相环电路，预设256个可选择使用频率。

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U-7000 is a PLL Synthesized dual channel UHF wireless microphone system with 16 user selectable channels.

是一个相位锁定频率合成UHF双频道的无线话筒接收系统，具备16 个预设的互不干扰频道供选择。

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