resonant circuit type frequency indicator

例句：

1. 1.The resonant circuit type frequency indicator is used to measure the frequency of a particular signal.
   共振电路类型频率指示器用于测量特定信号的频率。
2. 2. The device's ability to accurately measure frequencies is crucial for its application in scientific research.
   该设备准确测量频率的能力对于其在科学研究中的应用至关重要。
3. 3.In this experiment, we used the resonant circuit type frequency indicator to detect the presence of an unknown frequency.
   在这个实验中，我们使用了共振电路类型频率指示器来检测未知频率的存在。