發送短信 : Novel use of relays in identifying frequency response points

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| || | || | || | ||  |__  //   /_   _//  /_   _// 
| || | || | || | ||    / //     -| ||-   `-| |,-  
| \\_/ || | \\_/ ||   / //__    _| ||_     | ||   
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  `---`     `---`    `-----`   `-----`     `-`'