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供应SW—1B型超声-声速测定仪 一台起订5位数显直尺手动测距、优质压电换能器、换能器谐振频率、有效测距长、读数精度高。选购配套仪器：示波器、DCY-3D型功率函数信号发生器。适用：物理、高教 、普教
