短語詞組短語Frequency counter accuracy 頻率計算器精度frequency tracking accuracy 頻率跟蹤精度frequency readout accuracy 頻率讀出精度frequency measuring accuracy 測頻精度Frequency Display and Accuracy 頻率顯示及準確度frequency -measurement accuracy 測頻精度high accuracy frequency testing 高精度測頻equal accuracy frequency meter 等精度頻率計high accuracy frequency measurement 高精度測頻 返回 frequency accuracy