frequency-shift keyer

例句：

1. 1. The frequency shift key is used to adjust the signal's frequency.
   频率偏移键用于调整信号的频率。
2. 2. The frequency shift keyer was designed to improve the accuracy of frequency measurements.
   频率偏移键器被设计用来提高频率测量的准确性。
3. 3. The frequency shift keyer has been widely used in various industries for its ability to accurately measureand control frequencies.
   频率偏移键器在各个行业中被广泛使用，因为它能够准确地测量和控制频率。