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- frequency exchange signaling 频率交换信号
- frequency exchange signalling 换频传信
- centralized inter exchange signaling 集中局间信令
- exchange signaling transfer delay 交换机信令传送时延
- The two ships gradually drew together until they were near enough to exchange signals. 两船渐渐驶近，直到它们能互相交换信号。
- The two ships gradually drew together until they were near enough to each other to exchange signals. 两艘船逐渐靠拢到可以相互打信号的距离。
- Two hours later a large steamer exchanged signals with them. 两个钟头以后，一艘大轮船和他们交换了信号。
- Promote friendship and goodwill to DX contacts. Look for ways to get to know each other rather than simply exchanging signal reports and 73s! 用远程通讯促进友谊和诚信。用各种方法增进彼此的了解,而不要仅仅交换信号报告和73;
- He varied the transmission frequency. 他变换了无线电传送的频率。
- A unit of frequency equal to one cycle per second. 赫兹频率的单位，等于每秒一周
- A filter whose transfer function is matched with the frequency spectrum function of input signal. 其传递函数与输入信号的频谱函数相匹配的一种滤波器。
- exchange signalling transfer delay 交换机信令传送时延
- An electronic device that converts one frequency of a radio signal to another. 变频器将无线电讯号从一种频率转换成另一种频率的电子装置
- Fatal accidents have decreased in frequency over recent years. 近年来死亡事故发生的频率已经下降。
- We can often correlate age with frequency of illness. 年龄的大小往往与发病率有关。
- Accidents on that highway are happening with increasing frequency. 那条高速公路上车祸发生得越来越频繁。
- In electronics, undesirable low frequency currents interfering with a desired signal, and usually caused by a poorly screened alternating mains supply. 在电子学领域，一种不希望发生的低频电流，它干扰所要求的信号。通常这种现象是由于交流供电线路屏蔽不良引起的。
- He tuned his radio to the police frequency. 他把无线电调到警方的频率。
- This radio signal has a frequency of 800000 cycles per second. 这个无线电讯号的频率是每秒八百千周。
- exchange signaling unit 交换机信令单元
