pulse code tube

例句：

1. 1. The pulse code tube is a device used in communication systems for transmitting signals over long distances.
   脉冲编码管是一种用于通信系统中，用于在长距离上传输信号的设备。
2. 2. In the field of radio engineering, pulse code tubes are commonly used for frequency modulation.
   在无线电工程领域，脉冲编码管通常用于频率调制。
3. 3. The pulse code tube was developed by Bell Labs in the 1940s and has since beenreplaced by more advanced technologies.
   脉冲编码管是由贝尔实验室在20世纪40年代开发出来的，并且已经被更先进的技术所取代。