固体元件已可以代替低功率三极管和五极管,但是它们代替不了在那些需要大功率、要求获得和显示图象或者要求特殊性能及在恶劣环境条件下工作的设备所应用的一些专用电子管。通过不断地进行研究,目前电子管能满足最先进的电子设备的需要。本文除叙述某些新进展外,大部分是叙述在民用雷达、电视和通讯方面的应用。 Solid components can already replace low-power transistors and pentodes, but they can not replace some of the specialized tubes used in devices that require high power, require images to be acquired and displayed, or require special features and work in harsh environmental conditions. Through continuous research, the current tube to meet the needs of the most advanced electronic equipment. In addition to recounting some of the new developments, most of this article describes the applications in civil radars, television and communications.