Acceleration Effects on Electron Tubes

The rapid expansion of the use of electronic equipment by industry and the armed services has created increasingly new demands on both the electrical and mechanical characteristics of electron tubes. Since these tubes are electronic devices, it is only natural that their structural designs are dictated to a large extent by electrical requirements. However, the experience gained with conventional tubes in some of the new equipment applications has revealed certain mechanical shortcomings which reflect on the proper functioning or life of the tubes. The realization of the increasing importance of mechanical design has resulted in an increased effort for structural improvements to assure more reliable tube performance. The term "reliable", as used here, denotes that a tube has a high degree of dependability when subjected to specific conditions, either electrical or mechanical. Thus, the requisites for reliability may differ for various applications. Although, in designing a tube, many requirements must be taken into consideration, only some of the problems connected with dependable tube performance under mechanical disturbances, i.e., shocks and vibrations, will be discussed here. Since the performance of a tube depends on the geometry of its component parts, minute changes in element spacing may produce variations in its characteristics. Because of the necessarily delicate structure of some tube elements, permanent or transient dimensional changes may be produced by mechanical forces acting on the tube unless the tube is 1203