Electronic Tubes

Abstract

This chapter is concerned only with tubes used in professional equipments ie transmitters, radar, and instruments, it does not deal with domestic tubes mass produced for broadcast and television receivers, or home sound reproduction equipment. The performance, including reliability, of such tubes is well established and their application understood and standardised. The tubes classed as professional are likely to be used for the whole of the century, often as the only non-solid-state device in an equipment. The production rate of such tubes is low when compared with domestic types, often only a few hundred a year, and production runs are often short. It is, therefore, more difficult to make statements of reliability which are well supported by test data, such as life tests, particularly when the assessment is made by means of a destructive test.