General Considerations in Regard to Specifications for Reliable Tubes

The urgent need to design and manufacture electron tubes which will give more reliable performance under the stresses imposed by complex military and industrial electronic gear demands a new approach to the objective of a more nearly perfect tube. The specification for such a tube should so accurately describe its characteristics that the finished product, manufactured in accordance with the description, will fully satisfy the needs of the equipment designer. It should also enable him to incorporate the tube into an assembly of a high order of reliability. Inspection and application manuals formulated in accordance with the same objectives, and definitely correlated with each other, should be considered as a part of the specification. The lot acceptance system, coupled with adequate sample size, is recommended as an integral feature of the proposed type of specification. Properly employed, it is more effective than 100-per cent screening, and also provides the manufacturer with incentives to build quality into his product. Life testing based on adequate sample size is also strongly recommended.