DOI:10.1049/ree.1967.0093

出版商:IERE    

年代:1967

数据来源: IET

摘要:

Although proposed in 1961, the nullator and norator have not been widely used or understood. At first sight these elements appear rather remote from reality, and in this paper an attempt is made to relate them to some practical devices. It is suggested that a nullator-norator pair (nullor) may be regarded as a reasonable idealization of a number of physical devices, but that the nullator and norator, considered individually, cannot be so regarded, and are not physically meaningful.‘Controlled-source’ behaviour can usefully be represented by nullors in conjunction with passive two-terminal elements, and by generalization of the nodal and loop methods of analysis to deal with networks containing nullors, this can result in significant simplification in the analysis of some active networks. Topological methods of solution may also be used.It is concluded that there are no outstanding difficulties involved in incorporating the nullor into the framework of conventional network theory, and that nullors may be useful in the analysis of practical active networks.

DOI:10.1049/ree.1967.0095

出版商:IERE    

年代:1967

数据来源: IET

摘要:

This paper discusses applications where automatic testing can be a requirement, some of the advantages and disadvantages to both manufacturer and customer, and the demands its use makes upon the aircraft electronic equipment designer.Some of the problems which exist at present are due to the lack of consideration given to the use of automatic testing by the equipment designer. These can be overcome in the future if design, production and test methods are organized to take proper account of them. The constraints that these requirements place on the design processes are discussed.

DOI:10.1049/ree.1967.0096

出版商:IERE    

年代:1967

数据来源: IET

摘要:

Consideration is given to the design problems of low-cost f.d.m. systems which achieve economy by the avoidance of band-pass filters for each channel at both ends of the system. It is shown that the best basis of design is the use of constant-resistance modulators.

DOI:10.1049/ree.1967.0097

出版商:IERE    

年代:1967

数据来源: IET

摘要:

Field strength measurements were made over several overland transmission paths on Bands I and II, at distances up to 274 km. The measurements when corrected for transmitting aerial height above mean terrain and also for receiving site variation factor give field-strength/distance curves which are in reasonable agreement with the current C.C.I.R. tropospheric propagation curves. The range of fading and field strength exceeded in each month for specified time-percentages are also discussed.

DOI:10.1049/ree.1967.0098

出版商:IERE    

年代:1967

数据来源: IET

摘要:

The layout and construction of a typical second-generation digital computer is outlined, and an account given of the manual methods of assembly and testing in use until comparatively recently. The feasibility of introducing automation techniques is discussed, and an analysis made of those areas of production and testing most amenable to such treatment. Three applications are described, demonstrating the direct application of automation to the processes of wiring, logic-card testing and final commissioning, emphasizing the dramatic reduction in manufacturing time-scale made possible by the resulting increases in production efficiency and machine reliability.

DOI:10.1049/ree.1967.0099

出版商:IERE    

年代:1967

数据来源: IET