|
|
| 1. |
A new frequency-comparsion circuit for the cathode-ray tube |
| |
Journal of the Institution of Electrical Engineers - Part III: Communication Engineering, including the Proceedings of the Wireless Section of the Institution,
Volume 89,
Issue 8,
1942,
Page 191-194
G.H.Rawcliffe,
Preview
|
PDF (459KB)
|
|
摘要:
A new method of producing a re-entrant trace tor frequency comparison on a cathode-ray tube is described. Formulae are deduced for complex frequency ratios, and the magnitude and direction of “drift,” when the frequency ratio is not exact, are investigated. A note on the direction of rotation of a circular time-base is added.
DOI:10.1049/ji-3-1.1942.0028
出版商:IEE
年代:1942
数据来源: IET
|
| 2. |
The comprehensive assessment of telephone communication efficiency |
| |
Journal of the Institution of Electrical Engineers - Part III: Communication Engineering, including the Proceedings of the Wireless Section of the Institution,
Volume 89,
Issue 8,
1942,
Page 195-206
J.R.Hughes,
Preview
|
PDF (1831KB)
|
|
摘要:
The Introduction defines the problem under discussion and distinguishes between subjective, objective and semi-objective tests. The author then considers subjective telephone tests in greater detail, and emphasizes the importance of testing for “fitness for purpose” under conditions similar to those of practical use. There follows a discussion of the application of the results of subjective tests to practical cases, in the course of which the arguments are put forward for the statistical extension of the results of immediate-appreciation tests. An account is then given of the application of the statistical technique to immediate-appreciation tests, and the author concludes with some suggestions as to how the effects of speaking-end room-noise may be included in the statistical technique. A short bibliography is appended.
DOI:10.1049/ji-3-1.1942.0029
出版商:IEE
年代:1942
数据来源: IET
|
| 3. |
Fluctuations in space-charge-limited currents |
| |
Journal of the Institution of Electrical Engineers - Part III: Communication Engineering, including the Proceedings of the Wireless Section of the Institution,
Volume 89,
Issue 8,
1942,
Page 207-212
D.A.Bell,
Preview
|
PDF (802KB)
|
|
摘要:
The paper shows that the fluctuations in the anode current of a space-charge-limited valve can be calculated in a manner exactly similar to the calculation of the thermal agitation noise in a metallic conductor, in terms of the electron transits. Corresponding values of the noise ratio, or “smoothing factor,” are derived; they are found to be in agreement with experimental data from a variety of sources. The ratio is a function ofeV/(kθ), and is only slightly dependent upon the ratio of anode diameter to cathode diameter of the valve.
DOI:10.1049/ji-3-1.1942.0030
出版商:IEE
年代:1942
数据来源: IET
|
| 4. |
The measurement of the characteristics of concentric cables at frequencies between 1 and 100 megacycles per second |
| |
Journal of the Institution of Electrical Engineers - Part III: Communication Engineering, including the Proceedings of the Wireless Section of the Institution,
Volume 89,
Issue 8,
1942,
Page 213-220
T.Iorwerth Jones,
Preview
|
PDF (1052KB)
|
|
摘要:
The paper gives a detailed discussion of the technique of the measurement of the characteristics of cables by the familiar open-end and closed-end method. It is illustrated by reference to the use of the N.P.L. dielectric test-set for those measurements, but is of general application to all measurements made by connection of the cable as a shunt circuit to a closed tuned circuit, with reactance variation as the basis of measurement. The paper is based on practical experience in this work and is intended as a guide for any who have occasion to make this type of measurement.
DOI:10.1049/ji-3-1.1942.0031
出版商:IEE
年代:1942
数据来源: IET
|
|
首页
