# Electrical Engineers, Proceedings of the Institution of

## Filter Results

Displaying Results 1 - 25 of 36
• ### Low-noise travelling-wave tubes

Publication Year: 1970, Page(s):285 - 294
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Following the development of the earliest low-noise travelling-wave tubes, some 20 years ago, there was a period of great activity in this field. Until about five years ago, a great deal of work was published both on the theoretical aspects of low-noise behaviour, and on the attainment of low noise factors under laboratory conditions. Since then, the major effort has been directed towards translat... View full abstract»

• ### Current limitation through single-hole grids in a mercury-arc discharge

Publication Year: 1970, Page(s):295 - 302
| | PDF (985 KB)

Measurements are reported on current limitations induced by single cylindrical-hole grids in mercury-vapour valves. It is shown that, over a wide range of time scales, a single equation may be used to predict the onset of chopÂ¿ for a variety of current waveforms. The values of the two parameters in the equation are estimated for grids of different diameters and depths. The neutral-number density... View full abstract»

• ### Experimental computer for schools

Publication Year: 1970, Page(s):303 - 312
Cited by:  Papers (1)
| | PDF (1466 KB)

The computer is a small desk-top machine designed for teaching schoolchildren how computers work and how to use them. It works in decimal notation and has a powerful instruction set which includes 3-address floating-point instructions implemented as extracodeÂ¿ subroutines. Addressing can be absolute, relative or indirect. For input it uses a capacitive touch keyboard, and for output and display,... View full abstract»

• ### Elimination of error from fully compelled interregister signalling

Publication Year: 1970, Page(s):313 - 320
| | PDF (843 KB)

The fully compelled signalling sequence is frequently used for interregister signalling in telecommunications. The sequence is reasonably reliable, but erors can be experienced when interruptions arise in the transmission path between registers. The paper examines every possible effect of line interruptions, and produces constraints which enable every source of error to be positively eliminated. T... View full abstract»

• ### Corrigendum: Echo suppressors for telephone connections having long propagation times

Publication Year: 1970
| PDF (68 KB)
• ### High-time-resolution swept-frequency microwave polarimeter

Publication Year: 1970, Page(s):321 - 326
| | PDF (830 KB)

The instrument, which was built for the study of solar radiation in the band 2Â¿4 GHz, is capable of measuring the intensity and state of polarisation of the received energy as a function of time and frequency. Energy is received by a 6ft-diameter, paraboloid reflector with a broad band feed. The receiving system consists of four superheterodyne receivers, from which the desired outputs are genera... View full abstract»

• ### Two channel method for measuring the current gain of transistors at high frequencies

Publication Year: 1970, Page(s):327 - 337
Cited by:  Papers (1)
| | PDF (1711 KB)

A method has been developed for measuring the common-emitter short-cicuit current gain of transistors at frequencies in the range 10Â¿500MHz. The measurement is made by comparing the voltage outputs of two parallel channels, one of which contains the transistor and a standard attenuator; at balance, the transistor gain equals the attenuator loss. The best absolute accuracy obtainable is within Â±0... View full abstract»

• ### Distortion and its compensation in a varactor-controlled frequency modulator

Publication Year: 1970, Page(s):338 - 342
Cited by:  Papers (1)
| | PDF (561 KB)

The nonlinearity of the voltage-frequenc characteristic of a frequency modulator is a factor of primary importance when designing, for example, high-quality modulators for large-capacity microwave links. The nonlinearities of a varactor-controlled oscillator are derived. A theory of various distortion-conpensation circuits is developed. Distortion compensation is applied to push-pull modulator, an... View full abstract»

• ### Equivalent transformation of nonuniform lossless lines and distributed RC networks

Publication Year: 1970, Page(s):343 - 348
| | PDF (830 KB)

The equivalence properties of nonuniform transmission lines with different parameter distributions are analysed in detail. Both LC(lossless) and RC lines are treated. The formulation adopted may be considered as an appilication of the method of spatial-variable transformation to differential equations that govern the transfer-matrix parameters of these lines. The principal result is an equivalence... View full abstract»

• ### Modified reciprocity theorem for bianisotropic media

Publication Year: 1970, Page(s):349 - 350
Cited by:  Papers (5)
| | PDF (242 KB)

A modified reciprocity theorem is formulated for general bianisotropic media through the definition of a complementary medium. A bianisotropic medium is one in which the field vectors D and H depend on both E and B, and a moving mediucm appears bianisotropic to the laboratory observer even if it is isotropic in its rest frame. The conditions under which the modified reciprocity relationship will h... View full abstract»

• ### Electronically controllable primary feed for profile-error compensation of large parabolic reflectors

Publication Year: 1970, Page(s):351 - 358
Cited by:  Papers (16)
| | PDF (1011 KB)

The paper shows that it is possible to compensate for the effects of mechanical profile errors in large parabolic reflectors, by means of a specially designed multielement feed array situated in the focal plane of the reflector. The factors relating the magnitude and period of these profile errors to the size and complexity of the compensating feed are discussed, and a novel method is described fo... View full abstract»

• ### Intermodulation distortion in f.m. f.d.m. trunk-radio systems in 2-path fading situations

Publication Year: 1970, Page(s):359 - 368
Cited by:  Papers (2)
| | PDF (1106 KB)

The intermodulation-noise performance of f.m. f.d.m. trunk-radio systems is examined in conditions of 2-path fading. By using a convolution series expansion for the demodulated-baseband output corresponding to the CCIR noise-test-signal input modulation, it is possible to calculat both the noise/power ratio and the baseband enhancements to be expected in systems of 960 and 1800 audio-channel capac... View full abstract»

• ### Finite-element methods for inhomogeneous waveguides

Publication Year: 1970
| PDF (117 KB)
• ### Compatible controller-motor system for battery-electric vehicle

Publication Year: 1970, Page(s):369 - 376
Cited by:  Papers (5)
| | PDF (900 KB)

The thyristor controller and the d.c. motor of a battery-electric vehicle are considered as a system. The advantage of combining a current-controlled chopper regulator, using digital techniques, with a laminated-field series motor is outlined, design criteria are suggested, and an experimental system is described. Performance measurements using specially developed wattmeters are presented, which s... View full abstract»

• ### Calculation of the angular back swing following a short circuit of aloaded alternator

Publication Year: 1970, Page(s):377 - 386
| | PDF (1281 KB)

The paper describes the development of a mathematical model which includes some of the phenomena commonly neglected in digital-computer studies. The model provides for the representation of damping more accurately than the simple method using a torque proportional to slip. For an even more accurate solution, it includes differential equations describing the variation of the flux linkages. Calculat... View full abstract»

• ### Contact problems in machines using thyristor-assisted commutation

Publication Year: 1970, Page(s):387 - 397
Cited by:  Papers (1)
| | PDF (1840 KB)

D.C. machines using thyristor-assisted commutation have reached a relatively successful stage of development. One of the most difficult, and not entirely unexpected, problems has been the appearance of black marks on the surface of the segmented rings or `commutatorÂ¿. These marks have been associated with the sudden passage of current through a brush when the thyristor connected to it is fired. T... View full abstract»

• ### Discussion on 'Investigation of the load-flow problem' and 'Bootstrap Gauss-Seidel load flow'

Publication Year: 1970, Page(s):397 - 400
| PDF (594 KB)
• ### Effective resistance and reactance of a conductor of trapezoidal cross-section placed in semiclosed slot

Publication Year: 1970, Page(s):401 - 408
| | PDF (794 KB)

The paper is an extension of a previous one and discusses the distribution of current in a conductor which has a cross-section in the form of a symmetrical trapezium and is placed in a slot with a narrow opening. An approximate solution is obtained by assuming that the upper and lower surfaces of the conductor are defined by concentric cylinders. It is found that the current density at any point m... View full abstract»

• ### Analysis of single-phase rectified thyristor-controlled load with integral-cycle triggering

Publication Year: 1970, Page(s):409 - 414
Cited by:  Papers (6)
| | PDF (571 KB)

A rectified-voltage waveform caused by integral-cycle triggering of thyristors is found to contain most subharmonics and harmonics, odd and even, from zero to infinity. For a control period (on-plus-off time) of T supply cycles, the lowest subharmonic has a frequency of 1/T of the supply frequency. Subharmonics and higher harmonics can have amplitudes exceeding that of the average load voltage, de... View full abstract»

• ### Logical design of branched l.v. distributors

Publication Year: 1970, Page(s):415 - 420
Cited by:  Papers (2)
| | PDF (693 KB)

An analytical method of calculating the optimum economic design of a continuously tapered, branched radial, l.v. distributor, under balanced-loading conditions, is presented, assuming that the voltage drop is the limiting factor. The principles used in the continuously tapered distributor are then applied to the design of distributors from standard cable sizes. A computer program is described whic... View full abstract»

• ### Digital-computer simulation of transients in h.v. d.c. convertors with harmonic filters

Publication Year: 1970, Page(s):421 - 430
Cited by:  Papers (2)
| | PDF (990 KB)

In the practical design of h.v.d.c. convertor installations, a thorough investigation should be made of all the possible component-overstressing situations that may arise for a variety of reasons. This may, for example, be attempted with a scaled-down model of the installation, although the component losses in such a model are usually excessive, and, consequently, measured peak overvoltages and ov... View full abstract»

• ### IEE East Midland Power Section: Chairman's address. H.R.C. fuses and their environments

Publication Year: 1970
| | PDF (102 KB)

First Page of the Article
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• ### Measuring accuracy of distance protection with particular reference to earth-fault conditions on 400kv looped-circuit interconnections

Publication Year: 1970, Page(s):431 - 438
Cited by:  Papers (1)
| | PDF (1059 KB)

The paper provides a detailed evaluation of the errors arising in the measurement of impedance by distance protection, when applied to 400kV double-circuit lines formed in the widely used looped interconnection. An accurate separation of the errors arising from primary-circuit interphase and intercircuit mutual coupling, nontransposition of phase conductors, and fault resistance, is developed; and... View full abstract»

• ### Influence of mutual coupling between parallel circuits on the setting of distance protection

Publication Year: 1970, Page(s):439 - 445
Cited by:  Papers (3)
| | PDF (892 KB)

The significant mutual-coupling impedances between the two circuits in double-circuit overhead-line construction are considered. The impedances measured by distance-protection relays are examined, both for stability for faults outside the protected zone and for operation for faults within the protected zone. This is done for different primary-system-circuit arrangements and for the condition where... View full abstract»

• ### Phase-sensitive detection applied to excitation control of synchronous motors

Publication Year: 1970, Page(s):445 - 447
Cited by:  Papers (1)
| PDF (469 KB)

## Aims & Scope

The Proceedings of the Institution of Electrical Engineers was published by the IET between 1963 and 1979.

Full Aims & Scope