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A method of comparing the basic performance of electron guns is described. The method is applied to some recently computed results on two versions of an electron gun which has a hairpin-filament cathode.
In an interesting and useful paper by Worster (1979 a), hereafter referred to as JW, computed results are given relating to two electron guns. When the performance of the guns was compared it was concluded that one gun was better than the other in all respects. However, in making the comparison the electron beam divergence was not taken into account. Although the method of comparison used in JW may, of course, be satisfactory for some purposes, the computed results in JW are comprehensive enough to provide information for an alternative method of comparison which includes beam divergence. Such an alternative method, described in this note, leads to different conclusions. [ABSTRACT FROM AUTHOR]

Comments concerning on inconsistencies in the analysis of alpha-particle scattering. Validity of the field concept; Relation between the laws of physics and relativity; Information on the theory of electromagnetic.

Presents a reply on the inconsistency in the analysis of alpha-particle scattering. Correlation between electromagnetic field and vectors; Analysis of the geometry of vector functions; Distinction between motion and force.

To determine theoretically whether or not a positive column is stable requires a complete description of the energy balance, and hence precise knowledge of all excitation, ionization and other loss mechanisms. If such a description were available it would indicate either that the plasma is d.c. stable, i.e. perturbations tend to be damped, or that its equilibrium is one in which oscillations are present. In either case, it is to be expected that, the steady-state conditions obey the 'minimum energy' principle, as pointed out by Professor Hoyaux.
The purpose of our article was to show that both the experimental evidence, and the inferences to be drawn from knowledge of the relevant collision processes, indicate that the mercury-vapour positive column can be d.c. stable. The low-frequency oscillations commonly observed, and the more rarely observed high frequency ones, can be identified as originating in the cathode region. They propagate with damping along the column. By increasing the length of the column, the amplitude of these damped oscillations may be decreased indefinitely, far from the cathode.
It is certainly true in other gases, which exhibit standing or moving striations, that the uniform column is unstable against the perturbation corresponding to the striations, the stability being determined by the form of the relevant, collision cross-sections and we have no doubt that Steenbeck's principle would reveal, for such gases, that the striated . column has a lower average voltage drop than the uniform column. This is no reason, however, to attribute to plasma an evil genius for finding modes of instability. Plasmas are only as inventive as the laws of physics allow. Professor Hoyaux's 'guess' as to the ability of a mercury-vapour plasma always to succeed in finding an unstable mode of operation is no substitute for experiment and analysis. [ABSTRACT FROM AUTHOR]

Comments on the possibility of mercury vapor column existence on random process. Assessment on the stability of the column; Examination on the voltage drop of the oscillation; Effectivity of the Maxwellian distribution of electrons.

This paper describes a hardware implementation of a two-way converter logic by which conversion between numbers from positive to negative binary representation is possible. Index terms : (i) Negative radix, (ii) Positive radix, (iii) Two-way conversion.
The present paper describes a hardware implementation of a slight modification of a scheme earlier presented by Krishnamurthy (1971). The interesting feature is that this converter can take an input (or give an output) in positive or 2's complement positive binary form as compared to the sign magnitude form by Zohar (1971). For carrying out two-way conversion, it is sufficient to switch a single level to a high or a low. [ABSTRACT FROM AUTHOR]

A new open circuit step cavity resonator for continuous and contactless monitoring of sheet moisture content is proposed. The return loss as well as the perturbation in the resonant frequency of the resonator due to variations in the moisture content of sample paper passing through the cavity are monitored in real time by terminal devices and interpreted to display the paper moisture content in digital or analog form. [ABSTRACT FROM AUTHOR]

In this paper we investigate the multi-stable transistor circuits of which basic operation can be regarded as threshold logic. The sensitivity analysis on the actual circuits is also considered as well as their logical behaviour.
The multi-stable circuits are usually constructed from the flip-flop circuits which have basically two transistors. The transistor, however, can be regarded as a comparator whose output ('0' or '1') depends on whether the input level is higher than a reference (including the insensitive region) or not. Hence, combining it with an adder circuit, each input of which is multiplied by some factor, the circuit operates as a threshold device (Hampel and Winder 1971).
In this paper we investigate these problems and suggest that the network constructed from n threshold devices is useful only as an n-stable circuit. [ABSTRACT FROM AUTHOR]

The paper is an extension of the authors' previous work on travelling-wave circular loop and helical antennas immersed in an isotropic compressible electron plasma. In the present paper the expressions for the electromagnetic and electroacoustic components of the radiation field and of radiation resistance in the case of an electrically large multi-turn circular loop antenna in plasma having a travelling-wave current distribution are derived. Finally, treating the multi-turn loop in vacuum as a particular case of the general results for the same in a plasma medium, expressions for electromagnetic field and radiation resistance have been obtained for different loop sizes and the number of turns in it. It is shown that its field and the radiation resistance, both in plasma and in vacuum, are seriously affected by the number of turns in the loop and under certain conditions much higher values of radiation resistance can be obtained. [ABSTRACT FROM AUTHOR]

The paper deals with parametric phenomena in a non-linear oscillating circuit with negative resistance. The differential equations of the parametric excited circuit, for the case where the self-oscillations' amplitude is smaller than the amplitude of the pumping signal, reduce to the equations of Hill and are solved by an original method (Samoylo and Spasov 1970). In an investigations of the transient and steady-state regimes the real non-linearity of the reactive element in the oscillating circuit is considered. The mode of forced oscillations and the resonance of the second and third subharmonics of the pumping signal are discussed. The experimental results agree well with theory.
The results given in the paper may be of interest in an investigation of oscillating circuits, utilizing semiconductor elements with negative resistance : tunnel diodes, Gunn diodes, avalanche transit-time diodes, etc. [ABSTRACT FROM AUTHOR]

A new static distance relay working on the principle of sequence detection is reported in the paper. The three-input sequence detector developed in the paper is simple and convenient to employ in obtaining the popular quadrilateral characteristic. The relay employs semi-conductor devices throughout and operates in less than a cycle.
The E.H.V., long, heavily loaded transmission lines are usually protected by means of distance relays. A static distance relay employing phase comparator may either work on the principle of cosine comparison (Adamson and Wedepohl 1956, Humpage and Sabberwal 1965) or sine comparison. The principle of sequence detection is reported by Thakkar and Parathasarathy (1970) where it is shown that the required characteristic may be obtained by detecting the sequence of the selected mixed signals. Thakkar and Parathasarathy (1970) further present the mathematical basis of the relay working on the principle of sequence detection and describes two schemes of practical circuitry of the relay. It is necessary to employ separate phase comparator for every pair of input signals in the first scheme resulting in the costly construction of the relay. The second scheme employs flip-flop circuits in the detection of the sequence requiring less number of circuit components. However, it suffers from the disadvantage that its time of operation increases unduly to two cycles. [ABSTRACT FROM AUTHOR]

This paper presents a new method of realization of second-degree filters having low-pass, band-pass and high-pass characteristics. Each of the characteristics requires two unity gain non-inverting type amplifiers in addition to passive resistances and capacitances. Details of sensitivity analysis have been reported. This method of realization gives appreciably low Q sensitivity due to the variation of passive elements. But the Q sensitivity due to the variation of the gain of the amplifier becomes a little high. This limits its application in high-Q filters.
This paper gives a new realization procedure for active second-order filters. Each of the band-pass, low-pass and high-pass characteristics requires two unity gain non-inverting amplifiers in conjunction with the passive resistances and capacitances. Details of sensitivity analysis show that the percentage variation of pole Q due to the percentage variation of passive R and C is sufficiently low. But the Q sensitivity due to the variation of amplifier gain is a little high. This dictates that the method will be practically useful in the case of low-Q filters. [ABSTRACT FROM AUTHOR]

In this paper the recently developed theory of complementary variational principles is extended to include constraints. The theory is applied to electrostatic fields where the constraint corresponds to the specification of the total charge on a conductor.
In a recent paper (Arthurs and Robinson 1969 b), maximum-minimum principles for boundary value problems in electrostatics and magnetostatics were derived from the theory of complementary variational principles. For the simplest electrostatic case, extremum principles were found for the Dirichlet problem:
The purpose of this proper is to derive extremum principles for constraint problems in electrostatics of the form:. [ABSTRACT FROM AUTHOR]

In this paper, the dispersive behavior of non-linear magneto-optical susceptibilities which describe the self-induced effects in n-type semiconductors is studied. The theory can be successfully applied to InSb and InAs, taking into account the most important sources for the conduction band electrons' contribution to the non-linear susceptibilities: the kp interaction between the conduction and valence bands, and the energy dependence of the relaxation time.
Recently, the study of the dispersive behavior of non-linear optical susceptibilities has been considered an appropriate method for treating the electronic structure of solids, facilitating the production of some opto-electronic devices. [ABSTRACT FROM AUTHOR]

To discuss the small amplitude disturbances propagating through a hot plasma in a uniform magnetic field, or to find the macroscopic quantities of a plasma, it is necessary to solve the Vlasov equation. In this paper a general vector method is presented and it will give a solution of the linearized Vlasov equation with a collision term. The explicit expressions of the perturbed distribution functions for both anisotropic and isotropic equilibrium distributions are derived. The results can be easily applied to find the dispersion equation and the polarization properties of the waves.
In recent years numerous studies have appeared in the literature concerning the high frequency properties of a plasma immersed in a static magnetic field. Such studies are significant in providing the basis for predicting the electromagnetic wave propagation and absorption in the ionosphere, and for explaining the origin of solar radiation, as well as the microwave diagnostic of plasma in thermonuclear reaction, etc. (Gross 1951, Sitenko and Stepanov 1957, Bernstein 1958). When the thermal velocities of the particles are negligible, or when the zero wavelength approximation is valid, the magneto-ionic theory gives a satisfactory treatment of waves in a plasma. However, if the effects of random thermal motions of the particles have to be considered, the kinetic theory will then become a necessity in our discussion. It not only offers a more complete and rigorous description of the plasma but also allows one to see which part the individual particle plays in sustaining the oscillation. The fundamental problem in the kinetic theory is to solve the Vlasov equation for a distribution function which can then be used to determine either the conductivity tensor and the dispersion equation or other macroscopic quantities of the plasma. Our objective in this paper is to present a vector method and to derive an explicit general solution of Vlasov equation. [ABSTRACT FROM AUTHOR]

The phenomenological theory of the electrodynamics of stationary material media was formulated by Maxwell. To allow a unique determination of the field vectors Maxwell's equations have to be supplemented by constitutive relations which describe the behaviors of the media under the influence of the field. The purpose of the present paper is to extend Minkowski's theory of a moving isotropic medium to include a gyro-electric magnetic medium. The properties of a transformation matrix are discussed first. Three sets of constitutive relations depending on the choice of independent field vectors for a moving gyro-electric magnetic medium are then derived explicitly. Maxwell's equations, together with the constitutive relations, thus form a complete theory of the electrodynamics of a moving gyro-electric -magnetic medium. With the properties of the transformation matrix stated in the paper, the results can be easily extended to an arbitrarily anisotropic medium. Some of the special cases previously treated by other authors are also considered. [ABSTRACT FROM AUTHOR]

Many previous authorities have pointed out the potential advantages of threshold logic gates in comparison with Boolean gates in reducing the gate population per given system (Dertouzos 1965, Lewis 1967, Hurst 1972 a). All these previous comments on population reduction were made without considering the above additional factor of hazard-free realization.
This paper, however, shows that when hazard-free realizations are sought, a further advantage of using threshold gates accrues. The feature that the logic selection of a threshold gate is not a simple rectangle on a Karnaugh-map layout, but rather can be an irregular shape, is a very powerful tool for generating hazard-free networks. Thus an even greater potential saving in gate population per system is generated in this situation, in comparison with a hazard-free Boolean system. Many previous authorities have pointed out the potential advantages of threshold logic gates in comparison with Boolean gates in reducing the gate population per given system (Dertouzos 1965, Lewis 1967, Hurst 1972 a). All these previous comments on population reduction were made without considering the above additional factor of hazard-free realization.
This paper, however, shows that when hazard-free realizations are sought, a further advantage of using threshold gates accrues. The feature that the logic selection of a threshold gate is not a simple rectangle on a Karnaugh-map layout, but rather can be an irregular shape, is a very powerful tool for generating hazard-free networks. Thus an even greater potential saving in gate population per system is generated in this situation, in comparison with a hazard-free Boolean system. [ABSTRACT FROM AUTHOR]

In a recent paper, Seth has pointed out the error in the derivation of the adjoint model of Director and Rohrer and has given the correct results which are applicable for time-domain analysis. This fact calls for a re-examination of the results obtained from considerations of inter-reciprocity between the sensitivity network and the adjoint network. The purpose of this paper is first to develop the sensitivity model in its most general parametric form and then establish a link with the corrected adjoint model through the use of the inter-reciprocity theorem. [ABSTRACT FROM AUTHOR]

Two different algorithms are presented to design lossless ladder filters. Both methods are developed from a characteristic equation of the filters. The first method defines a performance index J and, using the special properties of the formulation used, evaluates the gradient of J with respect to element values. Optimization routines are then used to obtain element values to give the desired response. The second method starts with the characteristic equation and obtains a set of algebraic equations to evaluate the errors in the element values. Using this information, element values are adjusted to obtain the desired filter.
In this paper different algorithms for computer-aided design of ladder filters are given. Two examples serve to illustrate the power of the method. The methods have proved to be practical and save a lot of engineering time which is needed to design general parameter filters using the curves and tables which have been supplied by Cauer and others. This paper also gives
an added importance to eqn. (15) which has not been used very often by filter designers. The methods are applicable for lossy filters as well. Modifications are needed only on eqns. (25) and (26). [ABSTRACT FROM AUTHOR]

In this paper the dispersion relation for rectangular waveguides filled with homogeneous lossy drifting plasma under the influence of infinite longitudinal magnetic field is derived and discussed. The properties of TE modes are found to be the same as those of air-filled guides. However, uniaxial anisotropic drifting lossy plasma has a significant effect on the propagation characteristics of TM modes. A comparison of the effects and physical significance of the changes duo to isotropic and anisotropic plasma models is discussed.
1. Introduction
In recent years plasma-filled waveguides have received considerable attention owing to their applications in microwaves. A general solution for the propagating modes in waveguides completely or partially filled with plasma, taking into account an applied static magnetic field, non-uniform density over the guide cross section and non-vanishing temperature, has not yet been found. It is customary to incorporate the effect of plasma by assuming either an equivalent dielectric constant in the absence of an external magnetic field or an equivalent dielectric tensor with an external applied magnetic field. The nature of electromagnetic wave propagation in waveguides filled with cold stationary plasma under the influence of an external magnetic field was the subject of extensive investigation (Allis et al. 1963). Recently Tuan (1969) and Kalluri (1970) have given some idea of the propagation of electromagnetic waves in waveguides filled with warm and drifting plasma. It is the purpose of the present paper to study the dispersion relation in rectangular waveguides filled with homogeneous drifting lossy uniaxial anisotropic plasma. The strong static magnetic field is assumed to be in the direction of the guide axis. [ABSTRACT FROM AUTHOR]

The state variable analysis of modulation rate distortion as a degradation of pure FM signals is discussed by Lie algebraic methods. Use is made of the Wei-Norman basis development for the exponential representation of the modulation and distortion in terms of a finite matrix product. An outstanding feature of this paper is the representation of the instantaneous rate distortion as an implicit function of the relative phase distortion. Two particular examples which are characteristic of important classes: of frequency modulators are presented to illustrate the analysis. [ABSTRACT FROM AUTHOR]

The role of orthogonal polynomials m obtaining a transfer function whose magnitude or phase approximates that of the ideal low-pass filter characteristic is well recognized. In this paper an attempt is made to generate positive real functions starting from the recurrence relations which are normally used in generating polynomials.
The importance of orthogonal polynomials in approximating a specified frequency response characteristic is well known. For instance, Chebyshev polynomials have been used in deriving a transfer function whose magnitude approximates that of an ideal low-pass filter. Also, the phase of the transfer function given by the inverse of a Bessel polynomial is shown to approximate that of an ideal low-pass filter. Though several polynomials have been successfully used to obtain required transfer functions, no attempts seem to have been made to use them for the generation of positive real functions. In this paper an attempt is made to generate positive real functions starting from the recurrence relations that are usually employed in the generation of polynomials. [ABSTRACT FROM AUTHOR]

In a series of papers and reviews Melehy (1964, 1965 a, 1965 b, 1966, 1968, 1970) has proposed an approach to thermodynamics via a somewhat unique definition of equilibrium, and in particular has illustrated his model by an examination of the equilibrium and steady-state conditions in semiconductor p-n junctions.
It is the purpose of the following paper to re-examine Melehy's hypotheses and to show that where his conclusions differ from those more generally accepted that it is due to misconception of semiconductor device principles. [ABSTRACT FROM AUTHOR]

In this paper a method of drawing the signal flow graph of an active degenerate RLC network is given. From this signal flow graph the state equations of the network are obtained using Mason's graph gain formula.
The representation of networks in state equation form X(t) = AX(t) + But is advantageous in many respects. Recently Acar (1970) has provided a simple method for the formulation of state equations of active non-degenerate RLC networks using signal flow graph. The method is computationally more simple than earlier methods due to Dervisoglu (1964) and Kuh and Rohrer (1965), but unfortunately this cannot be applied for networks containing degeneracy. The purpose of the present paper is to provide a method for drawing the signal flow graph of an active RLC network containing degeneracy in the form of capacitance loops and inductance cutsets. By eliminating the dynamically superfluous variables with suitable linear equations of constraint due to degeneracies, the signal flow graph of the network may be properly drawn. By inspection of this signal flow graph the A and B matrices are directly obtainable using the graph gain formula. [ABSTRACT FROM AUTHOR]

The paper presents an active RC network which exhibits selective, all-pass and notch characteristics with simple adjustments of parameters. Two gain-parameters and passive-resistive elements are kept adjustable for this purpose, which also help to obtain variable selectivity and desired center frequency of the filter in the appropriate configurations. Discussions on the Q factor sensitivity of the filters have also been appended.
This paper describes an active RC second-order filter which can be adapted to operate in three different modes. As a band-pass filter it can be designed to have adjustable bandwidth and center frequency, which shows that the circuit may be used as a tuned selective filter. Secondly, depending on the choice of the system parameters, the circuit behaves as an all-pass network with adjustable delay. Finally, it is shown that the circuit operates as a very good rejection filter having continuously adjustable selectivity and notch frequency with no change in the shapes of its transmission characteristics. [ABSTRACT FROM AUTHOR]

The paper describes a circuit containing a junction transistor and a F.E.T. which behave as a one-port voltage controlled negative resistance of adjustable magnitude.
One-port negative resistance circuits, being very useful in synthesis of network functions, filter design and the design of regenerative circuits, have been developed by many authors (Waldmann and Beiri 1955, Indiresan 1959, Nagata 1965, Martinelli 1966). In this paper a new voltage controlled negative resistance circuit employing a transistor and a F.E.T. has been proposed which is different from the existing circuits regarding its network topology. The circuit requires no internal bias. As this circuit utilizes one transistor and a F.E.T., the circuit can be readily fabricated as an integrated module. [ABSTRACT FROM AUTHOR]

When harmonic oscillators utilizing elements with N-type and S-type voltage/current characteristics (elements with negative conductance or negative resistance) are calculated, usually only the non-linearity of the voltage/current characteristic is taken into account. However, the impedance of these elements is of a complex character, and the non-linearity of the reactive component influences the different modes of operation. This influence may be considerable and in some cases even dominating. If, however, it is taken into account, then the calculation of such systems becomes very difficult. The method used in this paper (Samoylo 1964, 1968) enables these problems to be treated correctly and at the same time considerably simplifies the mathematical calculations.
The results given in the paper may be used when harmonic oscillators utilizing tunnel diodes, Gunn diodes, avalanche diodes, avalanche transistors, unijunction transistors, p-n-p-n-type elements, etc., are studied.
The calculations are made considering the non-linearity of the active and reactive components of the impedance of these elements. The experimental results agree well with the theoretical results. [ABSTRACT FROM AUTHOR]

The realization of special types of the generalized-immittance converters will be given here using the second-generation current conveyor. Of particular interest in this paper is the new realization of the voltage generalized-immittance converter having conversion immittance function proportional to s. It will be seen that two realizations exist for each converter.
A special type of the current generalized-immittance converter was recently introduced, and used in one of the recent and most attractive RC active network synthesis procedures (Antoniou 1970). Antoniou (1970) used the operational amplifier as the active building block in the realization of the current generalized-immittance converter.
In a recent publication, Sedra and Smith (1970) introduced the second-generation current conveyor (will be abbreviated here as the current conveyor CC) and used it in the realization of some active network elements. The current conveyor is a versatile building block, as it can be used as a current summer, current differentiator, current integrator, current amplifier, etc.
In this paper the simulation of special types of both voltage and current generalized-immittance converters using the current conveyor will be given. [ABSTRACT FROM AUTHOR]

By inclusion of an external driving force, wave motion of any kind can be characterized by a dispersion function. This function is closely related to the energetic properties of wave motion, and then also to the averaged Lagrangian density. Linear and non-linear wave interaction can be analysed by inclusion of internal driving forces. Normalization procedures for the amplitudes can be avoided and time and space perturbations studied simultaneously. This analysis is further connected to slowly varying amplitudes and quasi-monochromatic waves. This paper presents the above-mentioned method and applies it to linear two-wave coupling, and non-linear three-wave coupling between positive and negative energy waves, and finally to amplitude modulation. The general equations obtained by this procedure are useful for general discussions. The simplicity of the method may prove useful in different applications.
The aim of this paper is to present a new and a simple method for analysis of wave interaction in dispersive media and to apply it on some illustrative problems. Further applications, which are found in plasma physics, microwave components and so on, will be presented later. [ABSTRACT FROM AUTHOR]

In this paper the gradual capture effect on the generation-recombination current in the space-charge region for an asymmetrical junction is studied. The theory is applied to the p-n InSb diodes. At forward bias, when the lifetime increases in the direction from p region to n region, the results we have obtained show that the current increases more rapidly with voltage than in the reverse case.
In this paper we shall take into account the gradual capture effect on the generation-recombination current in the space-charge region for an asymmetrical junction. [ABSTRACT FROM AUTHOR]

The well-known cyclotron resonance mechanism has been studied and energization of electrons in the magnetosphere has been explored. The relativistic variation of electron mass in the resonance process has been considered and the consequence of neglecting the relativistic electron mass variation has been discussed. At or near resonance the electron motion conforms with the motion of electrons in a potential well. Calculating the shape of the pseudo-potential for the magnetospheric plasma we have calculated the energy gained by the electrons. It is seen that 1 ev electron resonating with the electromagnetic wave (=10 rad sec and E=10 e.s.u.) acquires 1 Mev energy after 188 sec. The geophysical effect of the proposed energization is discussed.
It is well known that resonance of electrons with the electromagnetic waves propagating in the magnetoplasma energize the gyrating electrons. In our earlier paper (Nath and Singh 1970--hereafter referred as NS-I) we discussed the periodic energization of resonating electrons in the magnetosphere. In this paper we relax the requirement in Roberts and Buchsbaum's formulation (1964) and study the synchronous energization of the electrons in the magnetosphere. This is in accordance with the fact that high energy electrons have been detected in the magnetosphere and in the ionosphere. Davydovskii (1963) has suggested that under suitable conditions the charged particles could maintain synchronism with the electromagnetic waves and gain considerable amount of energy. [ABSTRACT FROM AUTHOR]

In this paper we consider how the electric potential varies in space and time during the formation of a plasma sheath. We give the variation of the wall potential in time, the potential profile at various stages of the sheath formation and the variation of the total current at the wall.
In this paper we extend the well-established static theory of plasma sheaths and discuss the growth of a sheath near a plane perfectly absorbing wall. Suppose that we introduce a plane perfectly absorbing sheet of material into a plasma which is electrically neutral and consists of electrons and a single type of singly ionized atoms. The mobile electrons will in general have a much higher velocity than the more massive ions and so initially more electrons than ions will strike the wall, and be absorbed, per unit time. Thus the wall will initially acquire a net negative charge. This charge will repel the electrons approaching the wall from the main body of the plasma and attract the ions. The net charge on the wall will continue to increase until the current density at the wall becomes zero. We wish to investigate the rate of growth of the potential of the wall and the profile of the electric potential at any time on the basis of a simple model. [ABSTRACT FROM AUTHOR]

This paper describes briefly the ideal characteristics required for tripping for faults within the first zone of a distance relay adapted to the protection of a transmission line. The quadrilateral characteristic on an R-X diagram, which is the ideal characteristic, is obtained using a new hybrid comparison technique. This technique possesses the flexibility of conforming to any desired characteristic by a simple change in the selection of current inputs. The relays are described in their block schematic form.
In this paper the first zone distance relay is considered and the desirable shapes of its characteristics are discussed. A new hybrid comparison technique is used to obtain these desirable characteristics. The comparator models are described in their block schematic form. [ABSTRACT FROM AUTHOR]

This paper attempts to analyze doubly terminated non-symmetrical lattices. The study is restricted to (a) rendering the lattice resistive and (b) the driving-point impedances at the ports to be capacitive and inductive.
In network synthesis the symmetric-lattice structure possesses a main advantage in that any symmetrical realizable two-terminal pair network can be realized as a lattice and, as such, requires only two parameters to characterize such a network. Though some work is done on non-symmetrical lattices (Advani and Reddy 1969, Lee 1963, Miyata 1963), the onus has been on symmetrical lattices.
Hopefully, this paper may lead on to some interesting applications, one such potential application appears to be in the lumped approximation of divergent and convergent exponential lines (Ramachandran 1962). [ABSTRACT FROM AUTHOR]

In a previous paper (Nandedkar and Bhagavat 1970) a quantum theory of finite d.c. resistivity of plasma was developed. In the present paper the effect of ion-molecule collisions on the noise emittance spectrum due to the electrons is considered. It is shown that the resultant noise power due to the electrons and the ions constituting the spectrum of electromagnetic radiations cancels out everywhere in the space.
In the present paper d.c. noise power generated by the plasma at thermal equilibrium, due to the electrons absorbing d.c. energy, in the presence of ion-molecule collisions is analysed. [ABSTRACT FROM AUTHOR]

Recent studies in non-equilibrium thermodynamics have led to the development of a new general transport theory. Applied to charged systems, this theory makes it possible to separate completely the effects of the processes of diffusion and drift and to calculate the amount of transport work necessary to support a current through each one of such processes, even in the presence of charge-carrier generation or recombination. Thus, considering forward conduction in p-n junctions and heterojunctions to be simply carried by the injection of minority carriers, several non-ohmic terms of transport work have been calculated of which three terms are particularly significant.
This paper explains forward conduction in metal-n Schottky diodes to be caused, like in p-n junctions and heterojunctions, by the injection of minority carriers into the n-type semiconductor. This carrier injection originates from an inversion (p-type) layer which is assumed to be between the metal and n-type semiconductor. Such an inversion layer has been recognized earlier by other workers. Theoretical results, derived by this author in previous papers for p-n junctions and heterojunctions, are found to be accurately in agreement with extensive experimental measurements conducted by several authors on: Au-Si, Pt-Si and Au-GaAs diodes at temperatures ranging from 42 to 433 degrees K. [ABSTRACT FROM AUTHOR]

The electron energy distribution has been calculated as a function of both position and time for an electron swarm travelling across a uniform electric field discharge gap. From these distributions, integral equations have been developed for the discharge parameters representing ionization drift velocity and diffusion and these lead to an alternative form for the drift and diffusion equation.
The magnitude of the discharge parameters have been calculated for electron swarms in molecular hydrogen for 10<E/pо<120 v cm-1 torr-1. A comparison with the values calculated from the usual form of the integrals for these discharge parameters, shows that although the mean energy and rate of ionization are the same, the drift velocity is larger and the diffusion coefficient now behaves as a tensor.
In part I of this paper (Lucas 1967), the spatial/time variation of the mean energies of swarm electrons have been calculated. The results have shown that the mean energies depend upon the longitudinal position within the swarm, with the electrons at the head of the swarm having a higher mean energy than the electrons in the tail. The electrons had to pass through a voltage large compared with their mean energy before the variation of mean energies throughout the swarm was less than 1%. It was concluded that this non-equilibrium state may be represented by adding extra terms to the Boltzmann equation, and that the integral expressions representing the discharge parameters would have to be redefined. All these modifications have been given in this paper, and to illustrate their magnitude, calculations have been made for electron swarms in molecular hydrogen. [ABSTRACT FROM AUTHOR]

In the present paper eigen-frequency of electronic damped oscillations in a plasma is derived. These oscillations are, however, not sustained. Further sustained electronic damped oscillations in the plasma in the presence of an external electric field are analysed.
Eigen-frequency of electronic damped oscillations in a plasma is derived in this paper. It is the intrinsic tendency of damped oscillations in the presence of local fields between charges of the plasma. These oscillations are, however, not sustained as such in practice. But if an electric field E be applied to the plasma model, sustained electronic damped oscillations result which are analysed here. [ABSTRACT FROM AUTHOR]

Theoretical investigation of random phase errors caused by surface irregularities in large reflector antennas has been the subject of many technical papers in recent years. This paper presents experimental results obtained by using a 4 ft diameter model whose reflector consists of an assembly of 54 triangular panels. Accurate control of artificial surface errors is achieved with the aid of micrometers attached to the corners of the panels. Thus the effect of random errors on the radiation characteristics of a large batch of nominally identical antennas can be successfully investigated. Good correlation between theoretical and experimental results has been obtained. The results also show that there is a significant advantage in using triangular panels to build antenna reflectors. [ABSTRACT FROM AUTHOR]

This paper describes the character of neuristor operation composed of a lumped parameter delay line with a negative resistance element parallel to the capacitance, as a function of the precise character of the negative resistance element. This model allows a neuristor pulse transmission in cases with very low characteristic impedance Z= (L/C). The experiments cover a Z value down to 11 . A lower characteristic impedance is possible. The model is analyzed applying Lienard's graphical method and linear approximations. As a result the criteria for characteristic parameters of negative resistance elements to operate as a neuristor are obtained. Based on the results, a neuristor with low inductance, small power, and high-speed operation can be designed. This circuit is convenient for neuristor logic, because, compared with the peculiar pulse width, it has a long delay time per section. The paper also describes neuristor logic without, an R-type junction, using only the threshold property of the neuristor. A conventional Crane's R-junction is also presented. For this neuristor model a destructive collision phenomenon exists independent of the refractory period phenomena. The mechanisms of these phenomena are clarified. [ABSTRACT FROM AUTHOR]

The expressions previously derived by the author for the resistance parameters of the composite transistors are used to investigate theoretically the open circuit characteristics of the compound configuration consisting of two-point contact type transistors. It is found that the system has, in general, a much smaller current gain, voltage gain, input resistance and higher output resistance. The characteristics are greatly modified when the second-point contact type transistor is replaced by a junction type.
Recently the author, in his paper (Singh 1969), has derived the general expressions for the resistance parameters of the composite transistors in terms of the open circuit parameters of the individual transistor. The characteristics of the compound systems in all the three configurations were, however, not theoretically investigated although these have already been discussed by Suen (1968) in terms of the hybrid parameters. Therefore in this paper the author presents the quantitative analysis of the characteristics of the Darlington configuration on the basis of its resistance parameters. [ABSTRACT FROM AUTHOR]

In this paper it is shown that any arbitrary driving point function can always be realized as a two-port active network having prescribed transmission zeros in any one direction and terminated by a pre-fixed passive RC admittance.
In the synthesis of arbitrary driving point functions, one of the methods adopted is to realize it as a two-port network terminated in an RC impedance Z. This load impedance Z is fixed by the type of polynomial (Horowitz 1959, Thomas 1961) or rational function (Mitra 1962) decomposition used. Also this Z may be positive (Ramachandran and Swamy 1967) or negative (Kinariwala 1959). Recently, the driving point impedance synthesis was extended to cover the case of an arbitrary pre-fixed RC load impedance (Narasimhan and Ramachandran 1968). In all the above methods, the forward and backward zeros of transmission are fixed and are obtained only by the type of decomposition used. [ABSTRACT FROM AUTHOR]

Complementary (maximum and minimum) variational principles are used to obtain upper and lower bounds for capacities in microwave filter problems. The results are illustrated by calculations for a periodic system of cylindrical rods between two parallel ground planes.
In this paper we shall study the boundary value problems which arise when a periodic system of cylindrical rods lies between two parallel ground planes. Such systems are used in certain microwave filters.
The basic problem is to determine the capacitance of the system when either the odd or even mode is excited. The odd mode gives rise to a Dirichlet problem and the even mode gives rise to a mixed boundary value problem. Approximate solutions for the fields in these eases have been obtained by Richmond (1923) using a conformal transformation method, by Chisholm (1956) using a stationary (variational) principle, and by Cristal (1964) using a numerical method for the appropriate integral equation. An alternative approach to the problem is pointed out in this paper. It is based on the theory of maximum-minimum (complementary) variational principles, and leads to both upper and lower bounds for the capacitance. [ABSTRACT FROM AUTHOR]

When a radiating source is immersed in an isotropic compressive plasma, a longitudinal electroacoustic wave may be excited in addition to the usual electromagnetic wave. These waves produced by linear antennas have been studied by the author in a series of papers. The present paper, called part VI of the series, deals with some features of the electric field associated with electroacoustic waves excited by linear antennas. It is shown that the distribution of the field is oscillatory with broadside symmetry and that the maximum occurs almost in the broadside direction.
The investigations presented in the current paper indicate the electric field of electroacoustic waves to be oscillatory having a maximum almost in a broadside direction. About this direction, as expected for the RCFLA, the P mode electric field pattern is symmetrical. But even for the NREFLA there is some symmetry about the broadside direction which improves further with larger values of (c/v)> 10. Thus the P mode field pattern is symmetrical for both types of linear antennas and so differs from the EM mode field pattern which is know to be symmetrical for the RCFLA and non-symmetrical for the NREFLA.
In the end it may be concluded that for frequencies confined to the first Fraunhofer zone, the assumed sinusoidal current distribution with as the propagation constant forms a workable and reasonably simple model to describe the main salient features of linear antenna performance in a hot plasma. [ABSTRACT FROM AUTHOR]

The paper describes a second-order non-linear system generating discontinuous oscillations. The system comprises a linear amplifier, a clipper and an L-C network connected in cascade and joined by an overall regenerative feedback loop. The mechanism of oscillation is analyzed and the expression for its time period is obtained. The same method of analysis is also extended to systems comprising more complicated L-C networks. The above circuits generate square wave voltages of constant amplitudes and frequencies variable over a wide range. [ABSTRACT FROM AUTHOR]

The efficiency with which a complex electrical network may be analyzed by a digital computer using topological formulas depends largely upon the efficiency with which the trees and directed trees of the corresponding graph are generated. The problem of efficient generation of trees of a graph has been treated rather extensively in the literature. In this paper it is shown that many of the existing techniques in the literature, seemingly so different in their appearance, are actually the variants of the Wang algebra formulation. Thus, they can all be unified. The unified theory enables one to summarize many of these results systematically and to provide a simple and easy way for their derivations.
In the paper we have shown that many of the existing results described in the literature on the problem of generation of trees of a graph, seemingly so different in their appearance, are actually variants of the Wang algebra formulation. Thus, it enables one to provide a unified theory for their derivation and to summarize most of these results systematically.
The main advantage of the Wang algebra formulation lies in the fact that once a desired set of sets, which can be obtained easily by inspection, is derived from a given graph all the remaining manipulations are algebraic. It is not necessary for one to go back to the original graph to see whether a generated term forms a tree (co-tree) or not. However, the techniques are not very efficient for large graphs because duplicated terms are generated during the process. Apart from slowing down the process of generating trees, this limits the sizes of the graphs that can be analyzed since one must retain the set of all trees in computer memory and check each new tree against the list for possible duplication.
The application of the Wang algebra technique to the generation of directed trees and multi-trees has been considered by Chen (1966). A special case of which is recently given by Shinoda (1968). [ABSTRACT FROM AUTHOR]

Synthesis of multi-port networks is attracting increasing attention in network theory. On the other hand comparatively little work has Been reported on active RC multi-port transfer function synthesis. This paper presents an elegant synthesis procedure to realize any arbitrary rational m n open-circuit voltage-transfer function matrix where m and n are, respectively, the numbers of the input and output ports. The realization results in a grounded network requiring (2m+1)n RC one-ports and (m+1)n grounded operational amplifiers and hence is attractive from the practical point of view.
The present paper discusses the realization of an arbitrary rational m n open-circuit voltage-transfer matrix where m is the number of inputs and n is the number of outputs. This type of network is of practical importance in systems where simultaneously more than one input and output are required. [ABSTRACT FROM AUTHOR]

This paper describes an investigation into the electrical behaviour of shallow implantations of boron and phosphorus in silicon. The clover-leaf Van der Pauw patterns were defined by planar masking techniques, and were ion implanted to produce a 'tailored' impurity profile of approximately uniform concentration with depth.
It was found that phosphorus implantations became fully electrically active after annealing at a temperature between 620degreesc and 750degreesc, whereas the boron implantations required an anneal in excess of 900degreesc. A subsidiary activity peak, whose magnitude increased with the ion dose, was observed for the boron implantations after annealing at a temperature around 520degreesc.
The principles of ion implantation have been discussed at length by other authors, for example Gibbons (1968), Kleinfelder (1967) and Nielsen (1967), and recently Large (1969) has described the techniques used at S.E.R.L. During the past two years, papers have been published showing the electrical properties of silicon implanted with various ion species, but very little information has appeared on the electrical behaviour of shallow implantations of boron and phosphorus. The present work was initiated to measure these properties in order that the electrical behaviour of ion-implanted silicon devices be more fully understood. [ABSTRACT FROM AUTHOR]

The acquisition behaviour of the frequency of an input signal by means of phase-lock loops is investigated. Sufficient conditions for acquisition are obtained by means of Lyapunov's direct method. A systematic procedure is developed for the computation of Lyapunov functions and acquisition regions. It is illustrated by two examples. Finally the power and the limitations of this approach are discussed.
In this paper a systematic procedure is proposed for the selection of a state vector representation of a phase-lock loop with an arbitrary filter, for the construction of suitable Lyapunov functions, and for the computation of stability regions of the equilibrium states. The proposed technique is then applied to an example which was also considered by Holtzman and Rue (1964). The plot of the results clearly shows that a considerable improvement of the stability region is obtained. Finally the power and the limitations of the approach are discussed. [ABSTRACT FROM AUTHOR]

This paper considers the sensitivity of the power gain of a tuned conjugate-matched amplifier to changes in active device parameters, for the general case wherein the active device may be embedded prior to termination. Prediction of the effect of simultaneous spreads in the eight parameters of the active device is based upon a simple expression--here also displayed as a three-dimensional model for ease of insight--relating conjugate-matched gain to two device parameters. These parameters are representative of device activity and non-reciprocity, and are separately invariant to common types of embedding. A new basis is proposed for the characterization of spread between two devices, each represented by a point in a three-dimensional space, and leads to a simple description of the effect of device spread upon power gain. The effect on gain spread of common types of device embedding is discussed and its simple description verified experimentally. A prerequisite to the treatment of batch spread is the realization of an 'average device', and is effected by standard statistical techniques. For the minimization of gain spread in amplifiers affected by batch spread in active device parameters, a heuristic design strategy for the best choice of device embedding is proposed.
This paper is concerned with the above problem as it arises with an active two-port network designed to exhibit useful power gain at a single frequency. It is, therefore, particularly pertinent to the design of narrow band amplifiers. Indeed, the illustrative numerical examples refer to a transistor tuned amplifier, although the underlying theory is valid for any three-terminal active device. It is the object of the paper to consider how an active device might best be connected between source and load terminations--but using an intervening embedding network if necessary--in order to realize a useful power gain while minimizing its spread. [ABSTRACT FROM AUTHOR]