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The document is comprised of a portion of workbook intended for use in an engineering laboratory course on analog computers. The portion included deals with model electronic machines and methods of their application, with special reference with the Mn-7 and IPT-5 computers., Edited machine trans. of mono. Vychislitelnye Mashiny Nepreryvnogo Deistviya. Laboratornye Raboty po Kursu, Moscow, 1965 p246-85, 211-2.

To determine the most suitable technique to provide a wideband (30-mc) high level (150 volts, peak-to-peak) video amplifier for use with experimental and developmental television projectors, various techniques for obtaining wideband amplification were investigated. The techniques investigated were: shunt, series and combination peaking, distributed amplification, negative feedback, and modulated radio frequency carrier. The primary problem was that of providing wideband amplification and high output level to a load that consisted of a resistor in parallel with various unavoidable capacitances which result from state output capacitance, stray and wiring capacitances, and the input capacitance of the driven device. The capacitance limits the bandwidth of the amplifier, inversely proportional to the resistor-capacitance product. The study resulted in the design and construction of a solid-state video amplifier, employing a combination of feedback and peaking techniques, which meets the required performance characteristics. The amplifier provides a bandwidth of 30 Hz, a gain of 300 and an output capability of 150 volts. (Author)

General conclusions drawn concerning the effect of feedback on a common emitter amplifier are: Series feedback (1) Increases the low frequency input and output impedances of the transistor itself. (2) Decreases the voltage gain, current gain, and gain-bandwidth product of the amplifier. (3) Increases the upper cutoff frequency of the amplifier. (4) Decreases the sensitivity of the amplifier to changes in the transistor parameters; Shunt feedback (1) Decreases the low frequency input and output impedances of the transistor itself. (2) Decreases the voltage gain, current gain, and gain-bandwidth product of the amplifier. (3) Increases the upper cutoff frequency of the amplifier. (4) Decreases the sensitivity of the amplifier to changes in the transistor parameters. (Author)

An analysis of the breakpoint conditions necessary to form a constant bandwidth, tuned radio frequency, piecewise logarithmic amplifier is presented. The amplifier uses DC feedback rather than saturation or bias control techniques and the logarithmic transfer function is essentially independent of temperature and transistor parameters. The suitability of the device for pulse operation is considered, along with the effects of low frequency and high frequency modulation, and of operation at frequencies other than resonance. (Author)

For many military applications, low frequency oscillators (approx 100 Hz) are required which maintain their frequency within 5 parts in 10,000 after they have been exposed to an acceleration of 30,000 g for 100 ms, and also after a storage period of 5 yr. In addition, the same stability must exist over the total military temperature range while a constant acceleration of, say, 5000 g in any direction is applied for about 200 sec. The characteristics of mechanical systems and various electrical circuits proposed for the time bases will be summarized. It will be shown that oscillators, based on the use of RC networks and solidstate negative feedback amplifiers, can fulfill the requirements. It will also be shown that, for cost reduction, the conventional amplitude control over many cycles can be replaced by an instantaneous limiter without detrimental effects on stability. (Author)

A brief description is given of a thermoanemometer which measures the mean velocity of air flow (up to 120 m/sec) and velocity pulsation intensity up to 10,000 c,. Compensation of thermal inertia of the filament is realized with the aid of a feedback amplifier, which makes a corresponding current regulation of filament heating current and automatically maintains the resistance of this filament. The instrument has a special amplifier, rectifying the non-linear dependence of the signal upon the rate of flow coming from the filament. Measurement of mean square root values of velocity pulsation is made with the aid of a pulsation amplifier, vacuum thermocouple, and thermo EMF amplifier., Unedited rough draft trans. of Politekhnicheskii Institut, Leningrad. Trudy (USSR) n217 p176-9 1961.

Given the time domain specification for any (or any two) of the networks--the source network, the matching network, and the load network--specify the remaining network(S) so that the maximum total energy is transferred from the source to the load for arbitrary source voltages. This problem can be solved (i.e., the matching network can be specified, its realizability being an open question) in general by means of the classical calculus of veriations, which yields time domain specifications for the unknown network and simple conditions which show the limitations on the applicability of the results. The further question of when the specified matching networks can actually be realized (or to what extent they can be approximated) is included. (Author)

An experimental program was conducted for the prupose of investigating a particular cross correlation signal processing technique, (Spectrum Compression) and to define characteristics of interest in potential applications to Army weapons systems. No significant discrepancies were found to exist between theory and the experimental results. The Spectrum Compression, cross-correlation technique possesses unique characteristics which makes it particularly suitable to applications in radar, secure communications, command guidance links and other weapon systems functions. The appendix presents a simplified method of calculating Fourier transforms of waveforms applicable to this cross-correlation technique. (Author)

Contents: Association of invariance theory with the theory of differential regulators The possibility of compensation and recompensa tion of other (excluding static) error com ponents in differential systems Comparison of rigidity and stability of differ ential stabilization systems The possibility of compensating the effects of nonlinearities in various components of dif ferential systems Utilization of a differential system for the elimination of the insensitive zone in a magnetic reversing gear The equivalence condition of systems of differ ential equations and disturbance control systems Designing automatic systems stable with respect to disturbances Determination of the form for the transfer functions of components added to a system to achieve invariance Determination of corrective element parameters Evaluation of different methods for introducing corrective elements into the system Determination of the effect of low-value correc tive element parameters on process stability and quality in stabilization systems

A description is given of the development and performance of instrumentation for the continuous measurement of solar and sky ultraviolet radiation as received on a horizontal surface from sun and sky (pyranometer) as well as in normal incidence from the sun (pyrheliometer). Sources of errors such as change in air mass (filter-weighting factor) and environment (transient response) are discussed, and areas of needed improvement are indicated. (Author)

A description is given of design and operational principles of electrical analog devices and the follow-up systems used in conjunction with them. Attention is devoted to the physical essence of the processes that take place in the computers, with the object of assisting officers, noncommissioned officers and soldiers to acquire skill in wor ing with computers and instru ents in which they are employed, an to service them properly. (Author)

The feasibility of a rocket observational system employed for target surveillance or cloud-cover observation is explored, as well as the use of an experimental rocket for this purpose. The component parts of the airborne instrumentation are examined from the viewpoint of their application to this task. Temperature and insulation requirements are also investigated. The adaptation of existing meteorological equipment for receiving surveillance information is discussed. It is concluded that this surveillance technique is technically feasible, but would require an integrated rocket and payload development to be operationally useful. (Author)

A variety of two-core full-wave self-saturating magnetic amplifiers in conjunction with either frequency dependent loads or feedbacks are studied, emphasizing the bridge-type amplifier with resistive-capacitive load and conventional feedbacks and the same amplifier with resistive load and frequency sensitive feedback networks. Steady-state gain expressions are derived for square-wave and sinusoidal gate supply voltages. The possible subharmonic response of the amplifier with resistive - capacitive load is explained and conditions for its avoidance are derived. The transient behavior and stability of the various second-order circuits has been studied using a difference-equation approach, and the results are interpreted in terms of an equivalent modular differential equation of the second-order. Extensions to sinusoidal supply are considered and the limitations of the squarewave analysis for such situations are discussed. Extensive checks of overall system behavior confirm the validity of the analyses. (Author)

The optical portion of a device for delivering high energy densities of optical frequency electromagnetic radiation to a point in space is discussed. The energy is assumed generated in an active laser material. The problems of extracting this energy coherently and focusing it are considered. Limitations due to optical material considerations and fabrication restraints are investigated. (Author)

Results are given of a development effort to design a transistorized servo amplifier for general use in a variety of commonly occurring servo systems using BuWeps precision components. Detailed information applicable to Amplifier AM-2937(XAN-1) USW is presented. Servo applications and techniques for the servo systems designer are reported. (Author)

A wide-band, solid-state, hard limiter with unusual dynamic capability is described. The method of limiting employed is a nonlinear process in the form of diode feedback circuits in conjunction with high-gain linear transistor amplifiers. Problems encountered in the design of a limiter are nonlinear, but techniques are derived that enable the engineer to estimate the limiter performance without resorting to computer solutions. Limiters of the form described have obvious application in systems that require elimination of amplitude information. (Author)

A method is described of obtaining very accurate, linear, CRT (cathode-ray-tube) sweeps. Sweep accuracies approximately 100 times better than those obtainable by conventional techniques are possible. The technique is best applied to unmodulated CRT sweeps; however, it may also be applied to amplitude-modulated sweeps and, under special conditions, to intensity-modulated sweeps. A feedback control loop is used. A linear second-order model system is developed and analyzed, in generalized terms, for three simple input-error functions: a step, a ramp, and a sinusoid. From these results an idealdesign approach is developed, and the limitations of this approach are indicated. Other design approaches are discussed briefly. Some special design considerations are discussed and other possible applications of the technique are mentioned. A sample calculation of the major parameters of a specific system is included as well as some experimental data and results obtained from a crude breadboard model. The experimental results confirm the feasibility of the technique. It may find application in video mappers, radar display systems, and other display, recording, or scanning systems requiring extremely accurate CRT sweeps. (Author)

Contents Back-scattering from cones Scattering from multiple targets Scattering from materials with gyrotropic media Radiation from a modulated ferrite traveling-wave antenna Ferrite field-displacement device for slot-coupling control Diffraction studies Nonlinear semiconductor device circuitry Network theory Electronic circuits research Antenna arrays from a data processing viewpoint Information theory Research in high-temperature semiconductor devices

Contents: Scattering from a prolate spheroid; Diffraction by cylindrical reflectors; Large slots in rectangular waveguide; Multidimensional arrays; Gerrites in broadband microwave systems; Scattering by a ferrite obstacle in a multimode waveguide; Radiation pattern from a ferrite-terminated rectangular TE10 waveguide; Broadband transmission in waveguides; Microwave cavity filters using degenerate modes; Microwave radiometry; Near-zone fields of paraboloid reflectors; Transistor feedback amplifier design; Broadband matching of arbitrary impedances; Transistor circuit research; Nonlinear predictor stabilization; Magnetic recording of digital data. (See also AD-074 692)

Covers a study on a simulation of a 50-horsepower high-speed induction motor on an analog computer. The investigations described in the report are intended to accomplish several purposes. One purpose is to develop in more detail the simulation equations from the dynamic equations provided on induction motors in recent machinery textbooks. A second purpose is to illustrate the determination of per-unit and amplitude scaled equations, and the calculation of potentiometer and amplifier gains. Another purpose is to record in detail the induction motor variables simulated for assistance and comparison in performing future work in this area of simulation. The results of this induction motor simulation provide a base from which to approach more complex control and application simulations which contain the induction motor as a component such as proposed electrical propulsion systems for various land vehicles. (Author)

Special circuitry for gating and deflecting the IMCO tube has been developed. It includes high-level d.c. feedback amplifiers for deflection (1200 volts c.t.), gating-pulse generators (up to 1000-volt pulse), and associated circuitry. Images can be shifted and then superimposed to test for coincidence and registry. This can be done on fixed and moving objects. Typical circuit features are described. Progress in tube construction and fixturing also is presented. (Author)

The relation between input and output of many linear systems and circuits is ordinarily found by repeated use of functional inversion, i.e., the process where, given y = Zx one finds x = (1/Z)y. Many nonlinear circuits and systems can be analyzed using functional inversion in exactly the same way. The methods for accomplishing this inversion however are different. Where the nonlinear relations are given as graphs, the inverse relations are shown by the same graphs. Where derivatives and integrals are involved, approximate inverses can be obtained using a generalization of the 'reversion' method of Sims and Pipes, or the iteration method. Practical examples given include the design of a nonlinear equalizer and the analysis of a feedback circuit, a tunnel diode network, and an automatic gain control circuit. The mathematical bases of the methods are discussed, along with their representation by flow graphs, and the insertion of initial conditions. (Author), Pub. in IEEE Transactions of the Professional Technical Group on Circuit Theory vCT10 n2 p168-80 Jun 1963 (Copies not available to DDC or Clearinghouse customers). Revision of manuscript submitted 28 Jun 62.

An investigation is described of new techniques for the stabilization of the gain of parametric amplifiers used in the front end of radiometer receivers. A summary of the basic theory of parametric amplifiers is given with emphasis on the degenerate mode of operation as applied to receiver front ends for microwave radiometry. The development of a 15.5 gc amplifier is described. This amplifier utilizes gain stability by feedback of a reference noise level to control the pump power. The amplifier has 17 db gain, 70 Mc bandwidth, and 3.0 db noise figure. The utilization of feedback results in a 15 to 1 improvement of gain stability for pump power changes. A 1.0 gc degenerate mode amplifier for use as the first stage of a radiometer i-f amplifier is developed. A feasibility study of a degenerate mode Ka-band parametric amplifier is described. (Author)

Communication between an airborne navigational computer and the navigator requires means for encoding decimally entered information, displaying output information, and converting between the binary notation of the computer and the decimal notation of the operator. A design is presented of a device which performs those functions. Conversion between binary and B.C.D. notation is accomplished by a fixed-program, special-purpose computer coupled to the navigational computer. Display devices for decimal digits are proposed based upon a small stepping motor with opto-electronic feedback to assure that the device is actually in the position called for. A complete logic design is presented. Suggested construction is of micro-miniature electronic blocks available now or in the near future. (Author)

An analysis of the noise and response characteristics of an atmospheric temperature measuring system manufactured by National Electrolab Associated Limited was conducted. (Author)

The report presents several video and pulse circuits designed during the past 5 years (1963 through 1968). These circuits include video amplifiers, variable gain amplifiers, logarithmic amplifiers and switching circuits. Basic analysis of each circuit is presented as well as examples. (Author)

A study was conducted at the Nuclear Aerospace Research Facility (NARF) to develop improved electronics for nuclear radiation detectors used in space vehicles. This study was performed concurrently with and is closely related to another NARF program involving the design and construction of an electron-proton spectrometer for use on USAF satellites. To illustrate the problems associated with integration of many separate circuits into a functioning system, the various circuits that were the subject of the electronics study are discussed in relation to their use in the electron-proton spectrometer. The circuits discussed include: (1) charge-sensitive amplifiers for use with semiconductor nuclear-radiation detectors, (2) pulse-amplitude discriminators, (3) control circuits, (4) power supplies, and (5) Logarithmic count-rate meters. The temperature stability and low power consumption of these circuits are of particular significance. (Author)

Theoretical analyses are carried out for transistor integrators and differentiators of the single-stage, negative-feedback amplifier type, assuming linear circuit theory and the applicability of the low-frequency transistor equivalent circuit. Comparisons are made between the theoretical results thus obtained and measured behavior of actual circuits. In all cases, excellent agreement is obtained. A practical single-stage circuit has been designed for the integration of 50 volt pulses, 10 microsecs in width. The output waveform is linear within 3%. A second practical circuit allows accurate integration of 1000 cps sine and square waves. In addition, a single-stage transistor circuit has been designed which allows the accurate differentiation of sinusoidal and triangular wave input voltages. (Author)

This proposal describes an analog to digital converter suitable for use in small earth orbiting satellites. The theory of operation is also discussed. Some of the advantages of this converter are that (a) for the most part it can be constructed from available integrated circuits, (b) it is small in size and consumes less power than A/D converters of other types, and (c) the design requires no parts with light tolerances and is free from errors due to drift. It is proposed that this analog to digital converter be used in the X-Ray Explorer Satellite and in the Navy Navigation Satellite programs. (Author)

Presented in this paper are the results of a particle-in-cell modelling of a novel high-power microwave (HPM) source which combines the properties of two devices. The first prototype is a magnetically insulated transmission line oscillator (MILO), an HPM self-oscillator which does not need an external magnetic field and irradiates a narrow spectrum depending on its iris-loaded slow-wave structure. The second prototype is a plasma maser, a Cherenkov HPM amplifier driven by a high-current relativistic electron beam propagating in a strong external magnetic field in plasma which acts as a slow-wave structure. The radiation frequency of plasma masers mainly depends on an easily variable plasma concentration; hence, their spectrum may overlap a few octaves. The plasma-based HPM device described in this paper operates without an external magnetic field: it looks like an MILO in which the iris-loaded slow-wave structure is substituted by a hollow plasma tube. The small pulse duration of ∼1.5 ns prevents a feedback rise in the 20-cm long generation section so that the device operates as a noise amplifier. Unlike conventional ultra wideband generators, the spectrum depends not only on the pulse duration but mainly on plasma, so the operation frequency of the device ranges within 12 GHz. For irradiated frequencies above 2 GHz, the total pulse energy efficiency of 7% is demonstrated at the HPM power level ∼1 GW. © 2018 Author(s).