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A series of experiments was performed to develop the procedures and techniques that are required to operate the Gamble I facility so that reproducible, fairly uniform electron beams could be obtained. With one guide cone, two entrance apertures for the guide cone, and five different charging conditions, six fluence levels were established (20, 40, 60, 100, 160 and 200 cal/cm squared).

A feasibility study was conducted on the design and fabrication of a thin-film precision ratiometer developed for use in the electronic timer of the XM732 Short Intrusion Proximity Fuze. The ratiometer network consists of a 432-kohm linear variable resistor and a 3-kohm fixed resistor that provides a means of setting a delay time of 2 to 144 sec before fuze turnon. Nichrome and gold were vacuum deposited onto a glazed ceramic substrate with the resistor-conductor pattern being selectively etched. This approach utilizes a step-like conductor/commutator design that permits settability within 0.5 sec through a movable spring contact. Resistor tolerances of plus or minus 20 percent with a linearity of plus or minus 1.5 ratio units through an angle of 324 deg were demonstrated.

Thermal focusing contributes to laser beam divergence which is a problem in the design of laser target designators. Measurements of the thermal focusing induced in a neodymium:yttrium aluminum garnet laser rod by input powers typical of target designators are described. The application of such measurements in the design of laser resonant cavities is illustrated.

An instrumentation system is described that enables a jet aircraft to maintain a linear high-angle dive path at constant speed. The density and motion of the air, as well as the mass, thrust, and drag configuration of the aircraft affect the performance of an aircraft diving toward a fixed point on the ground. Standard airborne instrumentation is insufficient to maintain a plus or minus one deg course and a plus or minus ten percent ground speed in a 30-deg dive. It was demonstrated in a series of test dives at various fixed angles that, by using ground based instrumentation, how these precisions could be attained over portions of the dive.

An investigation has been made of the quartet I ground term of Nd(3+) in YVO4. Wavelength and polarization measurements of the absorption in the wavelength range from 0.8 to 2.6 micrometers were used to establish energy levels for the quartet F(3/2), quartet I(9/2), quartet I(13/2), and quartet I(15/2) multiplets. These data were correlated with reported spectra in the literature, and an energy level scheme was obtained that identifies 25 out of the 26 ground term levels. Theoretical (g(parallel) and g(perpendicular) values) are in good agreement with Ranon's reported values for the ground state; thus, the ground state symmetry property was determined to be Gamma (7,8) in S(4) notation or Gamma (7) in D(2a).

The performance of a backscatter nephelometer in the mapping of aerosol attenuation and backscatter coefficients is evaluated. This instrument, coupled with an automated data processing technique described, performs quite satisfactorily and provides an excellent means of cloud data gathering and optical fuze test support. In addition, some parameter profiles of fair weather cumulus clouds observed in flight tests are presented.

One hundred flueric triggers and their coverplates were cast in epoxy; the coverplates, which included integral tubing connectors, were glued to the triggers. These logic elements were then tested and the test results interpreted to judge the usefullness of the manufacturing technique for the small scale production of flueric logic elements. The tests measured output pressures and control switching pressures for various loading conditions. Large deviations exist between like measurements for different elements in the test group. Tests of elements that were bolted rather than glued indicate that the method of fastening the coverplate to the trigger caused some, but not all, of the deviation. The results of these tests show that the cast epoxy manufacturing process used for these triggers is not entirely satisfactory. (Author)

The single-component Landau-Ginzburg problem is solved approximately in one dimension. A variational solution is obtained for the equivalent anharmonic oscillator problem in quantum mechanics; the specific heat, the susceptibility, the order parameter correlation function, and the order parameter in a small external field are obtained from the solution. These results show that there is no sharp phase transition, although the system becomes ordered at low temperatures upon application of a very small field. (Author)

Several extremely lightweight prototype electromagnetic horns with low side lobes were designed and fabricated. Those lightweight horns are made by copperplating on low-density, low-loss dielectric foam substrates of a given shape and size. Corrugated walls are incorporated in the E-plane of the horn to eliminate scattering at the edges, thus substantially reducing side lobes and back radiation. Design techniques and dielectric material characteristics are discussed, and performance data of models designed for different frequency bands are illustrated. Results show that these design techniques realize as much as 10 to 1 reductions in weight in comparison with the conventional thick-walled horns. Moreover, the copperplated dielectric-foam horns are efficient, highly directional with good radiation pattern characteristics, and can be made to operate over a reasonably broad bandwidth. (Author)

The effects of neutron and gamma irradiation on high-power (>200 mW) GaAs dome infrared emitters are reported. The threshold radiation levels for degradation of radiated power output, power efficiency, and external quantum efficiency are observed for neutron fluences of 1 x 10 to the 12th power n/sq. cm. (E > 10 keV) and for total gamma doses of 1 million rads (Si). These parameters decrease by three orders of magnitude at 2.2 x 10 to the 14th power n/sq. cm. for the neutron-irradiated device, and at 10 to the 8th power rads (Si) for the gamma-irradiated device. The reduction in power efficiency and external quantum efficiency with irradiation can be explained by the reduction in total minority carrier lifetime. The effect of radiation on the dome is negligible. The results of intensity-voltage and current-voltage measurements confirm that, even under the effects of nuclear irradiation, light is emitted in the diffusion region of the junction and that the charge flow is a diffusion process. (Author)

Attempts are made to reassign symmetries to the (sup 3)H(sub 6) and (sup 3)H(sub 5) levels of Tm(3+):YVO4 reported by Knoll in order to obtain a better fit between theory and experiment. Based essentially on Knoll's assignments, Wortman, Leavitt and Morrison have made an elaborate analysis of the full f12 configuration, but could obtain a fit to only 14/cm. The present analysis does not improve on the results of Wortman et al, indicating that further experimental data are needed. (Author)

An investigation has been made of problems that would be encountered in providing for and using the nuclear power from the beta decay of Tm170 to pump a rare-earth ion laser. The Tm170 is to be created by bombarding LiTmF4 containing stable Tm169 by thermal neutrons. The rare earth impurity ion selected for the laser will substitute for a small amount of the thulium. It was found that exposing the LiTmF4 crystal to a thermal neutron flux of 10 to the 14th power/sq cm-sec for 3 days could create a power density within LiTmF4 comparable with that of a 100-W xenon lamp used for optically pumping Ho(3+). The energy level of escaping radiation is low enough so that shielding to insure safe handling without compromising portability can be provided with no great difficulty. Range calculations showed, for example, that the range of 1-MeV electrons in liquid nitrogen is only about 0.5 cm. Low-Z material can be used for shielding the beta rays because of the lower intensity bremsstrahlung that would be created thereby. (Modified author abstract), See also AD-775 424.

A fundamental limitation in microwave measurement of plasma parameters is established: It is shown that it is not possible to determine experimentally such plasma parameters as electron temperature, electron density, or collision frequency by means of a microwave system operating at a frequency well below the plasma frequency because the plasma boundary layer exerts a prominent effect on the measurements. A numerical example is given, using published results for argon. (Author)

The expression of certain infinite power series as contour integrals is shown to lead to analytic continuations of the power series. Problems associated with this procedure are discussed; particular emphasis is given to the problem of sorting out extraneous poles introduced by the procedure. (Author)

An equation is derived that may be used in conjunction with experimental power measurements to determine the temperature at which a thin-film resistor is burned out. The objective of the analysis is to provide information that may be used to assist in the design of an inexpensive, match-like detonator activated by the heat generated in a thin-film resistor pulsed by a capacitor discharge system. (Author)

A mathematical design for an adaptable IRIG standard commutator based on a ring counter is presented. Operation of a prototype is explained, and complete specifications are included. (Author)

The report describes the Army Emergency Respirator, a small pressure-cycled respirator that uses a fluid amplifier as its basic component. The calibration technique applied to achieve the desired functional operation is presented. To determine performance capability of the respirator, engineering tests were performed using tanks to simulate lung compliances and perforated disk to simulate airway resistance. From these tests, the switching pressures, cycling rates, tidal and minute volumes, and gas consumption of the respirator are defined quantitatively for given load condition. The engineering tests, along with some earlier medical tests, suggest that the respirator can provide adequate ventilation. (Author)

Shock-tube test times taking into account the boundary layer growth in argon are calculated for a variety of tube diameters and initial gas pressures. In addition, the processes involved in establishing flow in a supersonic shock tunnel are discussed. The results of two calculation procedures for determining the starting time in a shock tunnel are compared for a specific example. (Author)

An active all-pass network that has two real axis poles and mirror image zeroes is analyzed and a means of realizing even-order 90-degree phase difference networks with this circuit is demonstrated. A step-by-step design procedure and the schematic of an 8th-order network constructed thereby are presented. (Author)

This is the first report describing HDL development on a ceramic peizoelectric memory. The device is in the form of a disc, 1 in. in diameter and 0.025 in. in thickness containing silver electrodes so placed that it operates as a piezoelectric motor-generator at its resonant frequency. Two stable states, permitting binary coding of information, are realized by utilizing the differing outputs resulting from the presence or absence of remnant polarization between the generator electrodes. It was concluded from voltage time experiments that a write-in voltage of about 1500 V dc applied for 3 sec will induce the 'one' condition (ca. 10 V peak-to-peak) and a subsequent write-in voltage of 1500 V dc of reverse polarity for 3 sec will induce the 'zero' condition (ca. 2-3 V peak-to-peak). The device retains the stored information after a period of time in the 'no-power' condition and the readout is non-destructive. The device has isolated read and write electrodes and requires no internal mechanical switching in its connection to the timer circuits for which it will serve as a memory. (Author)

A symmetrical-triangular-waveform generator has been developed. The output frequency of PRF is voltage controlled. Five discrete PRF's spanning a ten-to-one frequency range are provided. The amplitude of the output waveform is adjustable from 20 to 60 v peak-topeak. The circuit operates within specifications over a temperature range of -65 to +165F. (Author)

The Harry Diamond Laboratories Hot-Core Wind Tunnel is an aerothermal test facility designed for use as a flight environment simulator for high-speed projectile fuzes, and as a research tool for the development of more reliable and economical fuze systems. A physical description of the facility is presented, its perormance capabilities defined, and its simulation potential established. (Author)

During periods of inadequate human respiration, artificial ventilation can satisfactorily assume the function of the patient's breathing mechanisms in most situations. Such ventilation can be administered by mouth to mouth techniques, manual methods, or automatic devices. The purpose of this report is to discuss the physiological parameters governing the design of automatic respirators and to review the design of those currently in use. (Author)

An experiment was performed to verify the authors' new concept that a two-section transformer may be designed in which the length of each section is less than a quarter wave length and may be treated as an independent variable. A two-section J-band waveguide transformer, having an arbitrarily chosen total length of one-fifth of a guide wavelength, was designed to match a 4:1 impedance mismatch at 5500 Mc. The design procedure is described in detail, including corrections for capacitive reactances introduced by each step discontinuity in the waveguide. The experimental results are in excellent argeement with the design objective. (Author)

A solid-state, low-voltage regulator accurate to 0.1 percent with temperature stability has been developed. Employing thermistor compensation, forward-biased diodes, and matched silicon transistors, it represents a significant advance in the state-of-the-art. The circuit discussed herein yields 1.500 = 0.001 v at 1 to 15 ma with input voltages of 8 to 12 v over the temperature range -10 to +40 C. Circuit design and derivations for temperature compensation using thermistors and silicon resistors are covered in detail along with general design criteria for low-voltage regulators. (Author)

A description is given of the transmitter ModSPM, referred to as spin transmitter. Essentially it is a negative-grid oscillator employing two triodes in balanced circuit driving a split-loop antenna. It is used for measuring the rate of spin of the XM390 projectile and requires little or no modification of the vehicle. Frequency of operation is approximately 220 to 230 mc and radiated power of the unit is 200 mw. Configuration of the test site and location of the transmitter were such that toroidal nulls and maxima were recorded by a receiving station. The spin rate of the vehicle is equal to the number of nulls provided by one-half the flight time. (Author)

The designer of a new and complex instrument for use in missiles is unable to predict the probable percentages of successful operation from tests because of the small number of models available. Analysis of the physical basis for high reliability suggests that confidence in an instrument can be obtained by a method of complete environmental testing that is formulated mathematically ck, *Instrumentation, Satellites, Subminiature electron tubes, *Test equipment. The designer of a new and complex instrument for use in missiles is unable to predict the probable percentages of successful operation from tests because of the small number of models available. Analysis of the physical basis for high reliability suggests that confidence in an instrument can be obtained by a method of complete environmental testing that is formulated mathematically herein. This method has been applied to the testing of a family of high quality amplifiers in an environmental c amber permitting continuous and simultaneous variation of temperature, atmospheric pressure, and vibration, with the result that the designers obtained greatly increased confidence in the survival capability of the instrument. (Author)

A list is presented of current research and development projects on transducers and related systems compiled by the Aeronautical Systems Division, Wright-Patterson Air Force Base. (Author)

The Z-parameters of a transistor have been calculated in terms of the transistor T-equivalent circuit parameters. The calculations have been made for a frequency of 1.0 kc. In addition, each of the independent equivalent circuit parameters was halved and doubled while the rest were held constant, and the effect on the Z-parameters investigated. The results indicate that in the common base and common emitter configurations the input impedance depends on r sub b only, while the forward transfer impedance depends on r sub bAND R SUB E. The rest of the parameters are functions of r sub c and C sub c only. (Author)

Harry Diamond Laboratories conducted a Concept Formulation Program for the Hi-Performance Point-Detonating Fuze for Mortar and Artillery. The report contains descriptions of the fuze concept and its operation, results of laboratory and field tests, and analyses of safety, reliability, and producibility. (Author)

Two hundred 2D-binary dividers were evaluated and interconnected. Limited success was experienced with deposited metal and welded interconnection techniques. Jigs, fixtures and techniques employed are detailed. (Author)

A relationship has been noted between the transit times of ions in the glow discharge cathode fall and the frequency at which the reactance of the discharge changes from inductive to capacitive. The use of an electronic computer has enabled a more exact calculation of ion transit times. In the stationary state, effective i n transit times may be calculated directly from the field and current distributions across the gap. Dynamically, a small sinusoidal increment to the applied voltage across the tube may be used to calculate the impedance of a discharge gap. The ion transit time may then be determined from the phase lag between the electron current at the anode and ion current at the cathode. Satisfactory agreement for the ion transit times calculated by 2 methods is obtained. Experimental measurements of impedances of argon tubes have been made. Although it is difficult to obtain experimental data and calculations for the same current density range, preliminary data tend to support the proposed hypothesis relating the ion transit time and the frequency of zero reactance. (Author)

Contents: A 2D 30-Mc IF amplifier Azimuthal pattern of slotted array antennas on a cone Complementary filteringA new electrochemical system for high voltage, low ice $7.60 Department of the Army, Washington, D. C. MISSILES AND VENTURES INTO SPACE 1960-1961 REPORT. June 61, 81p. incl. illus. (Pamphlet no. 70-5-9) Unclassified report DESCRIPTORS: *Bibliography, *Guided missiles, Rocketurrent drain applications

A study was made of the problems of design and construction of Peltier temperature-control devices for use with Ordnance electronics. The principal features sought were (1) compatibility with conventional power supplies, particularly single-cell electrochemical systems, (2) techniques of assembly that are versatile with respect to physical configurations, and (3) techniques of assembly that are readily adaptable to production. A device for cooling was designed, built, and tested that operates from a supply voltage of 1.5 to 2.0 v at input powers up to about 6 w. Eighteen thermoelectric couples were connected in series electrically and in parallel thermally. Aluminum was used as the structural material, serving as both the base and the temperature-controlled chamber. An anodized layer on the aluminum provided good electrical insulation and thermal contact between the structural materials and thermoelectric elements. The circuit patterns were placed on the anodized layer by printed-circuitry techniques. By using jigs that are adaptable to quantity production, all 72 solder joints connecting the elements in series and to the structural materials were made in two operations. (Author)

A theoretical and experimental program has been conducted to determine an optimal antenna design for use with the MARDS (Medium Artillery Delivered Sensors) seismic detection system. Several models of MARDS antennas (vertically polarized) were evaluated over a frequency range of 100 to 200 MHz in the laboratory, in an anechoic chamber, and at an outdoor antenna range. Also, several test dipole and monopole antennas were designed and evaluated within this frequency range for optimum performance with the TDV (terminal delivered vehicle) of the system. (Author), Report on the Medium Artillery Delivered Sensor (MARDS) antenna.

UHF transmitters are extremely sensitive to physical deformation in that such deformation can cause a small change in reactance which can cause an appreciable change in frequency. Since ruggedized crystal-controlled oscillators limit the frequency shift to low levels, they permit early acquisition of artillery telemeter signals; a prototype transmitter was constructed to determine the degree of efficiency and compactness that could be obtained at L-band. A compact 1510-MHZ transmitter having an efficiency of 6 percent at an output power level of 160 mW is described. Physical dimensions are such that the transmitter can be readily potted in any artillery telemetry housing currently in use. Temperature compensation and gun ruggedization tests are currently in progress. (Author)

This paper describes a new high-voltage photovoltaic effect appearing in ferroelectric ceramics. A thin ceramic wafer illuminated uniformly produces a steady voltage across electrodes on the wafer edge. This is a new effect with possible applications. This effect could be used to produce very high voltages in a relatively uncomplicated fashion. Of greater importance, perhaps, is a possible potential for direct solar-to-electric energy conversion, although this would necessitate finding a material with considerably greater photovoltaic efficiencies over broader spectral regions.

The paper reports the effects of gamma and neutron irradiation on the power output and efficiencies of a commercial, high-power GaAs LED of current interest to system designers.

The complete simulation of the electromagnetic pulse, EMP, associated with a nuclear burst involves a number of interrelated parameters. The most obvious parameters are the waveform and the magnitude of EMP. However, if the system being subjected to the nuclear EMP is in a preionized region such as the ionosphere, it would also be necessary to simulate the ionization or dielectric constant of the medium surrounding the system such as a missile or satellite. In this work the authors investigate the feasibility of using an artificial dielectric consisting of a random distribution of inductively-loaded short dipoles to simulate the macroscopic electromagnetic properties of a simple Lorentz plasma.

The results of an experimental study of the material dynamic response of aluminum exposed to a high-fluence, low-energy, pulsed electron beam are presented. The experimental results are compared with calculations based on two equilibrium equation of state (EOS) models for metals in the melt regime. The first model is the simple Mie-Gruneisen (M-G) scheme for solids extrapolated into the liquid phase. The second model (the GRAY EOS) is a three-phase EOS which provides a more detailed and thermodynamically complete description of metals in the melt region. After the onset of melting the M-G theory differs appreciably from experiment, whereas the GRAY EOS provides good agreement. The results indicate that the P-V-T relationship during the melting process can be described by an equilibrium--but thermodynamically consistent--EOS model. (Modified author abstract)

The report contains the analysis and design of a unique optical-angle measuring device. This device was constructed to measure the error angle off boresight of a particular radar. Development of the device was divided into three major phases: optical design, photodiode considerations, and electronic processing. Laboratory tests of the device showed that it met and exceeded the angle accuracy requirement of plus or minus one milliradian. Additional uses for the system could include any application requiring angle alignment where it is feasible to mount a flashing light on the target to be measured. (Author)

A system for producing rectangular 0.5 MV pulses with rise times of about 1 nsec and duration between 5 and 20 nsec is described. A coaxial line is pulse-charged from a Martin-type autotransformer and then discharged by a fast-rise high pressure switch into a matched CuSO4 load resistor. A low-inductance capacitive voltage divider allows monitoring of the pulse. The jitter and delay in the discharge switch total less than a microsecond, allowing synchronization with other events. The system has been in use for 1-1/2 years with satisfactory results. (Author)

The elements (circuit models, condition for damage, or damage thresholds, of semiconductor components, circuit analysis codes) of a method (circuit-failure analysis) for determining damage in an electronic system from a signal induced by an electromagnetic pulse (EMP) are discussed. The state of the art in the areas of circuit models, damage thresholds, etc., is compared with the information and capability required for circuit-failure analysis. Results of research into second breakdown are discussed to the extent they relate to the condition for damage of junction components from electrical transients. (Modified author abstract)

The feasibility of using metal oxide varistors in electromagnetic pulse surge suppression connectors is currently being investigated. Toward that end, dielectric constants of four varistor types are found to be between 700 and 1000 at 1 kHz, decreasing by approximately 25 percent at 65 MHz. Dielectric constants as a function of temperature (-65 to 165F) are also reported. When used as the suppression element in a type N coaxial connector, the large capacitance will limit transmission bandwidth to frequencies below 10 MHz. (Author)

A method is given for the identification and isolation of anomalous data points in measurements that are being processed by a computer. A general discussion of the wild hare problem is presented, followed by a mathematical section and a section describing a computer program written in APL language which embodies the method. (Author)

A preliminary investigation of a proposed flaw detection technique was conducted. Conventional flaw-detection schemes employ piezoelectric transducers and use the reflection of acoustic energy inside the sample to locate irregularities. The method generally requires positioning the item in a testing tank or in a flowing-fluid test fixture to facilitate better input and output coupling of the acoustic energy. This requirement, which represents a serious drawback in the testing procedure, is completely avoided in the proposed scheme. The proposal entails the use of a laser to launch an acoustic wave in the test object, and a separate laser interferometer system to detect the reflected wave. The required rough surface interferometer has been successfully operated and may have applications other than proposed here. Tests were also made on the optical generation of acoustic waves, and results indicate that further consideration of the proposed system is merited. (Author)

The diffraction of an acoustic surface wave by a wedge of fused quartz is analyzed. Theoretical results are given for wedge angles up to 180 deg, showing almost complete transmission of surface waves for a wedge angle of 90 deg. A new, sensitive optical technique for measurement of acoustic wave transmission and standing wave ratio of surface waves provides experimental verification of the theory. This technique, using two coherent light beams focused on a fused quartz surface, is also useful for direct recording of attenuation, harmonic content and other propagation characteristics of acoustic surface waves. (Author)

A new type of electro-fluidic transducer is evaluated, which uses the heat dissipation from an electric coil in a capillary passage to change the viscosity of the fluid passing through the passage. A transfer function for the transducer is developed crudely, and static measurements on two different sized models show good agreement with calculations. The capillary electro-fluidic transducer has high static sensitivity but low bandwidth. Electrical powers of less than 0.100 W may be converted to sizeable fluid signals; however, the bandwidth of the transducers tested was only about 1.0 Hz. (Author)

An analysis has been made of the optical spectrum of Tm(3+) in YVO4. The approach taken was to describe the Tm(3+) free-ion energy levels as completely as possible and then to describe the effects of the crystal field on these levels. The results gave a new interpretation of the triplet H4 and triplet H5 multiplets and gave g factors in good agreement with the measurements. The effects of the hyperfine interaction and the spin-crystal-field interaction on the energy levels are discussed. (Modified author abstract)