Low-power encoder system using electron beam derived from a cold source Final report
Low power encoder system using electron beam derived from cold source
Hafle, R.↗
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Quick-acting clutch disengages idle drive motor
Positive-drive, no drag, over-running clutch is developed to conserve power of idle motor in a low-power system using multiple drive motors. This device is useful where a number of shaft speeds are required with frequent shifting.
Stark, K. W.↗
Flow control valve is independent of pressure drop
Remote control of fluid flow in a low-power system is established by a flow control valve with a flapper and nozzle flow control. Constant rates are maintained despite fluctuating pressure across the valve.
Source record↗
Low power telemetry subcarrier oscillator.
Solid state voltage-controlled subcarrier oscillator for satellite and spacecraft low-power telemetry systems
TELEMETRY↗
Magnetic particle clutch controls servo system
Magnetic clutches provide alternative means of driving low-power rate or positioning servo systems. They may be used over wide variety of input speed ranges and weigh comparatively little. Power drain is good with overall motor/clutch efficiency greater than 50 percent, and gain of clutch is close to linear, following hysteresis curve of core and rotor material.
Fow, P. B.↗
A compact and low power coherent optical system for on-board spacecraft data processing.
Discussion of the design and performance of a compact low-power coherent optical data processing system suitable for spacecraft onboard applications. The system is a modification of the conventional optical data processing system in which a much more efficient solid state GaAs laser is substituted for the bulky and inferior He-Ne laser and paraboloidal mirror segments are substituted for the axially symmetric optical system of the conventional data processing system. Theoretical considerations are given to substantiate the improvement of performance aimed at in the modified system. Preliminary tests of the modified design being in progress indicate that a low power, rugged, small size optical system, capable of onboard spacecraft data processing, can be constructed by using off-axis paraboloidal mirror segments.-
Husain-Abidi, A. S.↗
Multimegabit Operation Multiplexer System
The Multimegabit Operation Multiplexer System (MOMS) is a high-data-rate PCM telemetry unit capable of sampling and encoding 60 scanning radiometer and four vidicon channels at 250 kilosamples/second and 5 megasamples/second, respectively. This sampling capacity plus the seven-bit quantization requires a total throughput rate of 40 megasamples/second and 280 megabits/second. To produce these rates efficiently, the system was divided into a pair of identical 140-megabit blocks. A low-power 20-MHz analog multiplexer and analog-to-digital converter were developed together with a video sample-and-hold that features an aperture time error of less than 50 psec. Breadboard testing of these basic building blocks confirmed the design prediction that the total system would consume 27 watts of power. Two 140-megabit output parts are suitable for quadriphase modulation.
Giri, R. R.↗
An analog-to-digital conversion system with a logarithmic characteristic
Detailed analysis of an analog-to-digital conversion system consisting of a linear converter and a logarithmic amplifier containing nonlinear elements. It is shown that the small-signal resolution of such a system is much greater than that of linear systems used under the same conditions. A design for a low-power analog-to-digital converter operating at medium speed with a large input signal variation field is outlined.
Bellomo, A.↗
Simplified propeller design for low-powered airplanes
The object of this report is to furnish the designer and builder of small airplanes a simple system for designing the propeller and making the drawing. An empirical design method is used, based on tests of model propellers in a wind tunnel and full scale tests of propellers in flight.
Weick, Fred E↗
The brayton cycle for space power
This paper reviews the basic features of the Brayton cycle and discusses the selection of such cycle parameters as working fluid, pressure, and temperature. System performance, weight, and reliability characteristics are then considered in order to determine the suitability of this type of system for the intended space applications. It is shown that the Brayton cycle can be considered suitable for low-power solar and intermediate-power nuclear applications where low specific weight is not a critical requirement. To achieve the low specific weights required for electrical propulsion missions, turbine-inlet temperatures in the 3000 R region at power levels in the 500–1000 kw range appear to be necessary.
ELECTRIC PROPULSION↗
Small, low power analog-to-digital converter
A small, low-power, high-speed, 8-bit analog-to-digital converter using silicon chip integrated circuits is suitable for use in airborne test data systems. The successive approximation method of analog-to-digital conversion is used to generate the digital output.
Dunn, R. D.↗
Space station communications using interplex modulation.
Description of a multichannel PCM-PSK-PM modulation scheme called interplex which reduces cross-modulation loss and excess carrier reference power of conventional systems when the number of channels is small. In systems with equal channels, interplex is more efficient when the number of channels is not greater than four. The number of channels which can be combined efficiently with interplex increases if there are many low-power channels and only one high-power link. The scheme can be implemented in existing systems without significant hardware changes and appears to be suitable for use in a multichannel space-station telecommunications system.
Butman, S.↗
High-Speed Oil Engines for Vehicles. Part III
Ignition-chamber engines and their fuel injection systems are investigated.
ENGINES, FUEL INJECTION↗
DESIGN TECHNIQUES FOR LOW-POWER TELEMETRY
Design for low power lunar telemetry communications system
COMMUNICATION↗
A Low-power High-efficiency Dc to Dc Converter
Low power high efficiency dc to dc converter- regulator for electronic systems
ELECTRONIC EQUIPMENT↗
Adaptive control circuit prevents amplifier saturation
Adaptive control circuit prevents saturation of push-pull output amplifiers used in low-power, low-torque suspension system. The adaptive control circuit senses how near the output amplifiers are to saturation and sets the B voltage in such a way as to keep them just clear of saturation.
Nondsieck, A. J.↗
Experimental performance of a low-power MPD arc thrustor
Low power magnetoplasmadynamic arc thrustor performance
PROPULSION SYSTEM PERFORMANCE↗
A narrowband, crystal controlled biomedical telemetry system.
A miniature, single-channel, crystal-controlled transmitter has been developed for biomedical applications. A narrow-band frequency modulation (plus or minus 7 kHz) of the RF is used to achieve maximum operating range with minimum transmitting power. The radiated power is limited to stay within the 50 microvolts/m at 15 m FCC requirement for low-power transmitters in the 88- to 108-MHz band. This technique offers a number of advantages. First only manufacturer's type approval is required for the device and the user does not need a license. Second maximum operating range can be achieved within the FCC power limitations by using a narrow-band that is consistent with the required medical information bandwidth. A third advantage in using the 88- to 108-MHz band is that the commercial FM stations are relatively widely spaced and carefully regulated so that by selecting the transmitter's frequency in the guard band between stations, minimum interference from other transmitter sources is encountered.
Westbrook, R. M.↗