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Youngbluth, O., Jr.

Publications and source records attributed to Youngbluth, O., Jr..

10 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1981

Ozone profiles from tethered balloon measurements in an urban plume experiment

NASA Langley Research Center used two tethered balloon systems to measure ozone in the general area of Norfolk, Va. The large balloon system which has an altitude range of 1,500 meters was located at Wallops Island, Va., and the smaller balloon which has an altitude range of 900 meters was located at Chesapeake, Va. Each balloon system measured ozone, temperature, humidity, wind speed, and wind direction from ground to its maximum altitude. From these measurements and from the location of the balloon sites, areas of ozone generation and ozone transport may be inferred. The measurements which were taken during August 1979 are discussed as well as the measurement techniques.

Youngbluth, O., Jr.↗
NASA NTRS1979

A versatile burst generator for LDV

A laser-Doppler velocimeter (LDV) burst generator developed for calibration of an LDV before an actual test is described. This generator uses voltage-controlled oscillators to produce the information frequency up to 1 MHz and the pedestal frequency up to 10 MHz. The amplitude and the frequency of each signal can be adjusted independently, and the generator is capable of producing a single burst or a variety of periodic and aperiodic bursts. Variable symmetry in the burst signal can be introduced to the point of producing the 'double-pulse' burst. An LED display is used for the readout of the information and the pedestal frequencies.

Youngbluth, O., Jr.↗
NASA NTRS1978

Versatile LDV burst simulator

A device for generating burst signals is reported that can be used to determine whether or not a laser Doppler velocimeter is operating properly. A high frequency signal which corresponds to the information frequency of the laser Doppler velocimeter is modulated by a low frequency signal to provide an envelope for the high frequency signal. The high frequency signal is modulated by any modulator means such as, for example, an analog multiplier. The low frequency signal is added to the modulated signal to provide pedestals for the resulting series of burst pulses. The means are provided for selecting different combinations of these burst signals. Also means are provided for making the burst signals asymmetrical as desired. In addition, means are provided for varying the frequencies, and amplitudes of the information, envelope and pedestal frequency signals in the burst signals.

Youngbluth, O., Jr.↗
NASA NTRS1977

Burst simulator for laser-Doppler velocimeter

Device allows for precheck of velocimeter electronics. Device uses voltage-controlled oscillators to generate fundamental frequency and pedestal frequency independently. Magnitude of each signal is adjustable. System allows variable asymmetry in burst signal to point of producing "double-pulse burst."

Youngbluth, O., Jr.↗
NASA NTRS1977

Photodiode and photomultiplier areal sensitivity anomalies

Several silicon photodiodes and photomultipliers were tested to determine signal variations as a light spot was scanned over the photosensitive surface of these detectors. Qualitative and quantitative data is presented to demonstrate the areal sensitivity anomalies. These anomalies are related back to the fabrication techniques of the manufacturers.

Youngbluth, O., Jr.↗
NASA NTRS1975

Color-coded area sensitivity maps of photomultipliers

Technique was devised specifically for testing photomultipliers and other photodetectors, but it could also be used to color code any type of mapping data, such as weather or topographical maps, thermal or pressure distributions on reentry surfaces, or any other three-dimensional data to be displayed in two-dimensional form.

Youngbluth, O., Jr.↗
NASA NTRS1974

Rapid measurements of areal sensitivity and areal spectral response of photodetectors

A flying spot scanning system was used to obtain areal sensitivity and areal spectral response data for nineteen photomultipliers. The efficiency of the electron optics was shown to be dependent upon the type of dynode structure used in the several photomultipliers. From areal sensitivity measurements it was found that the relative spectral response per unit area can vary over the face of a photomultiplier.

Youngbluth, O., Jr.↗