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  • ItemRestricted
    Synchronous programmable sequencer (SPS)
    (Instituto Geofísico del Perú, 1978-09) Tobaja, E.; Woodman Pollitt, Ronald Francisco; Haseltine, D.
    The purpose of this document is lo provide the user, the maintenance engineer, and the system programmer with the necessary information for its maintenance and use. The document provides more information than would normally be required by the average experimental user. The latter may want to limit himself to reading the following "Short. Description" and taking a quick look at the rest of the document. The SPS has been implemented on a Harris universal interface wire wrap card. This card, bought from Harris, contains all the interface element’s needed to communicate to and from the computer. They are mounted in wire wrap IC sockets and wired lo their respective pins in the channel communications cable connectors. Since the card also contains a number of 16 and 14 pins wire wrap IC sockets, the SPS logic is implemented here by populating these sockets and interconnecting them.
  • ItemOpen Access
    Implementación de registrador digital para variometros tradicionales del tipo Eschenhagen
    (Instituto Geofísico del Perú, 2010-12) Vidal Safor, Erick; Rosales Corilloclla, Domingo
    El área de Geomagnetismo del Observatorio de Huancayo cuenta con variometros tradicionales mecánicos como sensor a imanes suspendidos y equilibrados los cuales perciben los cambios que ocurren en las distintas componentes del campo magnético que por ellos traviesan. Este tipo de magnetómetros utilizan un modo de registro por rebote de luz el cuál es registrado en un papel fotográfico. Los magnetómetros del tipo tradicional han demostrado ser buenos equipos de medición mostrando gran estabilidad en el tiempo, pero su diseño original demanda el uso de papel fotográfico. Hoy en día es escasa la producción de papel fotográfico por lo que la adquisición de este insumo se hace muy costosa. En la actualidad la tecnología ha desarrollado equipos que realizan el mismo trabajo pero de mayor resolución, velocidad de registro entre otros como los magnetómetros tipo FluxGate o de bombeo óptico, llevándolos al desuso a los magnetómetros mecánicos tradicionales del tipo Eschenhagen. De la misma manera que la tecnología ha contribuido con el desarrollo de nuevos equipos de registro, ésta también ha desarrollado los elementos necesarios que en su conjunto son capaces de reproducir el comportamiento del papel fotográfico haciendo posible la continuidad del registro de los magnetómetros tradicionales mediante medios óptico/electrónicos el cuál brinda la oportunidad a que equipos históricos continúen su funcionamiento registrando la variación del campo magnético terrestre y los datos puedan ser observa dos en tiempo real."
  • ItemOpen Access
    Control de sensibilidad de los magnetovariografos mediante observaciones absolutas
    (Instituto Geofísico del Perú, 2010) Rosales Corilloclla, Domingo; Vidal Safor, Erick; Orihuela Lazo, Silvano
    Uno de los aspectos más importante en un Observatorio Geomagnético es el control de la calidad de los datos que se registran, para ello a los instrumentos geomagnéticos se les aplica diversas técnicas de control para evaluar su performance. En este caso realizamos un control de calidad a los magnetovariografos como son: Sensibilidad, linealidad y estabilidad. Se aplica una técnica que permite determinar el estado operativo de los magnetovariografos sin la necesidad de tener que parar el registro de datos, evitando de esta manera la pérdida de datos no registrados y tener que manipular los magnetovariografos físicamente para conocer su estado de operatividad.
  • ItemOpen Access
    Actualización de instrumento óptico FPI en estación óptica del ROJ
    (Instituto Geofísico del Perú, 2010-09) Navarro, L.; Veliz, Oscar
    En el presente reporte se detalla los cambios realizados al instrumento óptico Interferometro Fabry-Perot de la estación óptica del Radio Observatorio de Jicamarca (11°57'31.38"S, 76°51'36.84"W) mediante los cuales se ha incrementado su sensibilidad al doble de órdenes interferométricos de la línea OI de la luminiscencia nocturna.
  • ItemRestricted
    Observations of E-region irregularities with ST-Radar in Piura Perú
    (Instituto Geofísico del Perú, 1993) Woodman Pollitt, Ronald Francisco; Rodriguez, Rodolfo; Balsley, Ben B.
    During a short period around the first days of february the ST radar located in the campus of the Universidad de Piura, Piura (5°S. 80,5° w), Perú, was pointed in a direction perpendicular to the magnetic field. The goal was to make a quick evaluations of the instrument as a tool to study the E-region at this altitudes. The radar has an antenna of 100m x 100m, with a transmitter with a peak power of 50 kW. A pulse width of 8 usec was used giving a range resolution of 1.2 km. The radar interpulse period was set at 1 msec, given a maximum Nyquist frequency corresponding to a doppler shift of 150 m/sec. The observations lasted several days, but only the last were successful. The first trials were made centered at noon time, influenced by our experience with the E-region echoes at the equator, since this is the time at which the equatorial echoes are the strongest. We obtained no echoes during this trials.
  • ItemOpen Access
    Report of MSG-6 on the scientific aspects of an international equatorial observatory (IEO)
    (Instituto Geofísico del Perú, 1983) Balsley, B.B.; Blamont, J.; Forbes, J.M.; Geller, M.A.; Hirota, I.; Vincent, R.A.; Woodman Pollitt, Ronald Francisco
    MSG-6 has been set up to study this on the basis that there is need to have observatories very close to the equator so that we may understand equatorial dynamics much more precisely than we do now. Such observatories, which are equipped with MST radars, lidar and other facilities, should be constructed and operated th rough international cooperation. Specific require­ments for the observation of equatorial middle atmosphere dynamics were discussed at the Workshop held 10-12 May 1982 at Estes Park, CO, USA, as will be shown in Section 2. MSG-6 has further worked on the problem, obtaining the opinions of each member as to the following questio ns: (1 ) locations of IEOs; (2) specification of the faciliti es at IEOs; and (3) finanical support on the construction and the maintenance of IEOs.The proposed locations for IEOs are, in alphabetical arder, Christmas Island, Galapagos Island, Kourous, Nauru and Tumbes (or Iquitos).
  • ItemOpen Access
    Radio star scintillations at 50MHz. Produced by electrojet irregularities (Poster)
    (Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 1994) Woodman Pollitt, Ronald Francisco; Aquino Q., F.; Villanueva R., F.; Sarango A., M.
    In connection with the Shoemaker-Levy comet collision with Jupiter, scans of Hydra-A, a radio star, was made with the Jicamarca large antenna array (50 MHz), for calibration purposes. The scans were made during the day when electrojet conditions were present. lt was found that the power signature of the star scintillated as much as 40 percent with a time scale of the order of ten seconds. The scintillation is attributed to large scale E-region irregularities in the km length scale drifting at a speed of 136 m/sec. This discovery gives usan additional tool for the study of the important large scale primary irregularities in the electrojet.
    Palabras clave:RadioCalibrationStars
  • ItemOpen Access
    Programación de la transformada rápida de Fourier de base 4 y 8 para procesamiento en tiempo real
    (Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 1975-01) Hoz, César La; Woodman Pollitt, Ronald Francisco
    Se informa sobre la implementación de la transformada Rápida de Fourier para su aplicaci6n en el estimado de fun­ciones de densidad espectral de ecos ionosféricos en tiempo real. Se hace una descripción del algoritmo básico mostrándose que la eficiencia de la TRF es proporcional por lo menos a NlogrN en lugar de N Se describen los criterios que conducen a una estructura óptima del programa, estableciéndose las relaciones que dan el número de operaciones exactas en el cálculo de la TRF de base arbitraria, Se in­forma que el programa de base 8 admite un ancho de banda en tiempo real de 6 kHz, ó el procesamiento espectral de 15 al turas de ecos ionosféricos con un periodo entre-pulsos de 2.5 mseg.
  • ItemOpen Access
    Phase measurement/display subsystem for the Apollo re-entry tracking system
    (NASA, 1963-12-13) Woodman Pollitt, Ronald Francisco
    A combined system consisting of an Interferometer and a Range System has been proposed (Reference #1) for tracking the Apollo spacecraft during the re-entry phase. The system herein discussed processes the output of the above system and performs the following functions.
  • ItemOpen Access
    Tracking of radio stars with the minitrack system
    (Editor no identificado, 1963-07) Woodman Pollitt, Ronald Francisco
    This report will discuss the possibilities of using the Minitack system with a wider predetection Bandwidth in conjunction with the Narrow Band Tracking Filter for the tracking of Radio Stars.
  • ItemOpen Access
    The equatorial electrojet: a bibliography
    (Instituto Geofísico del Perú, 1990) Alvarez, Juan; Woodman Pollitt, Ronald Francisco
    This work has been carried out for the purpose of transferring scientifíc knowledge on the Equatorial Electrojet to the engineering community who works in the fíeld of telecommunications. The skillful knowledge acquired on this subject, through several decades, by the intemational scientific community, by the Instituto Geofísico del Peru and, specially, by the Jicamarca's Radio Observatory, has made possible the use of the Equatorial Electrojet for communication purposes. With this motivation, the Instituto Nacional de Investigacion y Capacitacion de Telecomunicaciones (INICTEL) and the Instituto Geofísico del Peru (IGP) have begun a transference of technology project. As a fírst step, we have started compiling bibliography which assembles the scientifíc knowledge on this fíeld for the interested technical community. This compilation gathers titles and authors of studies which directly analyze the Equatorial Electrojet or the equatorial E-Region of the ionosphere. This work starts chronologically with an article of Chapman S. (1951), where the equatorial "anomaly" that is observed on E-Region in the surroundings of the magnetic equator is named as Equatorial Electrojet. From that time several publications have appeared which study this phenomena on an experimental and theoretical basis.
  • ItemOpen Access
    Study of equatorial scintillations. A progress report
    (Goddard Space Flight Center, 1972-12) Pomalaza, José; Woodman Pollitt, Ronald Francisco; Tisnado, Gilberto; Nakasone, Eduardo
    Observations of amplitude scintillations produced by F-Region ionopheric irregularities has been performed at the Ancón observatory (Latitude - 11°46', longitude 77°9') since 1968. At first minitrack interferometric records at 137 MHz were used in the studies. The purpose of this report is to present results of some of the work performed on the data during the period late 1971 and 1972.
  • ItemOpen Access
    Statistical study of equatorial scintillations at Ancon, Peru
    (Instituto Geofísico del Perú, 1970) Tisnado, G.; Woodman Pollitt, Ronald Francisco; Pomalaza, J.
    The 136 MHz interferometric system at the past NASA Satellite Track­ing Station in Ancón, Perú, consists of two orthogonal baselines aligned along the North-South and East-West directions. A sizable number of interferometric records intended far operation­al tracking was spoiled by large amplitude and phase fluctuations. Ir - regularities In the ionosphere, those associated with the spread-F phenomena, are the cause of these fluctuations (scintillations). In most of the distorted records the North-South baseline inter­ferometer shows only a slight distort(on from the expected satellite graph whlle in the East-West interferometer the distortions are severe. This clearly shows the anisotropy of the irregularities and that they are elongated and aligned the magnetic field lines(Z) as have been found by other authors. The absence of North-South phase distortions when East­West distortions are present facilitates the detection of weak scintillations against the background noise. Far the purpose of this report the East-West baseline interferometric distortion was taken as an indication of scintillations.
  • ItemOpen Access
    Implementación del software para el sistema de digitalización del ROJ
    (Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 1973) Hoz, César La; Woodman Pollitt, Ronald Francisco
    Se ha escrito un conjunto de rutinas en el lenguaje Assembler de la computadora Datacraft 6024/3 (Ref. 1) con la finalidad de facilitar el uso eficiente del nuevo Sistema de Digitalización (Ref. 2) del R.O.J. Estos programas pueden ser invocados por otro progra ma conductor escrito en lenguaje FORTRAN. Este programa conductor es confeccionado apropiadamente por el usuario de acuerdo a su objetivo. Las rutinas que se han escrito son de un carácter completamente general. Hacen uso efectivo de las más avanzadas opciones del Sistema DC 6024/3, tales como uso extensivo de interrup­ciones y el empleo de Controladores de Bloque Automáticos (Automatic Block Controllers, ABC Ref. 3), que operan con el peculiar y eficiente modo de "robar un ciclo" a la Unidad Central de Procesamiento (CPU) (Ref. lf). Estas características permiten las más variadas aplicaciones del Sistema de Digitalización, obteniéndose importantes ventaja,,especialmente en el aprovechamiento máximo de la velocidad de la computadora, y posibilitándose el procesamiento en tiempo real o en línea de los datos digitalizados, en una suerte de compartición de tiempo (Time Sharing).
  • ItemOpen Access
    Las ciencias y tecnologías espaciales en el Perú
    (Comisión Nacional de Investigación y Desarrollo Aeroespacial, 1974) Woodman Pollitt, Ronald Francisco
    Lo función de este informe es le de hacer un análisis de los activi­dades espaciales, las actividades directamente conectadas o ellos, y los campos en que pueden ser aprovechados, pero proporcionar a la Comisión elementos de juicio que le permiten delimitar y programar sus actividades y tomar los decisiones necesarios a la brevedad posible.
  • ItemOpen Access
    Die prozebsteuerung und datenerfassung der SOUSY-VHF-Radaranlage
    (Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 1978) Kugel, R.P.; Shmidth, G.; Woodman Pollitt, Ronald Francisco
    Central unit of the radar control and data acquisition is a 21M08 hewlett packard minicomputer with a real-time-II and file-manager execute system. Together with standard periphery and analog-digital converter, a radar controller controls the preprocessor, and the antenna control are connected to the computer. The radar controller controls the synchronous radar cycle and can generate phase-coded signals. The processor reduces the data rate of 4 MW/s from the AD-converter by a factor of thousand by averaging the signals. In addition the preprocessor can decode phase-coded signals. He averaging has the effect of a combfilter.
  • ItemOpen Access
    Donald T. Farley, appleton prize 1996: his contributions to equatorial aeronomy
    (Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 2000-05) Woodman Pollitt, Ronald Francisco
    Texto homenaje a Donald T. Farley, ganador del Premio Appleton en el campo de la física ionosférica, entregado por la Council of the Royal Society por las recomendaciones del Board of officers de URSI.
    Palabras clave:AeronomyRadarF region
  • ItemOpen Access
    ¿Dónde, cuándo y cómo ver el cometa Halley?
    (Instituto Geofísico del Perú, 1986) Woodman Pollitt, Ronald Francisco
    Nota informativa acerca del avistamiento del cometa Halley en Lima, Perú.
  • ItemOpen Access
    Jicamarca incoherent scatter observations during the march 1970 storm
    (World Data Center A, 1971-04) Woodman Pollitt, Ronald Francisco
    The purpose of this note is to report on ionospheric observations taken at Jicamarca (lº N Magnetic Latitude) during the March 8, 1970 magnetic storm. This report includes measurements of the electron density, electron temperature and vertical drift (or E-W electric field) for the 7, 8 and 9 of March 1970. These measurements are complemented by C-4 ionograms and magnetic field measurements taken at the Huancayo Observatory which is located at the same magnetic latitude 100 km east from the Jicamarca Observatory. We are including Huancayo AH magnetograms to illus­trate our discussion. The data reported here are still under study and it is being reported in response to the re­quest of the World Data Center A, Upper Atmosphere Geophysics, in its effort to gather world-wide data taken during the magnetic storm in a single publication. Therefore, we shall present the ex­perimental facts limiting our discussion and conclusions to those which can be ,derived from simple inspection of the records. The techniques used to gather the data have been reported previously. The electron densities have been obtained using the Faraday rotation method and the electron temperatures using the cross correlation technique, both systems have been described by Farley [1969a,b). The technique to obtain the vertical drift (E-W electric field) is described by Woodman and Hagfors [1969). The three parameters were measured almost simultaneously. We do not have quiet day measurements of density and temperature sufficiently close to the day of the storm to be taken as a control day. The reader will have to refer to the statistical be­havior of these parameters as measured at Jicamarca and reported by J. P. McClure, D. T. Farley and R.Cohen ll970J and J. P. McClure [1970). We have included here the statistical behavior of verti­cal drifts for the same season taken from Woodman [1970).
  • ItemOpen Access
    Interfase para acoplar un sistema de conversión Analógico/Digital a una computadora DATACRAFT 6024
    (Instituto Geofísico del Perú, Radio Observatorio de Jicamarca, 1972) Guillén C., Alberto; Woodman Pollitt, Ronald Francisco
    Muchos procesos para su estudio óptimo por medio de computadoras requieren de diferentes sistemas de transducción. El presente trabajo describe el diseño de un sistema digital para acoplar un sistema de mul­plex y de conversión analógica/digital a una computadora, permitiendo el procesamiento si­multáneo de hasta 8 señales y con velocidades de hasta 500 mil muestras por segundo. El diseño ha aplicado al sistema de computación del Radio Observatorio de Jicamarca, uno de los obser­vatorios del Instituto Geofísico del Perú. Este sistema permitirá el procesamiento de señales analógicas producto de diferentes proyectos de investigación científica tales como física ionosfé­rica, sismología, infrasonido, cintilaciones, ocea­nografía, etc. El sistema diseñado podría adecuarse para el acoplamiento de otros sistemas de conversión analógica a otras computadoras involucradas en proyectos de investigación científica.