Mcmahon, Morgan E
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Switched-Mode Power Supply - Wikipedia, the Free Encyclopedia
Switched-mode power supply - Wikipedia, the free encyclopedia Log in / create account Article Discussion Read Edit Switched-mode power supply From Wikipedia, the free encyclopedia For other uses, see Switch (disambiguation). Navigation A switched-mode power supply (switching-mode Main page power supply, SMPS, or simply switcher) is an Contents electronic power supply that incorporates a switching Featured content regulator in order to be highly efficient in the Current events conversion of electrical power. Like other types of Random article power supplies, an SMPS transfers power from a Donate to Wikipedia source like the electrical power grid to a load (e.g., a personal computer) while converting voltage and Interaction current characteristics. An SMPS is usually employed to efficiently provide a regulated output voltage, Help typically at a level different from the input voltage. About Wikipedia Unlike a linear power supply, the pass transistor of a Community portal switching mode supply switches very quickly (typically Recent changes between 50 kHz and 1 MHz) between full-on and full- Interior view of an ATX SMPS: below Contact Wikipedia off states, which minimizes wasted energy. Voltage A: input EMI filtering; A: bridge rectifier; regulation is provided by varying the ratio of on to off B: input filter capacitors; Toolbox time. In contrast, a linear power supply must dissipate Between B and C: primary side heat sink; the excess voltage to regulate the output. This higher C: transformer; What links here Between C and D: secondary side heat sink; efficiency is the chief advantage of a switched-mode Related changes D: output filter coil; power supply. -
The Arrival of the First Film Sound Systems in Spain (1895-1929)
Journal of Sound, Silence, Image and Technology 27 Issue 1 | December 2018 | 27-41 ISSN 2604-451X The arrival of the first film sound systems in Spain (1895-1929) Lidia López Gómez Universitat Autònoma de Barcelona [email protected] Date received: 10-01-2018 Date of acceptance: 31-03-2018 PALABRAS CLAVE: CINE MUDO | SONIDO | RecepcIÓN | KINETÓFONO | CHRONOPHONE | PHONOFILM KEY WORDS: SILENT FILM | SOUND | RecepTION | KINETOPHONE | CHRONOPHONE | PHONOFILM Journal of Sound, Silence, Image and Technology | Issue 1 | December 2018. 28 The arrival of the first film sound systems in spain (1895-1929) ABSTracT During the final decade of the 19th century, inventors such as Thomas A. Edison and the Lumière brothers worked assiduously to find a way to preserve and reproduce sound and images. The numerous inventions conceived in this period such as the Kinetophone, the Vitascope and the Cinematograph are testament to this and are nowadays consid- ered the forerunners of cinema. Most of these new technologies were presented at public screenings which generated a high level of interest. They attracted people from all social classes, who packed out the halls, theatres and hotels where they were held. This paper presents a review of the newspa- per and magazine articles published in Spain at the turn of the century in order to study the social reception of the first film equip- ment in the country, as well as to understand the role of music in relation to the images at these events and how the first film systems dealt with sound. Journal of Sound, Silence, Image and Technology | Issue 1 | December 2018. -
History of Communications Media
History of Communications Media Class 5 History of Communications Media • What We Will Cover Today – Photography • Last Week we just started this topic – Typewriter – Motion Pictures • The Emergence of Hollywood • Some Effects of the Feature Film Photography - Origins • Joseph Nicephore Niepce –first photograph (1825) – Used bitumen and required an 8-hour exposure – Invented photoengraving • Today’s photolithography is both a descendent of Niepce’s technique and the means by which printed circuits and computer chips are made – Partner of Louis Daguerre Photography - Origins • Louis Daguerre – invented daguerreotype – Daguerre was a panorama painter and theatrical designer – Announced the daguerreotype system in 1839 • Daguerreotype – a photograph in which the image is exposed onto a silver mirror coated with silver halide particles – The first commercially practical photographic process • Exposures of 15 minutes initially but later shortened – The polaroid of its day – capable of only a single image Photography – Origins • William Henry Fox Talbot – invented the calotype or talbotype – Calotype was a photographic system that: • Used salted paper coated with silver iodide or silver chloride that was developed with gallic acid and fixed with potassium bromide • Produced both a photographic negative and any desired number of positive prints Photography – Origins • Wet Collodion Process - 1 – Invented in 1850 by Frederick Scott Archer and Gustave Le Grey – Wet plate process that required the photographer to coat the glass plate, expose it, -
Radio Digest, 1924-1925
B64714 6 DEC 271924 Aerial Aids for Christmas Set Buyers—J. E. Owen; New Het-duo-gen Circuit; "X" Wire—Key to Neutrodyne Success ; Details of $1,000.00 Gold Award Set Radio Di EVERY m= PROGRAMS TEN I CENTS REG. U. S. PAT. OFF. & DOM. OF CANADA \/,J YT Copyright 1924 VOl. -A.1 By Radio Digest Publishing Co. SATURDAY, DECEMBER 27, 1924 No. 12 NEW SET—FIND OF YEAR HET-DUO-GEN TUNES EITHER COAST EASILY Selectivity C. E. Brush Uses Six Tubes in Decidedly New Hook-Up —Tells How to Build Meet the Het-duo-gen! The set that really brings in what you want when you want it has come to light at last. A complete surprise be- cause its development is so different from the lines along which most ex- perimenters were known to be working. Combining the advantages of the hetero- dyne with regeneration on two tubes, C. E. Brush, of Chicago, has achieved a degree of selectivity that is almost miraculous. The sensitivity seems con- sistently to equal that of an eight tube PHONE CONNECTION super-heterodyne while the volume from three stages of audio frequency ampli- fication is more than enough for dancing. LONDON -NEW YORK A large loud speaker is required to handle it. Once the circuit is explained and the NEW STATION READY FOR operation understood, it all seems so simple that one wonders why it hasn't SERVICE NEXT YEAR been done before. Cost? The cost to (Continued on page 2) Will Use 4,000,000 Watts Power for Transoceanic Talking—Toll Charge Approximately $25 LONDON, Eng.—It is not only possible, but absolutely certain that in a year's time, any man in England can pick up the ordinary telephone in his house and speak to a friend in New York. -
“R.M.S. Titanic” Hanson W
“R.M.S. Titanic” Hanson W. Baldwin I The White Star liner Titanic, largest ship the world had ever known, sailed from Southampton on her maiden voyage to New York on April 10, 1912. The paint on her strakes was fair and bright; she was fresh from Harland and Wolff’s Belfast yards, strong in the strength of her forty-six thousand tons of steel, bent, hammered, shaped, and riveted through the three years of her slow birth. There was little fuss and fanfare at her sailing; her sister ship, the Olympic—slightly smaller than the Titanic— had been in service for some months and to her had gone the thunder of the cheers. But the Titanic needed no whistling steamers or shouting crowds to call attention to her superlative qualities. Her bulk dwarfed the ships near her as longshoremen singled up her mooring lines and cast off the turns of heavy rope from the dock bollards. She was not only the largest ship afloat, but was believed to be the safest. Carlisle, her builder, had given her double bottoms and had divided her hull into sixteen watertight compartments, which made her, men thought, unsinkable. She had been built to be and had been described as a gigantic lifeboat. Her designers’ dreams of a triple-screw giant, a luxurious, floating hotel, which could speed to New York at twenty-three knots, had been carefully translated from blueprints and mold loft lines at the Belfast yards into a living reality. The Titanic’s sailing from Southampton, though quiet, was not wholly uneventful. -
Ethics and Operating Procedures for the Radio Amateur 1
EETTHHIICCSS AANNDD OOPPEERRAATTIINNGG PPRROOCCEEDDUURREESS FFOORR TTHHEE RRAADDIIOO AAMMAATTEEUURR Edition 3 (June 2010) By John Devoldere, ON4UN and Mark Demeuleneere, ON4WW Proof reading and corrections by Bob Whelan, G3PJT Ethics and Operating Procedures for the Radio Amateur 1 PowerPoint version: A PowerPoint presentation version of this document is also available. Both documents can be downloaded in various languages from: http://www.ham-operating-ethics.org The PDF document is available in more than 25 languages. Translations: If you are willing to help us with translating into another language, please contact one of the authors (on4un(at)uba.be or on4ww(at)uba.be ). Someone else may already be working on a translation. Copyright: Unless specified otherwise, the information contained in this document is created and authored by John Devoldere ON4UN and Mark Demeuleneere ON4WW (the “authors”) and as such, is the property of the authors and protected by copyright law. Unless specified otherwise, permission is granted to view, copy, print and distribute the content of this information subject to the following conditions: 1. it is used for informational, non-commercial purposes only; 2. any copy or portion must include a copyright notice (©John Devoldere ON4UN and Mark Demeuleneere ON4WW); 3. no modifications or alterations are made to the information without the written consent of the authors. Permission to use this information for purposes other than those described above, or to use the information in any other way, must be requested in writing to either one of the authors. Ethics and Operating Procedures for the Radio Amateur 2 TABLE OF CONTENT Click on the page number to go to that page The Radio Amateur's Code ............................................................................. -
Chrysler Corporation Tunes in with "Transistor-Ized" Music
By Rick Hirsh Chrysler Corporation Tunes in with "Transistor-ized" Music Chrysler Corporation was the "first" car manufacturer, to advertise the use of transistors in its production car models. Chrysler and Philco Corporations had originally developed and produced an all- transistor car radio (Mopar model 914HR) in 1955. This “ground breaking” news was first announced in the Wall Street Journal newspaper on April 28, 1955. And it was an “option” for the new 1956 Chrysler and Imperial car models, that became available in its showrooms starting on October 21, 1955. But, it was short- lived, for Chrysler had decided to discontinue its new all-transistor car radio "option" before the end of 1956, due to poor sales and its expensive manufacturing costs to produce. Some of the advantages of using all-transistors versus tubes for car radios … Instant radio turn-on power versus 30-second warm-up time. Uses 90% less battery power supply. Produces less heat than conventional vacuum tube car radios. Uses no noisy vibrator power supply, which supplies the high-voltage needed for the radio's conventional vacuum tubes and was also the number one radio part to fail. Chrysler Corporation had decided that transistors were still the cutting edge of technology and was the wave of the future. And they had made the decision during the fall of 1956, to go with a newly developed “transistorized-hybrid” (vacuum tubes + transistors) car radio design, for all of its divisions and new 1957 car models. Large vacuum tube manufacturers like Tung-Sol had started to worry about its future, with regards to the newly developed transistor technology that would replace its vacuum tubes in car radios. -
Replacing the Mechanical Vibrator in the DY-88 Power Supply for the GRC-9 Transceiver by Craig Vonilten, N6CAV with Contributions by Tom Murphy W6TOM
Replacing the Mechanical Vibrator in the DY-88 Power Supply for the GRC-9 Transceiver by Craig Vonilten, N6CAV with contributions by Tom Murphy W6TOM As older mechanical vibrators fail (and they will ALL fail at some point) a suitable replacement is needed. I have gone through several different ways of doing this in keeping my DY-88 power supply functional. Initially I did this by repairing the mechanical units (opening and cleaning their contacts), then building my own solid state replacement and finally using ‘kits’ and designs by other amateur radio enthusiasts. All approaches have some merit…but I have settled on an indestructible approach using a small module made by Aurora Design originally intended for restoring commercial automotive radios. Consequently, this article is really more mechanical in nature than it is electrical ‘design’ related. I am using this module because it is incredibly well designed for this application. It has eliminated any desire to “roll my own”. This module is microprocessor controlled. Yes, you read that correctly…it has an onboard microprocessor that provides numerous advantages over traditional designs based on RC timed ‘blind’ switching or 555 timer solutions. With a microprocessor on-board, this module brings some “smarts” to the traditional switching circuit such as: dead-band control, delayed start, soft start, delayed restart, short circuit protection and over-power protection. Better yet…it can help protect downstream devices like the transformer (which would normally be destroyed by a traditional vibrator or solid state module if a buffer capacitor were to fail to a short circuit…not uncommon). -
Redalyc.Los Inicios Del Cine Sonoro Y La Creación De Nuevas Empresas Fílmicas En México (1928-1931)
Revista del Centro de Investigación. Universidad La Salle ISSN: 1405-6690 [email protected] Universidad La Salle México Vidal Bonifaz, Rosario Los inicios del cine sonoro y la creación de nuevas empresas fílmicas en México (1928-1931) Revista del Centro de Investigación. Universidad La Salle, vol. 8, núm. 29, enero-junio, 2008, pp. 17- 28 Universidad La Salle Distrito Federal, México Disponible en: http://www.redalyc.org/articulo.oa?id=34282903 Cómo citar el artículo Número completo Sistema de Información Científica Más información del artículo Red de Revistas Científicas de América Latina, el Caribe, España y Portugal Página de la revista en redalyc.org Proyecto académico sin fines de lucro, desarrollado bajo la iniciativa de acceso abierto Los inicios del cine sonoro y la creación de nuevas empresas fílmicas en México (1928-1931) Mtra. Rosario Vidal Bonifaz Centro Universitario de Ciencias Sociales y Humanidades, Universidad de Guadalajara E-mail: [email protected] Recibido: Septiembre 9, 2007. Aceptado: Diciembre 7, 2007 RESUMEN El cine como industria tuvo su plataforma en las primeras décadas del siglo XX, y la imagen fue su principal elemento de identidad. No será hasta la crisis de 1929 y la necesidad de financiamiento que los empresarios voltean su mirada a la integración de la imagen con el sonido. Surge así el cine sonoro, no exento de temores y recelos empresariales. En México, la historia de la industria cinematográfica es paradójica: se instituye antes de contar con una plataforma sólida. Es bajo la protección del Estado —y su discurso nacionalista— que los empresarios “arriesgan su capital” para el desarrollo del cine. -
25 Cents February 1923
CIRCULATION OF THIS ISSUE OVER 225,000 COPIES ,psyymems_ DIO 25 Cents February 1923 NEWS Over 175 I Ilustrations Edited by H.GERNSBACK `A LOOSE COUPLE THE 100% WIRELESS MAGAZINE CIRCULATION LARGER THAN ANY OTHER PUBLICATION www.americanradiohistory.com CUNNINGHAM TYPE C 300 PATENTED AMPLIFIES AS IT DETECTS Patent Notice Cunningham tubes are covered by pat- enta dated 11 -7 -05. 1- 15 -07, 2 -18 -08 and others issued and pending. Licensed only for amateur or experimental uses in radio communication. Any other use will be an infringement. TYPE C -300 Super - Sensitive DETECTOR $ 500 TYPE C -301 Give Clearest Reception Distortioaless AMPLIFIER Cunningham Tubes used in any standard receiving set tvill enable you and your friends to listen to news reports at breakfast, stock market quotations at lunch, $650 and in the evening sit in your comfortable living -room by the fireside and enjoy the finest music and entertainment of the day. Send 5c for new 32 -page Cunningham Tube catalog, containing detailed instruc- tion for the operation of Cunningham Tubes as well as numerous circuit diagrams and graphic illustrations of tube action. The Cunningham Technical Bureau is at your Service. Address your problems to Dept. R. The trade mark GE Eastern is the guarantee of these quality Home Office:- Representatives: - tubes. Each tube is built to most rigid specifica- 248 First Street 154 West Lake Street tions. San Francisco, Calif. Chicago, Illinois www.americanradiohistory.com Radio News for February, 1923 $ 00 2000Ohm 75o 30000hm Their Deep, Natural- Voiced Pitch Is Rapidly Selling Thousands ACTUALLY-thousands are being snapped up on the strength of their pleasing voice tone and keen sensitive- ness. -
ABSTRACT AWA Review Wireless Comes of Age on the West Coast1
Lee AWA Review Wireless Comes of Age on the West Coast1 !2011 Bartholomew Lee ABSTRACT This is a story primarily about young men and what they accomplished in a remarkable Radio as we know it time, the fi rst two decades of the 20th Century, had many fathers. Cali- and in remarkable places – especially in Cali- fornia enjoyed unique fornia in the Western United States. Guglielmo circumstances that gave (William) Marconi, in his early twenties, elec- rise to independent de- trifi ed the technical world of the late 19th Cen- velopment. Young men tury with his successes using Hertzian electro- explored and advanced magnetic waves to communicate at distance, devices and means of what we now call “radio.” He did this without communication as soon the wired connections to which the world had as they read about ear- turned with enthusiasm earlier in the century. lier advances, especially The telegraph, including undersea cables, and Marconi’s use of wireless the telephone, needed wire, and lots of it. Com- spark systems. The arc munication without such wires, at fi rst wireless as a generator of high telegraphy, opened new vistas. This was par- power continuous wave ticularly so looking out to the world’s oceans. energy for communica- Communication with ships at sea (Marconi’s tions came to California primary initial interest) was now possible. Then, and then the world. Doc a challenge to the expensive cable monopolies Herrold began the fi rst could be mounted. This was so because the new regular broadcasting to a “wireless” meant exactly that: no expensive, known audience around capital-intensive investments in cables, only 1912 in California, using in terminal stations. -
A Guide to Morse Code Proficiency by Gary Hinson, Zl2ifb Version 1 July 2017
A Guide to Morse Code Proficiency by Gary Hinson, ZL2iFB Version 1 July 2017 Contents Introduction Speed Ti ming is ever y thing Pitch Q-codes, abbreviations, punctuation and prosigns Swings and fists Hinson tips Sending better CW Copying CW better Conclusion Reader feedback References Bibliography (other useful resources) Figure 1 ON4IZ Doc's shiny key collection Introduction Properly-formed Morse code is a delight to hear when strong, and copyable by ear even when signals are quite weak. Despite being monotonic and irregular, good Morse has a curiously musical quality, far from monotonous. However, on the air we typically face QRM, QRN, QSB, weak/marginal signals leading to errors and gaps in the copy, confusion, fatigue and frustration. Throw in badly-sent CW such as mis-sent characters, uncorrected errors, spelling mistakes, stray dits and missing dahs, variable timing with seemingly random spacing, plus off-frequency “One of the goals of every transmitters, drift, chirp, ringing filters and so on, and making contact skilled CW operator is to send may become, let’s say, challenging. well. That means good Prompted by a lively discussion around W1RM Pete’s sage comment character formation and this guide offers advice on improving proficiency in Morse code for those character spacing. It makes already using CW (Continuous Wave) on the amateur bands. After⇒ little difference what you use explaining the key issues, you will find tips for both sending and receiving. to do the sending, be it Both aspects are important and can be improved - no matter how good, straight key, bug, keyer, etc.