by engr. AFAN BK
HISTORY OF ELECTRONIC AND COMPUTER MUSIC
INCLUDING AUTOMATIC INSTRUMENTS AND COMPOSITION MACHINES
2nd century, BC. The Hydraulis was invented by Ktesibios sometime in the second century B.C. Ktesibios, the son of a Greek barber, was fascinated by pneumatics and wrote an early treatise on the use of hydraulic systems for powering mechanical devices. His most famous invention, the Hydraulis, used water to regulate the air pressure inside an organ. A small cistern called the pnigeus was turned upside down and placed inside a barrel of water. A set of pumps forced air into the pnigeus, forming an air reservoir, and that air was channeled up into the organ's action.
Greek Aeolian harp. This may be considered the first automatic instrument. It was named for Aeolus, the Greek god of the wind. The instrument had two bridges over which the strings passed. The instrument was placed in a window where air current would pass, and the strings were activated by the wind current. Rather than being of different lengths, the strings were all the same length and tuned to the same pitch, but because of different string thicknesses, varying pitches could be produced.
5th-6th centuries BC, Pythagorus discovered numerical ratios corresponding to intervals of the musical scale. He associated these ratios with what he called "harmony of the spheres."
890 AD Banu Musa was an organ-building treatise; this was the first written documentation of an automatic instrument.
ca. 995-1050, Guido of Arezzo, a composer, developed an early form of solmization that used a system of mnemonics to learn "unknown songs." The method involved the assignment of alphabetic representations, syllables, to varying joints of the human hand. This system of mnemonics was apparently adapted from a technique used by almanac makers of the time.
1400s The hurdy-gurdy, an organ-grinder-like instrument, was developed.
Isorhythmic motets were developed. These songs made use of patterns of rhythms and pitches to define the composition. Composers like Machaut (14th century), Dufay and Dunstable, (15th century) composed isorhythmic motets. Duration and melody patterns, the talea and the color respectively, were not of identical length. Music was developed by the different permutations of pitch and rhythmic values. So if there were 5 durations and 7 pitches, the pitches were lined up with the durations. Whatever pitches were 'leftover,' got moved to the first duration values. The composer would permute through all pitches and durations before the original pattern would begin again.
Soggetto cavato, a technique of mapping letters of the alphabet into pitches, was developed. This technique was used Josquin's Mass based on the name of Hercules, the Duke of Ferrara. One application of soggetto cavato would involve be to take the vowels in Hercules as follows: e=re=D; u=ut=C (in the solfege system of do, re, mi, fa, etc., ut was the original do syllable); e=re=D. This pattern of vowel-mapping could continue for first and last names, as well as towns and cities.
1500s The first mechanically driven organs were built; water organs called hydraulis were in existence.
Don Nicola Vicentino (1511-1572), Italian composer and theorist, invented Archicembalo, a harpsichord-like instrument with six keyboards and thirty-one steps to an octave.
1600s Athanasius Kircher, described in his book, Musurgia Universalis (1600), a mechanical device that composed music. He used number and arithmetic-number relationships to represent scale, rhythm, and tempo relations, called the Arca Musarithmica.
1624 English philosopher and essayist, Francis Bacon wrote about a scientific utopia in the New Atlantis. He stated "we have sound-houses, where we practice and demonstrate all sounds, and their generation. We have harmonies which you have not, of quarter-sounds, and less slides of sounds."
1641 Blaise Pascal develops the first calculating machine.
1644 The Nouvelle invention de lever, an hydraulic engine produced musical sounds.
1738 Mechanical singing birds and barrel organs were in existence.
The Industrial Revolution flourished. There were attempts to harness steam power to mechanical computation machines
1761 Abbe Delaborde constructed a Clavecin Electrique, Paris, France.
Benjamin Franklin perfected the Glass Harmonica.
Maelzel, inventor of the metronome, and friend of Beethoven invented the Panharmonicon, a keyboard instrument.
1787 Mozart composed the Musikalisches Wurfelspiel (Musical Dice Game). This composition was a series of precomposed measures arranged in random eight-bar phrases to build the composition. Each throw of a pair of dice represented an individual measure, so after eight throws the first phrase was determined.
1796 Carillons, "a sliver of steel, shaped, polished, tempered and then screwed into position so that the projections on a rotating cylinder could pluck at its free extremity," were invented.
1830 Robert Schumann composer the Abegg Variations, op. 1. This composition was named for one of his girlfriends. The principal theme is based on the letters of her name: A-B-E-G-G--this was a later application of a soggetto cavato technique.
1832 Samuel Morse invented the telegraph.
1833-34 Charles Babbage, a British scientist builds the Difference Enginer, a large mechanical computer. In 1834, he imagines the Analytical Engine, a machine that was never realized. Ada Lovelace, daughter of Lord Byron, assisted in the documentation of these fantastic devices.
1835 Schumann composed the Carnaval pieces, op. 9 , twenty-one short pieces for piano. Each piece is based on a different character.
1850 D.D. Parmelee patented the first key-driven adding machine.
1859 David E. Hughes invented a typewriting telegraph utilizing a piano-like keyboard to activate the mechanism.
1863 Hermann Helmholtz wrote the book, On the Sensations of Tone as a Physiological Basis for the Theory of Music. Historically this book was one of the foundations of modern acoustics (this book completed the earlier work of Joseph Sauveur).
1867 Hipps invented the Electromechanical Piano in Neuchatel, Switzerland. He was the director of the telegraph factory there.
1876 Elisha Gray (an inventor of a telephone, along with Bell) invented the Electroharmonic or Electromusical Piano; this instrument transmitted musical tones over wires.
Koenig's Tonametric was invented. This instrument divided four octaves into 670 equal parts--this was an early instrument that made use of microtuning.
1877 Thomas Edison (1847-1931) invented the phonograph. To record, an indentation on a moving strip of paraffin coated paper tape was made by means of a diaphragm with an attached needle. This mechanism eventually lead to a continuously grooved, revolving metal cylinder wrapped in tin foil.
Emile Berliner (1851-1929) developed and patented the cylindrical and disc phonograph system, simultaneously with Edison.
Dorr E. Felti, perfected a calculator with key-driven ratchet wheels which could be moved by one or more teeth at a time.
1880 Alexander Graham Bell (1847-1922) financed his own laboratory in Washington, D.C. Together with Charles S. Tainter, Bell devised and patented several means for transmitting and recording sound.
1895 Julian Carillo's theories of microtones, 96 tone scale, constructed instruments to reproduce divisions as small as a sixteenth tone. He demonstrated his instruments in New York, 1926. The instruments included an Octavina for eighth tones and an Arpa Citera for sixteenth tones. There are several recordings of Carillo's music, especially the string quartets.
1897 E.S. Votey invented the Pianola, an instrument that used a pre-punched, perforated paper roll moved over a capillary bridge. The holes in the paper corresponded to 88 openings in the board.
1898 Valdemar Poulson (1869-1942) patented his "Telegraphone," the first magnetic recording machine.
1906 Thaddeus Cahill invented the Dynamophone, a machine that produced music by an alternating current running dynamos. This was the first additive synthesis device. The Dynamophone was also known as the Telharmonium. The instrument weighed over 200 tons and was designed to transmit sound over telephone wires; however, the wires were too delicate for all the signals. You can sort of consider him the 'Father of Muzak.' The generators produced pure tones of various frequencies and intensity; volume control supplied dynamics. Articles appeared in McClure's Magazine that stated "democracy in music...the musician uses keys and stops to build up voices of flute or clarinet, as the artist uses his brushes for mixing color to obtain a certain hue...it may revolutionize our musical art..."
Lee De Forest (1873-1961) invented the Triode or Audion tube, the first vacuum tube.
1907 Ferruccio Busoni (1866-1924) believed that the current musical system was severely limited, so he stated that instrumental music was dead. His treatise on aesthetics, Sketch of a New Music, discussed the future of music.
1910 The first radio broadcast in NYC (first radio station was built in 1920, also in NYC).
1912 The Italian Futurist movement was founded by Luigi Russolo (1885-1947), a painter, and Filippo Marinetti, a poet. Marinetti wrote the manifesto, Musica Futurista; the Futurist Movement's creed was "To present the musical soul of the masses, of the great factories, of the railways, of the transatlantic liners, of the battleships, of the automobiles and airplanes. To add to the great central themes of the musical poem the domain of the machines and the victorious kingdom of Electricity."
Henry Cowell (1897-1965) introduced tone clusters in piano music. The Banshee and Aeolian Harp are good examples.
1914 The first concert of Futurist music took place. The "art of noises" concert was presented by Marinetti and Russolo in Milan, Italy.
1920 Lev (Leon) Theremin, Russia, invented the Aetherophone (later called the Theremin or Thereminovox). The instrument used 2 vacuum tube oscillators to produce beat notes. Musical sounds were created by "heterodyning" from oscillators which varied pitch. A circuit was altered by changing the distance between 2 elements. The instrument had a radio antenna to control dynamics and a rod sticking out the side that controlled pitch. The performer would move his/her hand along the rod to change pitch, while simultaneously moving his/her other hand in proximity to the antenna. Many composers used this instrument including Varese.
1922 Darius Milhaud (b. 1892) experimented with vocal transformation by phonograph speed changes.
Ottorino Respighi (1879-1936) called for a phonograph recording of nightingales in his Pini di Roma (Pines of Rome).
1926 Jorg Mager built an electronic instrument, the Spharophon. The instrument was first presented at the Donaueschingen Festival (Rimsky-Korsakov composed some experimental works for this instrument). Mager later developed a Partiturophon and a Kaleidophon, both used in theatrical productions. All of these instruments were destroyed in W.W.II.
George Antheil (1900-1959) composed Ballet Mechanique. Antheil was an expatriate American living in France. The work was scored for pianos, xylophones, pianola, doorbells, and an airplane propeller.
1928 Maurice Martenot (b. 1928, France) built the Ondes Martenot (first called the Ondes Musicales). The instrument used the same basic idea as the Theremin, but instead of a radio antenna, it utilized a moveable electrode was used to produce capacitance variants. Performers wore a ring that passed over the keyboard. The instrument used subtractive synthesis. Composers such as Honegger, Messiaen, Milhaud, Dutilleux, and Varese all composed for the instrument.
Friedrich Trautwein (1888-1956, Germany) built the Trautonium. Composers such as Hindemith, Richard Strauss, and Varese wrote for it, although no recordings can be found.
1929 Laurens Hammond (b. 1895, USA), built instruments such as the Hammond Organ, Novachord, Solovox, and reverb devices in the United States. The Hammond Organ used 91 rotary electromagnetic disk generators driven by a synchronous motor with associated gears and tone wheels. It used additive synthesis.
1931 Ruth Crawford Seeger's String Quartet 1931 was composed. This is one of the first works to employ extended serialism, a systematic organization of pitch, rhythm, dynamics, and articulation.
Henry Cowell worked with Leon Theremin to build the Rhythmicon, an instrument which could play metrical combinations of virtually unlimited complexity. With this instrument Cowell composed the Rhythmicana Concerto.
Jorg Mager (Germany) was commissioned to create electronic bell sounds for the Bayreuth production of Parsifal
1935 Allegemeine Elektrizitats Gesellschaft (AEG), built and demonstrated the first Magnetophon (tape recorder).
1937 "War of the Worlds" was directed by Orson Welles. Welles was the first director to use the fade and dissolve technique, first seen in "Citizen Kane." To date, most film directors used blunt splices instead.
Electrochord (the electroacoustic piano) was built.
1938 Novachord built.
1939 Stream of consciousness films came about.
John Cage (1912-1992) began experimenting with indeterminacy. In his composition, Imaginary Landscape No. 1, multiple performers are asked to perform on multiple record players, changing the variable speed settings.
1930s Plastic audio tape was developed.
The Sonorous Cross (an instrument like a Theremin) was built.
1941 Joseph Schillinger wrote the The Schillinger System of Musical Composition. This book offered prescriptions for composition--rhythms, pitches, harmonies, etc. Schilllinger's principal students was George Gershwin and Glenn Miller.
The Ondioline was built.
1944 Percy Grainger and Burnett Cross patented a machine that "freed" music from the constraints of conventional tuning systems and rhythmic inadequacies of human performers. Mechanical invention for composing "Free Music" used eight oscillators and synchronizing equipment in conjunction with photo-sensitive graph paper with the intention that the projected notation could be converted into sound.
1947 Bell Labs developed and produced the solid state transistor.
Milton Babbitt's Three Compositions for Piano serialized all aspects of pitch, rhythm, dynamics, and articulation.
The Solovox and the Clavioline were built.
1948 John Scott Trotter built a composition machine for popular music.
Hugh LeCaine (Canada) built the Electronic Sakbutt, an instrument that actually sounded like a cello.
Pierre Schaeffer (b. 1910), a sound technician working at Radio-diffusion-Television Francaise (RTF) in Paris, produced several short studies in what he called Musique concrete. October, 1948, Schaeffer's early studies were broadcast in a "concert of noises."
Joseph Schillinger wrote The Mathematical Basis of the Arts.
1949 Pierre Schaeffer and engineer Jacques Poullin worked on experiments in sound which they titled "Musique concrete." 1949-50 Schaeffer and Henry (1927-96), along with Poullin composed Symphonie pour un homme seul (Symphony for a Man Alone); the work actually premiered March 18, 1950.
Olivier Messiaen composed his Mode de valeurs et d'intensities (Mode of Durations and Intensities), a piano composition that "established 'scales' not only of pitch but also of duration, loudness, and attack."
The Melochord was invented by H. Bode.
1940s The following instruments were built: the Electronium Pi (actually used by a few German composers, including: Brehme, Degen, and Jacobi), the Multimonica, the Polychord organ, the Tuttivox, the Marshall organ, and other small electric organs.
1950 The Milan Studio was established by Luciano Berio (b. 1925, Italy).
1951-> Clara Rockmore performed on the Theremin in worldwide concerts.
Variations on a Door and a Sigh was composed by Pierre Henry.
The RTF studio was formally established as the Groupe de Musique Concrete, the group opened itself to other composers, including Messiaen and his pupils Pierre Boulez, Karlheinz Stockhausen, and George Barraque. Boulez and Stockhausen left soon after because Schaeffer was not interested in using electronically-generated sounds, but rather wanted to do everything based on recordings.
John Cage's use of indeterminacy culminated with Music of Changes, a work based on the charts from the I Ching, the Chinese book of Oracles.
Structures, Book Ia was one of Pierre Boulez' earliest attempts at employing a small amount of musical material, called cells (whether for use as pitches, durations, dynamics, or attack points), in a highly serialized structure.
1951-53 Eimert and Beyer (b. 1901) produced the first compositions using electronically-generated pitches. The pieces used a mechanized device that produced melodies based on Markov analysis of Stephen Foster tunes.
1952 The Cologne station of Nordwestdeutscher Rundfunk (later Westdeutscher Rundfunk) was founded by Herbert Eimert. He was soon joined by Stockhausen, and they set out to create what they called Elektronische Musik.
John Cage's 4'33" was composed. The composer was trying to liberate the performer and the composer from having to make any conscious decisions, therefore, the only sounds in this piece are those produce by the audience.
1953 Robert Beyer, Werner Meyer-Eppler (b. 1913) and Eimert began experimenting with electronically-generated sounds. Eimert and Meyer-Eppler taught at Darmstadt Summer School (Germany), and gave presentations in Paris as well.
Louis and Bebe Baron set up a private studio in New York, and provided soundtracks for sci-fi films like Forbidden Planet (1956) and Atlantis that used electronic sound scores.
Otto Luening (b. 1900, USA; d. 1996, USA) and Vladimir Ussachevsky (b. 1911, Manchuria; d. 1990, USA) present first concert at the Museum of Modern Art in New York, October 28. The program included Ussachevsky's Sonic Contours (created from piano recordings), and Luening's Fantasy in Space (using flute recordings). Following the concert, they were asked to be on the Today Show with Dave Garroway. Musicians Local 802 raised a fuss because Luening and Ussachevsky were not members of the musicians' union.
1953-4 Karlheinz Stockhausen (b. 1928) used Helmholtz' research as the basis of his Studie I and Studie II. He tried to build increasingly complex synthesized sounds from simple pure frequencies (sine waves).
1954 The Cologne Radio Series "Music of Our Time" (October 19) used only electronically-generated sounds by Stockhausen, Eimert, Pousseur, etc. The pieces used strict serial techniques.
Dripsody was composed by Hugh LeCaine. The single sound source for this concrete piece is a drip of water.
1955 Harry Olson and Belar, both working for RCA, invent the Electronic Music Synthesizer, aka the Olson-Belar Sound Synthesizer. This synth used sawtooth waves that were filtered for other types of timbres. The user programmed the synthesizer with a typewriter-like keyboard that punched commands into a 40-channel paper tape using binary code.
The Columbia-Princeton Studio started, with its beginnings mostly in the living room of Ussachevsky and then the apartment of Luening.
Lejaren Hiller (1924-92) and Leonard Isaacson, from the University of Illinois composed the Illiac String Quartet, the first piece of computer-generated music. The piece was so named because it used a Univac computer and was composed at the University of Illinois.
1955-56 Karlheinz Stockhausen composed Gesang der Junglinge. This work used both concrete recordings of boys' voices and synthesized sounds. The original version was composed for five loudspeakers, but was eventually reduced to four. The text from the Benedicite (O all ye works of the Lord, bless ye the Lord), which appears in Daniel as the canticle sung by the three young Jews consigned to the fiery furnace by Nebuchadnezzar.
1956 Martin Klein and Douglas Bolitho used a Datatron computer called Push-Button Bertha to compose music. This computer was used to compose popular tunes; the tunes were derived from random numerical data that was sieved, or mapped, into a preset tonal scheme.
Tokyo at Japanese Radio, an electronic studio established.
Luening and Ussachevsky wrote incidental music for Orson Welles' King Lear , City Center, New York.
1957 Of Wood and Brass was composed by Luening. Sound sources included trumpets, trombones and marimbas.
Scambi, composed by Henri Pousseur, was created at the Milan Studio, Italy.
Warsaw at Polish Radio, an electronic studio established.
Munich, the Siemens Company, an electronic studio established.
Eindhoven, the Philips Company, an electronic studio established.
David Seville created the Chipmunks, by playing recordings of human voices at double speed. Electronic manipulation was never really used again in rock for about ten years.
1958 Edgard Varese (1883-1965) composed Poeme Electronique for the World's Fair, Brussels. The work was composed for the Philips Pavilion, a building designed by the famous architect, Le Corbusier who was assisted by Iannis Xenakis (who later became well-known as a composer rather than an architect). The work was performed on ca. 425 loudspeakers, and was accompanied by projected images. This was truly one of the first large-scale multimedia productions.
Iannis Xenakis (b.1922) composed Concret PH. This work was also composed for the Brussels World's Fair. It made use of a single sound source: amplified burning charcoal.
Max Mathews, of Bell Laboratories, generated music by computers.
John Cage composed Fontana Mix at the Milan Studio.
London, BBC Radiophonic Workshop, an electronic studio established.
Stockholm, Swedish Radio, an electronic studio established.
The Studio for Experimental Music at the University of Illinois established, directed by Lejaren Hiller.
Pierre Henry leaves the Group de Musique Concrete; they reorganize as the Groupe de Recherches Musicales (GRM)
Gordon Mumma and Robert Ashley founded the Cooperative Studio for Electronic Music, Ann Arbor , MI (University of Michigan).
Luciano Berio composedThema-omaggio a Joyce. The sound source is woman reading from Joyce's Ulysses.
1958-60 Stockhausen composed Kontakte (Contacts) for four-channel tape. There was a second version for piano, percussion and tape.
1958-9 Mauricio Kagel, an Argentinian composer, composed Transicion II, the first piece to call for live tape recorder as part of performance. The work was realized in Cologne. Two musicians perform on a piano, one in the traditional manner, the other playing on the strings and wood. Two other performers use tape recorders so that the work can unites its present of live sounds with its future of pre-recorded materials from later on and its past of recordings made earlier in the performance.
Max Mathews, at Bell Labs, began experimenting with computer programs to create sound material. Mathews and Joan Miller also at Bell Labs, write MUSIC4, the first wide-spread computer sound synthesis program. Versions I through III were experimental versions written in assemble language. Music IV and Music V were written in FORTRAN. MUSIC4 did not allow reentrant instruments (same instrument becoming active again when it is already active), MUSIC5 added this. MUSIC4 required as many different instruments as the thickest chord, while MUSIC5 allowed a score to refer to an instrument as a template, which could then be called upon as many times as was necessary.
The Columbia-Princeton Electronic Music Center was formally established. The group had applied through the Rockefeller Foundation, and suggested the creation of a University Council for Electronic Music. They asked for technical assistants, electronic equipment, space and materials available to other composers free of charge. A grant of $175,000 over five years was made to Columbia and Princeton Universities. In January, 1959, under the direction of Luening and Ussachevsky of Columbia, and Milton Babbitt and Roger Sessions of Princeton, the Center was formally established.
The RCA Mark II synthesizer was built at Columbia-Princeton Electronic Music Center (the original version was built for the artificial creation of human speech). The Mark II contained oscillators and noise generators. The operator had to give the synthesizer instructions on a punched paper roll to control pitch, volume, duration and timbre. The synth used a conventional equal-tempered twelve-note scale.
1960 Composers of more traditional orchestral music began to rebel. Many composers tried to get quasi-electronic sounds out of traditional instruments. Bruno Bartelozzi, wrote new book on extended instrumental techniques.
Morton Subotnick, Pauline Oliveros, and Ramon Sender established the San Francisco Tape Music Center.
John Cage composed Cartridge Music, an indeterminate score for several performers applying gramophone cartridges and contact mics to various objects.
1961 The first electronic music concerts at the Columbia-Princeton Studio were held; the music was received with much hostility from other faculty members.
Varese finally completed Deserts at the Columbia-Princeton Studio.
Fortran-based Music IV was used in the generation of "Bicycle Built for Two" (Mathews).
The production of integrated circuits and specifically VLSI-very large scale integration.
Robert Moog met Herbert Deutsch, and together they created a voltage-controlled synthesizer.
Luciano Berio composed Visage. This radio composition is based on the idea of non-verbal communication. There are many word-like passages, but only one word is spoken during the entire composition (actually heard twice), parole (Italian for 'word'). Cathy Berberian, the composer's wife, was the performer.
The theoretical work, Meta+Hodos, written in 1961 by James Tenney (META Meta+Hodos, 1975 followed).
1962 Bell Labs mass produces transistors, professional amplifiers and suppliers.
PLF 2 was developed by James Tenney. This computer program was used to write Four Stochastic Studies, Ergodos and others.
Iannis Xenakis composed Bohor for eight tracks of sound.
Milton Babbitt composed Ensembles for Synthesizer (1962-64) at the Columbia-Princeton Studio.
At the University of Illinois, Kenneth Gaburo composed Antiphony III, for chorus and tape.
Paul Ketoff built the synket. This synthesizer was built for composer John Eaton and was designed specifically as a live performance instrument.
1963 Lejaren Hiller and Robert Baker composed the Computer Cantata.
Babbitt composed Philomel at the Columbia-Princeton Studio. The story is about Philomel, a woman without a tongue, who is transformed into a nightingale (based on a story by Ovid).
Mario Davidovsky composed Synchronism I for flute and tape. Davidovsky has since written many "synchronism" pieces. These works are all written for live instrument(s) and tape. They explore the synchronizing of events between the live and tape.
1964 The fully developed Moog was released. The modular idea came from the miniaturization of electronics.
Gottfried Michael Koenig used PR-1 (Project 1), a computer program that was written in Fortran and implemented on an IBM 7090 computer. The purpose of the program was to provide data to calculate structure in musical composition; written to perform algorithmic serial operations on incoming data. The second version of PR-1 completed, 1965.
Karlheinz Stockhausen composed Mikrophonie I, a piece that required six musicians to generate. Two performers play a large tam-tam, while two others move microphones around the instrument to pick up different timbres, and the final two performers are controlling electronic processing.
Ilhan Mimaroglu, a Turkish-American composer, wrote Bowery Bum. This is a concrete composition, and used rubber band as single source. It was based on a painting by Dubuffet.
1965 Hi-fi gear is commercially produced.
The first commercially-available Moog.
Varese died.
Karlheinz Stockhausen composed Solo. The composition used a tape recorder with moveable heads to redefine variations in delay between recording and playback, live manipulation during performance.
Karlheinz Stockhausen composed Mikrophonie II for choir, Hammond organ, electronics and tape.
Steve Reich composed It's gonna rain. This is one of the first phase pieces.
1966 The Moog Quartet offered world-wide concerts of (mainly) parlor music.
Herbert Brun composed Non Sequitur VI
Steve Reich composed Come out, another phase piece.
1967 Walter Carlos (later Wendy) composed Switched on Bach using a Moog synthesizer.
Iannis Xenakis wrote Musiques Formelles (Formalized Music). The first discussion of granular synthesis and the clouds and grains of sound is presented in this book.
Leon Kirschner composed String Quartet No. 3, the first piece with electronics to win the Pulitzer Prize.
Kenneth Gaburo composed Antiphony IV, a work for trombone, piccolo, choir and tape.
Morton Subotnick composed Silver Apples of the Moon (title from Yeats), the first work commissioned specifically for the recorded medium.
The Grateful Dead released Anthem of the Sun and Frank Zappa and the Mothers of Invention released Uncle Meat. Both albums made extensive use of electronic manipulation.
1968 Lejaren Hiller and John Cage composed HPSCHD.
Morton Subotnick composed The Wild Bull
Hugh Davies compiled an international catalogue of electronic music.
1969 Terry Riley composed Rainbow in Curved Air
late 1960s The Sal-Mar Construction was built. The instrument was named for composer Salvatore Martirano and designed by him. The Sal-Mar Construction weighed over fifteen hundred pounds and consisted of "analog circuits controlled by internal digital circuits controlled by the composer/performer via a touch-control keyboard with 291 touch-sensitive keys."
Godfrey Winham and Hubert Howe adapted MUSIC IV for the IBM 7094 as MUSIC4B was written in assembly language; MUSIC4BF (a Fortran-language adaptation of MUSIC4B, one version was written by Winham, another was written by Howe).
Music V variants include MUSIC360 and MUSIC11 for the IBM360 and the PDP11 computers, these were written by Barry Vercoe, Roger Hale, and Carl Howe at MIT, respectively.
GROOVE was developed by Mathews and F. Richard Moore at Bell Labs, and was used to control analog synthesizers.
1970 Charles Wuorinen composed "Times Encomium," the first Pulitzer Prize winner for entirely electronic composition.
Charles Dodge composed Earth's Magnetic Field. This is a great example of mapping numerical statistics into musical data.
Steve Reich composed Four Organs.
1972 Pink Floyd's album The Dark Side of the Moon was released; it used ensembles of synthesizers, also used concrete tracks as interludes between tunes.
1973 SAWDUST, a language by Herbert Brun, used functions including: ELEMENT, LINK, MINGLE, MERGER, VARY, and TURN.
1974 The Mellotron was built. The instrument was an early sample player that used tape loops. There were versions that played string sounds or flute sounds, and the instrument was used in movie soundtracks and on recordings.
Clara Rockmore releases Theremin recordings.
1976 Composer Philip Glass collaborated with librettist Robert Wilson on Einstein on the Beach. This was a large-scale multimedia 'opera' in the minimalist style.
1977 The Institut de Recherche et Coordination Acoustique/Musique (IRCAM), Paris, under direction of Pierre Boulez.
Systems Concepts Digital Synthesizer (SCDS), built by Peter Samson for CCRMA, signal generating and processing elements all executing in parallel, and capable of running in real time. There are 256 digital oscillators, 128 signal modifiers (filters, reverb, amplitude scalers), a scratch-pad memory for communicating values between processing elements, and a large memory for reverberation and table storage.
1980 Philip Glass composed Satyagraha, another full scale opera in the minimalist style.
1981 Larry Austin composed Canadian Coastlines, a composition that used a land map of Canada in order to determine textural, rhythmic, and melodic content.
Music V variants: newer developments include Cmusic (by F.R. Moore), so named because it is written entirely in C programming language.
1985 HMSL, Hierarchical Music Specification Language was released. The basic organization of HMSL is a series of data structures called "morphs" (named for the flexible or morphological design of the software). Within the superstructure of these morphs there exist other data substructures named shapes, collections, structures, structures, productions, jobs, players, and actions. These secondary types of morphs are used to control aspects of higher level scheduling and routines.
Interactor, by Morton Subotnick and Mark Coniglio, was designed specifically for live performance and score-following capabilities.
1986 Another Music V variant was release--CSound, by Barry Vercoe of MIT.
Jam Factory written by programmer David Zicarelli. He was trying to create a program that would listen to MIDI input and 'improvise' immediately at some level of proficiency, while allowing (Zicarelli) to improve its ability.
Joel Chadabe, Offenhartz, Widoff, and Zicarelli began work on an algorithmic program that could be used as an improvisation environment. The performer could be seated at the computer and shape data in real time by "a set of scroll bars that changed the parameters of this algorithm, such as the size of the jump from one note to another, the lowest and highest note, etc." The original version was to be named "Maestro," then "RMan" (Random Manager), and finally, "M."
Music Mouse, written by Laurie Speigel, was designed to be a stand-alone performance system. It may be used as a MIDI controller or as a performance station using the Macintosh internal sound. Unlike other programs for the Macintosh environment, Music Mouse was not intended to be used as a recorder/player program. Instead, the program enables the programmer to "play" the computer. Check out the software at: http://www.dorsai.org/~spiegel/ls_programs.html
The Max program was written in the C language and was developed at IRCAM by Miller Puckette. It was later scheduled for distribution by Intelligent Music (the company that also distributed M and Jam Factory), but it was the Opcode company that eventually released it. Miller Puckette's original intention was to build a language that could control IRCAM's 4X synthesizer, and there was no need for the graphical implementation. The graphics were added after a version of Max for Macintosh computer using MIDI was proposed. Since 1989, David Zicarelli has updated and expanded the program for the Macintosh environment.
Dolby SR introduced
R-DAT spec announced
Mackie Designs Inc. founded
Sonic Solutions founded
1987 Apple introduced MacII
first consumer DAT decks available
1988 Steve Reich composed Different Trains for string quartet and tape.
1989 Digidesign introduces Sound Tools
Mackie 1604 debuts
1990 Sony introduces writeable CD
1991 Sony develops MiniDisc
Alesis ADAT introduced
1992 Sony announces multimedia CD-ROM
Emagic founded
Macromedia founded
Spirit by Soundcraft introduced
1994 DVD introduced
1996 first MiniDisc multitracks introduced.
1997 DVD-Audio standard develops
Tuesday, May 26, 2009
22) MAKE YOUR OWN CIRCUIT BOARD
by engr. AFAN BK
This tutorial on circuit board manufacturing is the first in a series of presentations on technical topics that will appear on our web page. Future updates will cover structural analysis of the car and eventually the most of the electrical and mechanical system of Monsoon.
On the Arizona Solar Racing Team, we make all our own circuit boards (at least for prototypes), mostly due to the cost of pro-made boards. However, it is pretty convienent to make them yourself, because you can have a working board in a day. I've been refining the method we use for more than 6 years, and it is very reliable and easy. This method uses laser printed transparencies as a mask on pre-sensitized positive acting circuit boards (from GC Thorsen). Line widths down to less that 12 mil can be made this way (this is good enough for SSOP packages).
Creating the pattern
The first step is to create your circuit pattern, either with a commercial program made for this purpose, or simply with a drawing program like Adobe Illustrator or even something like Microsoft Paint (though making the printed version the correct size may be difficult). I've make boards both ways, but of course, the professional board programs make it much easier.
As a simple example, here is an adaptor so you can use the surface mount package SO-8 in a normal breadboard (the picture is not actual size, but the pdf link will print actual size.
The next step is to print it on a laser printer on a transparency. The key to this technique is to print it twice, to make the dark areas dark enough. So print your pattern again, using the same transparency. Try to align the transparency in the printer exactly the same way both times. A misaligned printout will look like this:
It typically takes me two or three tries to get one that is perfect. I've had good success with the HP LaserJet 6MP and the LaserJet 4MP. The LaserJet 3 almost never let me print twice with good alignment. I would guess any 600dpi laser printer will give good results with some practice. I've found it helps to let the transparency cool before printing on it again.
Aligning the pattern
The next step is to tape your transparency onto a piece of glass. It is important to make sure the right side of the transparency is facing the glass, otherwise your pattern will be mirrored on the board. It is helpful if you print some text on or near the pattern so it is easy to tell which side is which.
In a room that's not too brightly lit, peel off the protective sheet from the circuit board, and align it with your pattern. Place something flat on the back side of the board (like another piece of glass) and clamp it together.
I use large paper binder clips for this (using these has an advantage you'll see later). Double check your alignment and make sure that the pattern is not mirrored. Now you are ready to expose! I keep the whole thing shielded from light until I am outside and ready to go. I usually just put it inside a newspaper or whatever's handy while I get setup outside. It is best to do your exposure around noon, on a cloudless day. If it is partly cloudy, or much earlier or later than say, 11 AM-2 PM, you will have to experiment with the exposure time
Exposing the board
Now expose it to the sun for 1.5 to 2.5 minutes (depending on the light conditions, how thick your glass is, weather, latitude, etc). Fortunately, this process is not too sensitive to exact exposure time. Here in Tucson, we're known for our strong sun and cloudless days. Two minutes works well for me. You can use the levers on the binder clips to get your board aligned perfectly normal to the sun by making the shadows of both clips line up. When you are done exposing, wrap it up, and take it inside for development.
Developing the pattern
The developer for the GC Tech positive acting boards I use is part number 22-226.
This is basically a sodium hydroxide solution (no pun indended), so you should keep it in a tightly closed container when you are not using it to prevent the pH from changing. If you keep the developer in a tightly closed container it will develop a lot of boards and last a long time.
Be sure you read, understand and follow the instructions on both the developer and the etchant solutions before you begin.My instructions here are just a guideline, and are not intended to be a substitute for the label instructions.
Place your exposed board in a plastic tray and pour in enough developer to cover the board. You can speed things up and get a better pattern by gently rocking the tray so fresh solution is washing over your board.In just a few seconds you will see the pattern start to form, and within a couple minutes the exposed areas will be completely washed away. You don't want to overetch, but it is better to be sure the exposed regions are completely rinsed away. You can take the board out and wash it carefully with water then give it a close up inspection to be sure. Be careful not to touch the pattern with your fingers or anything else. It is easy to scratch it and that will cause problems when we etch. When the pattern is finished developing, pour your developer solution back into its container.
Etching the pattern
Before you start etching the board, it is a very good idea to put on some old clothes, or wear an apron and gloves. The board etchant contains ferric chloride which will permanently stain your clothes, or almost anything else it touches, like your countertop.
The etchant works faster if it is warm. You can warm the solution by flowing warm water over the bottle for a few minutes before you use it (be sure to loosen the cap a little). It will still work fine if you don't warm it though. Place your developed board into a plastic tray and pour in the etchant. You will want to gently rock the tray frequently during the etching to speed things up. Depending on how fresh your solution is, how warm it is and how much you agitate the solution, the etching will take from 10 minutes to more than an hour. You will have to check the progress of your board. It is done when the copper is completely gone from the exposed areas. It is helpful to take the board out of the etchant and rinse it with water for better inspection. When the board is done, rinse it thoroughly with plenty of water.
Finishing touches
Now you can start drilling all the holes for your leaded parts. It is easiest to use a dremel for the small holes. The size of the holes can be measured from the actual components, or read off the datasheets for that part. Be careful not to drill larger than it needs to be. This can make soldering the lead to the pad a little difficult.
Tips and tricks
Make your circuit traces as wide as possible. Though I've had success makes traces as narrow as 0.012", there are often pinholes in the traces than can cause open circuits. This is especially true if the board is overexposed. It is important to experiment with exposure time. Too much exposure causes the minor defects in the transparancy to show up in your pattern. Of course, not enough exposure and the exposed areas will not be completly removed by the developer, so the etching will not be able to remove the copper completely. This will cause short circuits at worst, and large leakage currents as best.
I cannot emphasize enough the utility of placing text on your patterns. After your pattern is sandwiched between the glass but before you go outside to expose, LOOK at the pattern and verify it is on correct. It is way to easy to put the wrong side of the transparency towards the board, which would make a mirror image of your pattern.
After you develop your pattern, inspect it carefully with a magnifying glass before etching. If there are scratches or holes in the resist pattern, you can touch it up with a permanent marker. Permanent marker will resist the acid etch remarkably well.
Don't forget to wear clothing protection, as well as eye and hand protection. The board etchant has ruined more than a few of my shirts before I wised up.
After the etching is complete and you have rinsed and dried the board thouroughly, you can double check that all the copper is removed by checking continutity between closely spaced parts of the board with a multimeter. If there is no residual copper still on the board, you will see resistances greater than 30 Mohms (the most I can measure with my meter) between closely spaced points on the board. This is only a fair test if the board is dry.
The green photoresist can be easily removed with acetone (nail polish remover) or less easily with rubbing alcohol. There is no need to buy the expensive resist stripper you may see in stores.
It is useful to make the hole sizes of your component pads the actual size you will be drilling them, or a little smaller. This helps guide the drill bit when you drill so your holes will be better aligned. You'll want to buy a wire drill index with sizes 61-80.
This tutorial on circuit board manufacturing is the first in a series of presentations on technical topics that will appear on our web page. Future updates will cover structural analysis of the car and eventually the most of the electrical and mechanical system of Monsoon.
On the Arizona Solar Racing Team, we make all our own circuit boards (at least for prototypes), mostly due to the cost of pro-made boards. However, it is pretty convienent to make them yourself, because you can have a working board in a day. I've been refining the method we use for more than 6 years, and it is very reliable and easy. This method uses laser printed transparencies as a mask on pre-sensitized positive acting circuit boards (from GC Thorsen). Line widths down to less that 12 mil can be made this way (this is good enough for SSOP packages).
Creating the pattern
The first step is to create your circuit pattern, either with a commercial program made for this purpose, or simply with a drawing program like Adobe Illustrator or even something like Microsoft Paint (though making the printed version the correct size may be difficult). I've make boards both ways, but of course, the professional board programs make it much easier.
As a simple example, here is an adaptor so you can use the surface mount package SO-8 in a normal breadboard (the picture is not actual size, but the pdf link will print actual size.
The next step is to print it on a laser printer on a transparency. The key to this technique is to print it twice, to make the dark areas dark enough. So print your pattern again, using the same transparency. Try to align the transparency in the printer exactly the same way both times. A misaligned printout will look like this:
It typically takes me two or three tries to get one that is perfect. I've had good success with the HP LaserJet 6MP and the LaserJet 4MP. The LaserJet 3 almost never let me print twice with good alignment. I would guess any 600dpi laser printer will give good results with some practice. I've found it helps to let the transparency cool before printing on it again.
Aligning the pattern
The next step is to tape your transparency onto a piece of glass. It is important to make sure the right side of the transparency is facing the glass, otherwise your pattern will be mirrored on the board. It is helpful if you print some text on or near the pattern so it is easy to tell which side is which.
In a room that's not too brightly lit, peel off the protective sheet from the circuit board, and align it with your pattern. Place something flat on the back side of the board (like another piece of glass) and clamp it together.
I use large paper binder clips for this (using these has an advantage you'll see later). Double check your alignment and make sure that the pattern is not mirrored. Now you are ready to expose! I keep the whole thing shielded from light until I am outside and ready to go. I usually just put it inside a newspaper or whatever's handy while I get setup outside. It is best to do your exposure around noon, on a cloudless day. If it is partly cloudy, or much earlier or later than say, 11 AM-2 PM, you will have to experiment with the exposure time
Exposing the board
Now expose it to the sun for 1.5 to 2.5 minutes (depending on the light conditions, how thick your glass is, weather, latitude, etc). Fortunately, this process is not too sensitive to exact exposure time. Here in Tucson, we're known for our strong sun and cloudless days. Two minutes works well for me. You can use the levers on the binder clips to get your board aligned perfectly normal to the sun by making the shadows of both clips line up. When you are done exposing, wrap it up, and take it inside for development.
Developing the pattern
The developer for the GC Tech positive acting boards I use is part number 22-226.
This is basically a sodium hydroxide solution (no pun indended), so you should keep it in a tightly closed container when you are not using it to prevent the pH from changing. If you keep the developer in a tightly closed container it will develop a lot of boards and last a long time.
Be sure you read, understand and follow the instructions on both the developer and the etchant solutions before you begin.My instructions here are just a guideline, and are not intended to be a substitute for the label instructions.
Place your exposed board in a plastic tray and pour in enough developer to cover the board. You can speed things up and get a better pattern by gently rocking the tray so fresh solution is washing over your board.In just a few seconds you will see the pattern start to form, and within a couple minutes the exposed areas will be completely washed away. You don't want to overetch, but it is better to be sure the exposed regions are completely rinsed away. You can take the board out and wash it carefully with water then give it a close up inspection to be sure. Be careful not to touch the pattern with your fingers or anything else. It is easy to scratch it and that will cause problems when we etch. When the pattern is finished developing, pour your developer solution back into its container.
Etching the pattern
Before you start etching the board, it is a very good idea to put on some old clothes, or wear an apron and gloves. The board etchant contains ferric chloride which will permanently stain your clothes, or almost anything else it touches, like your countertop.
The etchant works faster if it is warm. You can warm the solution by flowing warm water over the bottle for a few minutes before you use it (be sure to loosen the cap a little). It will still work fine if you don't warm it though. Place your developed board into a plastic tray and pour in the etchant. You will want to gently rock the tray frequently during the etching to speed things up. Depending on how fresh your solution is, how warm it is and how much you agitate the solution, the etching will take from 10 minutes to more than an hour. You will have to check the progress of your board. It is done when the copper is completely gone from the exposed areas. It is helpful to take the board out of the etchant and rinse it with water for better inspection. When the board is done, rinse it thoroughly with plenty of water.
Finishing touches
Now you can start drilling all the holes for your leaded parts. It is easiest to use a dremel for the small holes. The size of the holes can be measured from the actual components, or read off the datasheets for that part. Be careful not to drill larger than it needs to be. This can make soldering the lead to the pad a little difficult.
Tips and tricks
Make your circuit traces as wide as possible. Though I've had success makes traces as narrow as 0.012", there are often pinholes in the traces than can cause open circuits. This is especially true if the board is overexposed. It is important to experiment with exposure time. Too much exposure causes the minor defects in the transparancy to show up in your pattern. Of course, not enough exposure and the exposed areas will not be completly removed by the developer, so the etching will not be able to remove the copper completely. This will cause short circuits at worst, and large leakage currents as best.
I cannot emphasize enough the utility of placing text on your patterns. After your pattern is sandwiched between the glass but before you go outside to expose, LOOK at the pattern and verify it is on correct. It is way to easy to put the wrong side of the transparency towards the board, which would make a mirror image of your pattern.
After you develop your pattern, inspect it carefully with a magnifying glass before etching. If there are scratches or holes in the resist pattern, you can touch it up with a permanent marker. Permanent marker will resist the acid etch remarkably well.
Don't forget to wear clothing protection, as well as eye and hand protection. The board etchant has ruined more than a few of my shirts before I wised up.
After the etching is complete and you have rinsed and dried the board thouroughly, you can double check that all the copper is removed by checking continutity between closely spaced parts of the board with a multimeter. If there is no residual copper still on the board, you will see resistances greater than 30 Mohms (the most I can measure with my meter) between closely spaced points on the board. This is only a fair test if the board is dry.
The green photoresist can be easily removed with acetone (nail polish remover) or less easily with rubbing alcohol. There is no need to buy the expensive resist stripper you may see in stores.
It is useful to make the hole sizes of your component pads the actual size you will be drilling them, or a little smaller. This helps guide the drill bit when you drill so your holes will be better aligned. You'll want to buy a wire drill index with sizes 61-80.
21) HOW TO CUT COST ON REPAIRING ELECTRONICS ITEMS
by engr. AFAN BK
As you all know that pace of our life has increased and we want everything to be done quickly. In olden days may be time did not play an important role as much as I does today. Everybody is in a hurry to reach somewhere, to see something... to do something. Thanks to our nature of curiosity, we've been and are always finding ways to make things easier for us. This is also making our life better in some ways.
You don't need to go anywhere to see how technology has influenced us. If you enter your kitchen you'll see a number of electronic items around... and which I'm sure some of the husbands may not even know what they are used for or may be how to operate them. So you see, at least one member of the family knows the purpose and knows how to use them. You may not be aware, but this person is dependent on it everyday to make life easy.
Let's take a simple example of a bread toaster. Your wife uses it every day and will be using it for a number of years till one day it stops working. Likewise, there are many more examples like your washing machine, water heater, iron, television set, refrigerator, oven, even your coffee-making machine, etc.
Lisa recently shifted to a new location. She's a single mother busy with her life and career. She's got with her all the possible electronic items that she could think of because they make her life more comfortable and manageable. Everything's new for her so she'll take time to adjust to the new place. She has to find out if there's a bakery nearby, a restaurant, medical shop, hospital, and yes of course she also has to know if there are electricians around... what if on day the heater stops working!
The last one will be difficult to find... you should either be very good at fixing things or should be a technician yourself. But don't be upset about that because we can still work on it. Well, repairing electrical appliances will of course pinch your pocket even if the fault is a small one. If we take care to choose the right product from a right source it will to a certain extent save us from unnecessary repairs.
To explain it further, if you buy a branded product it will cost you more at the beginning but it will be of worth. First of all, the product will be of good quality which will minimize the risk of not working. Also, you'll get free service for certain period which can be a year or two. Even after the period is over they might only charge you a minimum fee for any repair work undertaken. This way you save money and you also know where to contact if the problem persists.
Maintenance is also very important. Always wipe clean the appliance as per the instructions after usage, especially items such as oven, toaster, blender etc. When you keep them in good condition you increase their life and the damage done is less.
You can also follow some simple steps like to unplug the appliance after use, wipe it properly with dry cloth, make sure that the wire doesn't touch water and any electrical appliance is not kept near water. Check if the cords are well connected and use a proper socket for the cord. You can also refer to the appliance brochure when you're going wrong.
Buy Electronic Items Whole Sale; Increase your Profits
Perhaps one of the best ways to buy cheap electronic products is through a wholesaler, be it for business or personal use. However finding a cheap and best electronic items wholesaler is a hard accomplishment for retailers and buyers.
But today, with thousands of wholesalers scouring the Internet for selling products and finding suppliers, consumers and retailers are left with a wide range of options. Purchasing electronic items online like mobile phones, laptops, computers and iPods can be a promising means one can adopt to lower down his expenses.
For making huge profits, a retailer should keep in mind that he ought to have a high turnover. Again, even though the wholesale rates of electronic items are quite cheap compared to its retail price, they are not that cheap as people assume to be. The case may not be like selling a digital camera of retail price $1000 and making a profit of $ 500.
People can think of making little profits by buying an electronic appliance from a wholesaler, only if he adopts a careful strategy of selling that particular electronic gadget. Since there are many retailers providing the same electronic gadget in affordable prices, the competition is fierce and so the profit margin is very less. The best thing a retailer can do is whenever he buys a wholesale electronics, he should think of making a profit of some $30--$50 dollars than trying to reap all the harvest in a single day.
No doubt, buying wholesale electronic products for your business gives you enough scope for making profits, even than you should be careful about certain factors, such as before buying wholesale electronics you should compare and ensure that you are getting a reliable and economic deal, and ensure that even after spending for advertisement you still have a room for profit.
Again in making profit by retailing electronic products one should also be aware of the market trends and enough research is to be done so that he can sell a enough numbers in a day to bring him high profits. Also the pricing and advertising strategies matters a lot in giving better profit in selling electronic items. Anyway, buying electronic goods wholesale for business gives enough scope for making profit, but above all what matters is the marketing strategy and effort.
As you all know that pace of our life has increased and we want everything to be done quickly. In olden days may be time did not play an important role as much as I does today. Everybody is in a hurry to reach somewhere, to see something... to do something. Thanks to our nature of curiosity, we've been and are always finding ways to make things easier for us. This is also making our life better in some ways.
You don't need to go anywhere to see how technology has influenced us. If you enter your kitchen you'll see a number of electronic items around... and which I'm sure some of the husbands may not even know what they are used for or may be how to operate them. So you see, at least one member of the family knows the purpose and knows how to use them. You may not be aware, but this person is dependent on it everyday to make life easy.
Let's take a simple example of a bread toaster. Your wife uses it every day and will be using it for a number of years till one day it stops working. Likewise, there are many more examples like your washing machine, water heater, iron, television set, refrigerator, oven, even your coffee-making machine, etc.
Lisa recently shifted to a new location. She's a single mother busy with her life and career. She's got with her all the possible electronic items that she could think of because they make her life more comfortable and manageable. Everything's new for her so she'll take time to adjust to the new place. She has to find out if there's a bakery nearby, a restaurant, medical shop, hospital, and yes of course she also has to know if there are electricians around... what if on day the heater stops working!
The last one will be difficult to find... you should either be very good at fixing things or should be a technician yourself. But don't be upset about that because we can still work on it. Well, repairing electrical appliances will of course pinch your pocket even if the fault is a small one. If we take care to choose the right product from a right source it will to a certain extent save us from unnecessary repairs.
To explain it further, if you buy a branded product it will cost you more at the beginning but it will be of worth. First of all, the product will be of good quality which will minimize the risk of not working. Also, you'll get free service for certain period which can be a year or two. Even after the period is over they might only charge you a minimum fee for any repair work undertaken. This way you save money and you also know where to contact if the problem persists.
Maintenance is also very important. Always wipe clean the appliance as per the instructions after usage, especially items such as oven, toaster, blender etc. When you keep them in good condition you increase their life and the damage done is less.
You can also follow some simple steps like to unplug the appliance after use, wipe it properly with dry cloth, make sure that the wire doesn't touch water and any electrical appliance is not kept near water. Check if the cords are well connected and use a proper socket for the cord. You can also refer to the appliance brochure when you're going wrong.
Buy Electronic Items Whole Sale; Increase your Profits
Perhaps one of the best ways to buy cheap electronic products is through a wholesaler, be it for business or personal use. However finding a cheap and best electronic items wholesaler is a hard accomplishment for retailers and buyers.
But today, with thousands of wholesalers scouring the Internet for selling products and finding suppliers, consumers and retailers are left with a wide range of options. Purchasing electronic items online like mobile phones, laptops, computers and iPods can be a promising means one can adopt to lower down his expenses.
For making huge profits, a retailer should keep in mind that he ought to have a high turnover. Again, even though the wholesale rates of electronic items are quite cheap compared to its retail price, they are not that cheap as people assume to be. The case may not be like selling a digital camera of retail price $1000 and making a profit of $ 500.
People can think of making little profits by buying an electronic appliance from a wholesaler, only if he adopts a careful strategy of selling that particular electronic gadget. Since there are many retailers providing the same electronic gadget in affordable prices, the competition is fierce and so the profit margin is very less. The best thing a retailer can do is whenever he buys a wholesale electronics, he should think of making a profit of some $30--$50 dollars than trying to reap all the harvest in a single day.
No doubt, buying wholesale electronic products for your business gives you enough scope for making profits, even than you should be careful about certain factors, such as before buying wholesale electronics you should compare and ensure that you are getting a reliable and economic deal, and ensure that even after spending for advertisement you still have a room for profit.
Again in making profit by retailing electronic products one should also be aware of the market trends and enough research is to be done so that he can sell a enough numbers in a day to bring him high profits. Also the pricing and advertising strategies matters a lot in giving better profit in selling electronic items. Anyway, buying electronic goods wholesale for business gives enough scope for making profit, but above all what matters is the marketing strategy and effort.
20) WHY CHOOSE ELECTRONICS ENGINEERING
by engr. AFAN BK
Electronic engineering is a discipline dealing with the behavior and effects of electrons (as in electron tubes and transistors) and with electronic devices, systems, or equipment. The term now also covers a large part of electrical engineering degree courses as studied at most European universities. In the U.S., however, electrical engineering implies all the wide electrical disciplines including electronics.
In many areas, electronic engineering is considered to be at the same level as electrical engineering, requiring that more general programs be called electrical and electronic engineering (many UK and Turkish universities have departments of Electronic and Electrical Engineering). Both define a broad field that encompasses many subfields including those that deal with power, instrumentation engineering, telecommunications, and semiconductor circuit design amongst many others.
Terminology
The name electrical engineering is still used to cover electronic engineering amongst some of the older (notably American) universities and graduates there are called electrical engineers. The distinction between electronic and electrical engineers is becoming more and more distinct. While electrical engineers utilize voltage and current to deliver power, electronic engineers utilize voltage and current to deliver information.
Some people believe the term electrical engineer should be reserved for those having specialised in power and heavy current or high voltage engineering, while others believe that power is just one subset of electrical engineering (and indeed the term power engineering is used in that industry). Again, in recent years there has been a growth of new separate-entry degree courses such as information and communication engineering, often followed by academic departments of similar name.
Most of the European universities now refer electrical engineering as power engineers and make distinction between both Electrical and Electronics Engineering. Beginning in the 1980s, the term computer engineer was often used to refer to electronic or information engineers; however, computer engineering is now considered more a subset of electronic engineering and the term is becoming archaic.
Early electronics
In 1893, Nikola Tesla made the first public demonstration of radio communication. Addressing the Franklin Institute in Philadelphia and the National Electric Light Association, he described and demonstrated in detail the principles of radio communication. In 1896, Guglielmo Marconi went on to develop a practical and widely used radio system. In 1904, John Ambrose Fleming, the first professor of electrical Engineering at University College London, invented the first radio tube, the diode. One year later, in 1906, Robert von Lieben and Lee De Forest independently developed the amplifier tube, called the triode.
Electronics is often considered to have begun when Lee De Forest invented the vacuum tube in 1907 . Within 10 years, his device was used in radio transmitters and receivers as well as systems for long distance telephone calls. Vacuum tubes remained the preferred amplifying device for 40 years, until researchers working for William Shockley at Bell Labs invented the transistor in 1947 . In the following years, transistors made small portable radios, or transistor radios, possible as well as allowing more powerful mainframe computers to be built. Transistors were smaller and required lower voltages than vacuum tubes to work.In the interwar years the subject of electronics was dominated by the worldwide interest in radio and to some extent telephone and telegraph communications. The terms 'wireless' and 'radio' were then used to refer to anything electronic. There were indeed few non-military applications of electronics beyond radio at that time until the advent of television. The subject was not even offered as a separate university degree subject until about 1960.[citation needed]
Prior to the second world war, the subject was commonly known as 'radio engineering' and basically was restricted to aspects of communications and RADAR, commercial radio and early television. At this time, study of radio engineering at universities could only be undertaken as part of a physics degree. Later, in post war years, as consumer devices began to be developed, the field broadened to include modern TV, audio systems, Hi-Fi and latterly computers and microprocessors. In the mid to late 1950s, the term radio engineering gradually gave way to the name electronic engineering, which then became a stand alone university degree subject, usually taught alongside electrical engineering with which it had become associated due to some similarities.
Before the invention of the integrated circuit in 1959, electronic circuits were constructed from discrete components that could be manipulated by hand. These non-integrated circuits consumed much space and power, were prone to failure and were limited in speed although they are still common in simple applications. By contrast, integrated circuits packed a large number — often millions — of tiny electrical components, mainly transistors, into a small chip around the size of a coin.
Modern Electronics
In the field of electronic engineering, engineers design and test circuits that use the electromagnetic properties of electrical components such as resistors, capacitors, inductors, diodes and transistors to achieve a particular functionality. The tuner circuit, which allows the user of a radio to filter out all but a single station, is just one example of such a circuit.
In designing an integrated circuit, electronics engineers first construct circuit schematics that specify the electrical components and describe the interconnections between them. When completed, VLSI engineers convert the schematics into actual layouts, which map the layers of various conductor and semiconductor materials needed to construct the circuit. The conversion from schematics to layouts can be done by software (see electronic design automation) but very often requires human fine-tuning to decrease space and power consumption. Once the layout is complete, it can be sent to a fabrication plant for manufacturing.
Integrated circuits and other electrical components can then be assembled on printed circuit boards to form more complicated circuits. Today, printed circuit boards are found in most electronic devices including televisions, computers and audio players.
Typical electronic engineering undergraduate syllabus
Apart from electromagnetics and network theory, other items in the syllabus are particular to electronics engineering course. Electrical engineering courses have other specialisms such as machines, power generation and distribution. Note that the following list does not include the large quantity of mathematics (maybe apart from the final year) included in each year's study.
Electromagnetics
Elements of vector calculus: divergence and curl; Gauss' and Stokes' theorems, Maxwell's equations: differential and integral forms. Wave equation, Poynting vector. Plane waves: propagation through various media; reflection and refraction; phase and group velocity; skin depth. Transmission lines: characteristic impedance; impedance transformation; Smith chart; impedance matching; pulse excitation. Waveguides: modes in rectangular waveguides; boundary conditions; cut-off frequencies; dispersion relations. Antennas: Dipole antennas; antenna arrays; radiation pattern; reciprocity theorem, antenna gain.
Network analysis
Network graphs: matrices associated with graphs; incidence, fundamental cut set and fundamental circuit matrices. Solution methods: nodal and mesh analysis. Network theorems: superposition, Thevenin and Norton's maximum power transfer, Wye-Delta transformation. Steady state sinusoidal analysis using phasors. Linear constant coefficient differential equations; time domain analysis of simple RLC circuits, Solution of network equations using Laplace transform: frequency domain analysis of RLC circuits. 2-port network parameters: driving point and transfer functions. State equatioons for networks
Electronic devices and circuits
Electronic devices: Energy bands in silicon, intrinsic and extrinsic silicon. Carrier transport in silicon: diffusion current, drift current, mobility, resistivity. Generation and recombination of carriers. p-n junction diode, Zener diode, tunnel diode, BJT, JFET, MOS capacitor, MOSFET, LED, p-I-n and avalanche photo diode, LASERs. Device technology: integrated circuits fabrication process, oxidation, diffusion, ion implantation, photolithography, n-tub, p-tub and twin-tub CMOS process.
Analog circuits: Equivalent circuits (large and small-signal) of diodes, BJTs, JFETs, and MOSFETs. Simple diode circuits, clipping, clamping, rectifier. Biasing and bias stability of transistor and FET amplifiers. Amplifiers: single-and multi-stage, differential, operational, feedback and power. Analysis of amplifiers; frequency response of amplifiers. Simple op-amp circuits. Filters. Sinusoidal oscillators; criterion for oscillation; single-transistor and op-amp configurations. Function generators and wave-shaping circuits, Power supplies.
Digital circuits: of Boolean functions; logic gates digital IC families (DTL, TTL, ECL, MOS, CMOS). Combinational circuits: arithmetic circuits, code converters, multiplexers and decoders. Sequential circuits: latches and flip-flops, counters and shift-registers. Sample and hold circuits, ADCs, DACs. Semiconductor memories. Microprocessor(8085): architecture, programming, memory and I/O interfacing.
Signals and systems
Definitions and properties of Laplace transform, continuous-time and discrete-time Fourier series, continuous-time and discrete-time Fourier Transform, z-transform. Sampling theorems. Linear Time-Invariant (LTI) Systems: definitions and properties; causality, stability, impulse response, convolution, poles and zeros frequency response, group delay, phase delay. Signal transmission through LTI systems. Random signals and noise: probability, random variables, probability density function, autocorrelation, power spectral density, function analogy between vectors & functions.
Control systems
Basic control system components; block diagrammatic description, reduction of block diagrams - Mason's rule. Open loop and closed loop (negative unity feedback) systems and stability analysis of these systems. Signal flow graphs and their use in determining transfer functions of systems; transient and steady state analysis of LTI control systems and frequency response. Analysis of steady-state disturbance rejection and noise sensitivity.
Tools and techniques for LTI control system analysis and design: root loci, Routh-Hurwitz criterion, Bode and Nyquist plots. Control system compensators: elements of lead and lag compensation, elements of Proportional-Integral-Derivative (PID) control. Discretization of continuous time systems using Zero-Order-Hold (ZOH) and ADC's for digital controller implementation. Limitations of digital controllers: aliasing. State variable representation and solution of state equation of LTI control systems. Linearization of Nonlinear dynamical systems with state-space realizations in both frequency and time domains. Fundamental concepts of controllability and observability for MIMO LTI systems. State space realizations: observable and controllable canonical form. Ackerman's formula for state-feedback pole placement. Design of full order and reduced order estimators.
Communications
Analog communication (UTC) systems: amplitude and angle modulation and demodulation systems, spectral analysis of these operations, superheterodyne noise conditions.
Digital communication systems: pulse code modulation (PCM), differential pulse code modulation (DPCM), delta modulation (DM), digital modulation schemes-amplitude, phase and frequency shift keying schemes (ASK, PSK, FSK), matched filter receivers, bandwidth consideration and probability of error calculations for these schemes, GSM, TDMA.
Electronic engineering is a discipline dealing with the behavior and effects of electrons (as in electron tubes and transistors) and with electronic devices, systems, or equipment. The term now also covers a large part of electrical engineering degree courses as studied at most European universities. In the U.S., however, electrical engineering implies all the wide electrical disciplines including electronics.
In many areas, electronic engineering is considered to be at the same level as electrical engineering, requiring that more general programs be called electrical and electronic engineering (many UK and Turkish universities have departments of Electronic and Electrical Engineering). Both define a broad field that encompasses many subfields including those that deal with power, instrumentation engineering, telecommunications, and semiconductor circuit design amongst many others.
Terminology
The name electrical engineering is still used to cover electronic engineering amongst some of the older (notably American) universities and graduates there are called electrical engineers. The distinction between electronic and electrical engineers is becoming more and more distinct. While electrical engineers utilize voltage and current to deliver power, electronic engineers utilize voltage and current to deliver information.
Some people believe the term electrical engineer should be reserved for those having specialised in power and heavy current or high voltage engineering, while others believe that power is just one subset of electrical engineering (and indeed the term power engineering is used in that industry). Again, in recent years there has been a growth of new separate-entry degree courses such as information and communication engineering, often followed by academic departments of similar name.
Most of the European universities now refer electrical engineering as power engineers and make distinction between both Electrical and Electronics Engineering. Beginning in the 1980s, the term computer engineer was often used to refer to electronic or information engineers; however, computer engineering is now considered more a subset of electronic engineering and the term is becoming archaic.
Early electronics
In 1893, Nikola Tesla made the first public demonstration of radio communication. Addressing the Franklin Institute in Philadelphia and the National Electric Light Association, he described and demonstrated in detail the principles of radio communication. In 1896, Guglielmo Marconi went on to develop a practical and widely used radio system. In 1904, John Ambrose Fleming, the first professor of electrical Engineering at University College London, invented the first radio tube, the diode. One year later, in 1906, Robert von Lieben and Lee De Forest independently developed the amplifier tube, called the triode.
Electronics is often considered to have begun when Lee De Forest invented the vacuum tube in 1907 . Within 10 years, his device was used in radio transmitters and receivers as well as systems for long distance telephone calls. Vacuum tubes remained the preferred amplifying device for 40 years, until researchers working for William Shockley at Bell Labs invented the transistor in 1947 . In the following years, transistors made small portable radios, or transistor radios, possible as well as allowing more powerful mainframe computers to be built. Transistors were smaller and required lower voltages than vacuum tubes to work.In the interwar years the subject of electronics was dominated by the worldwide interest in radio and to some extent telephone and telegraph communications. The terms 'wireless' and 'radio' were then used to refer to anything electronic. There were indeed few non-military applications of electronics beyond radio at that time until the advent of television. The subject was not even offered as a separate university degree subject until about 1960.[citation needed]
Prior to the second world war, the subject was commonly known as 'radio engineering' and basically was restricted to aspects of communications and RADAR, commercial radio and early television. At this time, study of radio engineering at universities could only be undertaken as part of a physics degree. Later, in post war years, as consumer devices began to be developed, the field broadened to include modern TV, audio systems, Hi-Fi and latterly computers and microprocessors. In the mid to late 1950s, the term radio engineering gradually gave way to the name electronic engineering, which then became a stand alone university degree subject, usually taught alongside electrical engineering with which it had become associated due to some similarities.
Before the invention of the integrated circuit in 1959, electronic circuits were constructed from discrete components that could be manipulated by hand. These non-integrated circuits consumed much space and power, were prone to failure and were limited in speed although they are still common in simple applications. By contrast, integrated circuits packed a large number — often millions — of tiny electrical components, mainly transistors, into a small chip around the size of a coin.
Modern Electronics
In the field of electronic engineering, engineers design and test circuits that use the electromagnetic properties of electrical components such as resistors, capacitors, inductors, diodes and transistors to achieve a particular functionality. The tuner circuit, which allows the user of a radio to filter out all but a single station, is just one example of such a circuit.
In designing an integrated circuit, electronics engineers first construct circuit schematics that specify the electrical components and describe the interconnections between them. When completed, VLSI engineers convert the schematics into actual layouts, which map the layers of various conductor and semiconductor materials needed to construct the circuit. The conversion from schematics to layouts can be done by software (see electronic design automation) but very often requires human fine-tuning to decrease space and power consumption. Once the layout is complete, it can be sent to a fabrication plant for manufacturing.
Integrated circuits and other electrical components can then be assembled on printed circuit boards to form more complicated circuits. Today, printed circuit boards are found in most electronic devices including televisions, computers and audio players.
Typical electronic engineering undergraduate syllabus
Apart from electromagnetics and network theory, other items in the syllabus are particular to electronics engineering course. Electrical engineering courses have other specialisms such as machines, power generation and distribution. Note that the following list does not include the large quantity of mathematics (maybe apart from the final year) included in each year's study.
Electromagnetics
Elements of vector calculus: divergence and curl; Gauss' and Stokes' theorems, Maxwell's equations: differential and integral forms. Wave equation, Poynting vector. Plane waves: propagation through various media; reflection and refraction; phase and group velocity; skin depth. Transmission lines: characteristic impedance; impedance transformation; Smith chart; impedance matching; pulse excitation. Waveguides: modes in rectangular waveguides; boundary conditions; cut-off frequencies; dispersion relations. Antennas: Dipole antennas; antenna arrays; radiation pattern; reciprocity theorem, antenna gain.
Network analysis
Network graphs: matrices associated with graphs; incidence, fundamental cut set and fundamental circuit matrices. Solution methods: nodal and mesh analysis. Network theorems: superposition, Thevenin and Norton's maximum power transfer, Wye-Delta transformation. Steady state sinusoidal analysis using phasors. Linear constant coefficient differential equations; time domain analysis of simple RLC circuits, Solution of network equations using Laplace transform: frequency domain analysis of RLC circuits. 2-port network parameters: driving point and transfer functions. State equatioons for networks
Electronic devices and circuits
Electronic devices: Energy bands in silicon, intrinsic and extrinsic silicon. Carrier transport in silicon: diffusion current, drift current, mobility, resistivity. Generation and recombination of carriers. p-n junction diode, Zener diode, tunnel diode, BJT, JFET, MOS capacitor, MOSFET, LED, p-I-n and avalanche photo diode, LASERs. Device technology: integrated circuits fabrication process, oxidation, diffusion, ion implantation, photolithography, n-tub, p-tub and twin-tub CMOS process.
Analog circuits: Equivalent circuits (large and small-signal) of diodes, BJTs, JFETs, and MOSFETs. Simple diode circuits, clipping, clamping, rectifier. Biasing and bias stability of transistor and FET amplifiers. Amplifiers: single-and multi-stage, differential, operational, feedback and power. Analysis of amplifiers; frequency response of amplifiers. Simple op-amp circuits. Filters. Sinusoidal oscillators; criterion for oscillation; single-transistor and op-amp configurations. Function generators and wave-shaping circuits, Power supplies.
Digital circuits: of Boolean functions; logic gates digital IC families (DTL, TTL, ECL, MOS, CMOS). Combinational circuits: arithmetic circuits, code converters, multiplexers and decoders. Sequential circuits: latches and flip-flops, counters and shift-registers. Sample and hold circuits, ADCs, DACs. Semiconductor memories. Microprocessor(8085): architecture, programming, memory and I/O interfacing.
Signals and systems
Definitions and properties of Laplace transform, continuous-time and discrete-time Fourier series, continuous-time and discrete-time Fourier Transform, z-transform. Sampling theorems. Linear Time-Invariant (LTI) Systems: definitions and properties; causality, stability, impulse response, convolution, poles and zeros frequency response, group delay, phase delay. Signal transmission through LTI systems. Random signals and noise: probability, random variables, probability density function, autocorrelation, power spectral density, function analogy between vectors & functions.
Control systems
Basic control system components; block diagrammatic description, reduction of block diagrams - Mason's rule. Open loop and closed loop (negative unity feedback) systems and stability analysis of these systems. Signal flow graphs and their use in determining transfer functions of systems; transient and steady state analysis of LTI control systems and frequency response. Analysis of steady-state disturbance rejection and noise sensitivity.
Tools and techniques for LTI control system analysis and design: root loci, Routh-Hurwitz criterion, Bode and Nyquist plots. Control system compensators: elements of lead and lag compensation, elements of Proportional-Integral-Derivative (PID) control. Discretization of continuous time systems using Zero-Order-Hold (ZOH) and ADC's for digital controller implementation. Limitations of digital controllers: aliasing. State variable representation and solution of state equation of LTI control systems. Linearization of Nonlinear dynamical systems with state-space realizations in both frequency and time domains. Fundamental concepts of controllability and observability for MIMO LTI systems. State space realizations: observable and controllable canonical form. Ackerman's formula for state-feedback pole placement. Design of full order and reduced order estimators.
Communications
Analog communication (UTC) systems: amplitude and angle modulation and demodulation systems, spectral analysis of these operations, superheterodyne noise conditions.
Digital communication systems: pulse code modulation (PCM), differential pulse code modulation (DPCM), delta modulation (DM), digital modulation schemes-amplitude, phase and frequency shift keying schemes (ASK, PSK, FSK), matched filter receivers, bandwidth consideration and probability of error calculations for these schemes, GSM, TDMA.
19) LATEST ELECTRONICS PRODUCTS
by engr. AFAN BK
1) Atmel AT42QT1040 4-channel touch controller for mobiles
Atmel has introduced a four channel capacitive touch switch controller for battery products from its Hampshire-based design centre. The IC can be configured using one channel as a proximity sensor, enabling hidden-until-lit user interfaces where the device detects the presence of a finger some distance away from the keypad. Charge-transfer sensing, originally patented by Quantum Research - which Atmel bought last year - uses spread-spectrum modulation to improve immunity from electrical noise.
2) Fairchild Semi FAN 5361 synchronous buck regulator
Fairchild Semiconductor provides designers of cell phones, datacards and netbooks a 6MHz synchronous Buck regulator that delivers high efficiency in a compact and razor-thin footprint. Higher switching frequencies typically lead to lower efficiencies. However, the FAN5361's carefully optimized design mitigates these losses leading to 91% peak efficiency. The device has a light load efficiency at 82% at 1mA load current. By reducing wasted energy, this synchronous DC/DC step-down converter enables longer battery life and less heat dissipation in portable applications that continually strive to accommodate rich functionality. The FAN5361, a 6MHz 600mA Buck regulator, allows the use of tiny 470nH chip inductors and 0402 case size input and output capacitors. .82V.
3) Amplicon Senses 6100 series panel PCs
Amplicon Senses 6100 series of panel PCs comprise industrial panel PCs with 17" or 15" display, touchscreen and IP65 rated front bezels. Prices of the Core 2 Duo Panel PC series start from under £1,000 providing customers with a high quality yet affordable alternative to the expensive PLC vendor models available on the market today. They are suited to applications in a variety of markets, especially building automation systems as a "Supervisor" or "Head End", in kiosks and as SCADA terminals in factory automation and process control applications. The 15" and 17" LCD models are available with dual PCI expansion slots for plug-in cards that provide fieldbus connectivity or without expansion - relying solely on the onboard dual gigabit slots ports for network communication.
4) National Instruments NI 31xx industrial controller
National Instruments' NI 31xx series of industrial controllers provide connectivity to NI test and measurement platforms and a fanless design for long-term deployments. The NI 3110 industrial controller features an Intel SL9JT L2400 1.66 GHz Core Duoprocessor and the NI 3100 industrial controller features an Intel 1.06 GHz Celeron M 423 processor, both of which are configured with the Windows XP operating system. These controllers are ideal for rugged applications that require fanless cooling and a wide range of connectivity to external devices through USB, cabled MXI Express, Ethernet and PCI or PCI Express.
5) RF Solutions FireTrap rugged wireless relay-controller system
RF Solutions is offering an RF remote-activation system allowing up to four 5A-rated relays to be controlled from a range of 200 metres. The radio-receiver/relay-controller is a rugged IP68-rated unit optimised for year-round use with trap-release systems such as clay pigeon launchers, and has settings for momentary, latched and timed relay release. The FireTrap remote-control trap-release system uses narrowband RF technology ensures high reliability by rejecting interference from other radio sources such as mobile phone masts.
6) Tyco Electronics IP67 industrial Ethernet connectors
A IP67-rated ODVA-compliant connector from Tyco Electronics uses a field-installable "common core" connector. With the common core, a single modular connector design can be used across a range of connector configurations to achieve IP20 to IP65/67 sealing. The common core plugs use insulation displacement contact to allow tool-less fast, reliable field termination of either solid or stranded conductors. The connectors meet the requirements of EIA/TIA-568B and IEC 60603-7-1 for Category 5e performance. The plugs are available in 4 positions for operation up to 100 Mb/s and 8 positions for speeds to 1000 Mb/s.
7) AVX 5846 series of board-to-board connectors
The AVX 5846 series of low-profile board-to-board connectors feature a small form factor of 3.0mm stacking height with a 0.4mm pitch contact. The connectors provide increased board space for high-density power components placed between PCBs. The rugged board-to-board connectors are constructed in a pinched contact structure and feature a fully insulated bottom plate that protects the contacts, making the device highly resistant to vibration, drop shock, and short-circuits in respect to printed tracks on the PCB.
8) Toshiba TLP3782 and TLP378 high noise immunity 800V couplers
Toshiba Electronics Europe has two miniature photocouplers that are ideal for office equipment, home appliances, solid state relays and other applications demanding high impulse noise immunity. The TLP3782 and TLP378 zero-crossing devices provide minimum isolation voltages of 5000Vrms between sensitive logic and AC currents. Each device is rated for typical impulse noise durability of 1500V. The photocouplers consist of a GaAlAs LED that is optically coupled to a triac output photocoupler and can be used to control current in both forward and reverse directions. Minimum peak off-state voltage is rated at 800V.
9) Aerco AE363 ActiveTouch key pads
Aerco has been appointed a distributor for ITW Switches and now supplies ActiveMetal keypads. The raised profile, solid-metal, vandal-proof keypads use ActiveTouch technology to provide the highest possible standards in terms of ruggedness, weather-resistance, reliability and vandal-resistance. Designed for indoor and outdoor access control, kiosks, point of sale terminals, ATM machines and security alarms, ActiveMetal keypads will find applications in the industrial and commercial sectors, medical establishments and the security and prison service.
10) Tektronix waveform monitor enhancements
Tektronix has added enhancements to its waveform monitor and rasterizer product family which are intended to allow broadcasters, network operators, and content providers to detect and diagnose problems in video and audio quality and detect ancillary data problems. The instruments offer simultaneous decoding and monitoring of CEA-708 and CEA-608 Closed Captioning data, meeting the latest FCC requirements. The units now also support Active Format Description (AFD) and CGMS-A / Broadcast Flag data decoding and monitoring. For multi-channel audio, new Dolby E Guard Band monitoring provides user selectable thresholds and an intuitive bar meter display on the audio display so that operators can spot Dolby E audio problems.
1) Atmel AT42QT1040 4-channel touch controller for mobiles
Atmel has introduced a four channel capacitive touch switch controller for battery products from its Hampshire-based design centre. The IC can be configured using one channel as a proximity sensor, enabling hidden-until-lit user interfaces where the device detects the presence of a finger some distance away from the keypad. Charge-transfer sensing, originally patented by Quantum Research - which Atmel bought last year - uses spread-spectrum modulation to improve immunity from electrical noise.
2) Fairchild Semi FAN 5361 synchronous buck regulator
Fairchild Semiconductor provides designers of cell phones, datacards and netbooks a 6MHz synchronous Buck regulator that delivers high efficiency in a compact and razor-thin footprint. Higher switching frequencies typically lead to lower efficiencies. However, the FAN5361's carefully optimized design mitigates these losses leading to 91% peak efficiency. The device has a light load efficiency at 82% at 1mA load current. By reducing wasted energy, this synchronous DC/DC step-down converter enables longer battery life and less heat dissipation in portable applications that continually strive to accommodate rich functionality. The FAN5361, a 6MHz 600mA Buck regulator, allows the use of tiny 470nH chip inductors and 0402 case size input and output capacitors. .82V.
3) Amplicon Senses 6100 series panel PCs
Amplicon Senses 6100 series of panel PCs comprise industrial panel PCs with 17" or 15" display, touchscreen and IP65 rated front bezels. Prices of the Core 2 Duo Panel PC series start from under £1,000 providing customers with a high quality yet affordable alternative to the expensive PLC vendor models available on the market today. They are suited to applications in a variety of markets, especially building automation systems as a "Supervisor" or "Head End", in kiosks and as SCADA terminals in factory automation and process control applications. The 15" and 17" LCD models are available with dual PCI expansion slots for plug-in cards that provide fieldbus connectivity or without expansion - relying solely on the onboard dual gigabit slots ports for network communication.
4) National Instruments NI 31xx industrial controller
National Instruments' NI 31xx series of industrial controllers provide connectivity to NI test and measurement platforms and a fanless design for long-term deployments. The NI 3110 industrial controller features an Intel SL9JT L2400 1.66 GHz Core Duoprocessor and the NI 3100 industrial controller features an Intel 1.06 GHz Celeron M 423 processor, both of which are configured with the Windows XP operating system. These controllers are ideal for rugged applications that require fanless cooling and a wide range of connectivity to external devices through USB, cabled MXI Express, Ethernet and PCI or PCI Express.
5) RF Solutions FireTrap rugged wireless relay-controller system
RF Solutions is offering an RF remote-activation system allowing up to four 5A-rated relays to be controlled from a range of 200 metres. The radio-receiver/relay-controller is a rugged IP68-rated unit optimised for year-round use with trap-release systems such as clay pigeon launchers, and has settings for momentary, latched and timed relay release. The FireTrap remote-control trap-release system uses narrowband RF technology ensures high reliability by rejecting interference from other radio sources such as mobile phone masts.
6) Tyco Electronics IP67 industrial Ethernet connectors
A IP67-rated ODVA-compliant connector from Tyco Electronics uses a field-installable "common core" connector. With the common core, a single modular connector design can be used across a range of connector configurations to achieve IP20 to IP65/67 sealing. The common core plugs use insulation displacement contact to allow tool-less fast, reliable field termination of either solid or stranded conductors. The connectors meet the requirements of EIA/TIA-568B and IEC 60603-7-1 for Category 5e performance. The plugs are available in 4 positions for operation up to 100 Mb/s and 8 positions for speeds to 1000 Mb/s.
7) AVX 5846 series of board-to-board connectors
The AVX 5846 series of low-profile board-to-board connectors feature a small form factor of 3.0mm stacking height with a 0.4mm pitch contact. The connectors provide increased board space for high-density power components placed between PCBs. The rugged board-to-board connectors are constructed in a pinched contact structure and feature a fully insulated bottom plate that protects the contacts, making the device highly resistant to vibration, drop shock, and short-circuits in respect to printed tracks on the PCB.
8) Toshiba TLP3782 and TLP378 high noise immunity 800V couplers
Toshiba Electronics Europe has two miniature photocouplers that are ideal for office equipment, home appliances, solid state relays and other applications demanding high impulse noise immunity. The TLP3782 and TLP378 zero-crossing devices provide minimum isolation voltages of 5000Vrms between sensitive logic and AC currents. Each device is rated for typical impulse noise durability of 1500V. The photocouplers consist of a GaAlAs LED that is optically coupled to a triac output photocoupler and can be used to control current in both forward and reverse directions. Minimum peak off-state voltage is rated at 800V.
9) Aerco AE363 ActiveTouch key pads
Aerco has been appointed a distributor for ITW Switches and now supplies ActiveMetal keypads. The raised profile, solid-metal, vandal-proof keypads use ActiveTouch technology to provide the highest possible standards in terms of ruggedness, weather-resistance, reliability and vandal-resistance. Designed for indoor and outdoor access control, kiosks, point of sale terminals, ATM machines and security alarms, ActiveMetal keypads will find applications in the industrial and commercial sectors, medical establishments and the security and prison service.
10) Tektronix waveform monitor enhancements
Tektronix has added enhancements to its waveform monitor and rasterizer product family which are intended to allow broadcasters, network operators, and content providers to detect and diagnose problems in video and audio quality and detect ancillary data problems. The instruments offer simultaneous decoding and monitoring of CEA-708 and CEA-608 Closed Captioning data, meeting the latest FCC requirements. The units now also support Active Format Description (AFD) and CGMS-A / Broadcast Flag data decoding and monitoring. For multi-channel audio, new Dolby E Guard Band monitoring provides user selectable thresholds and an intuitive bar meter display on the audio display so that operators can spot Dolby E audio problems.
18) HOW TO MAKE A SIMPLE INVERTER FOR FLORESCENT LAMPS
by engr. AFAN BK
This inverter is very easy to construct, reliable, and even powerful enough to light up a 15W florescent tube (if you cool your transistor well). The only hard-to-find piece of this baby is the so-called yellow inverter transformer. It's a miniature high frequency transformer that has a 25mm x 20mm x 5mm ferrite core, 30 turns of primary, 15 turns of feedback, and 250 turns of secondary all concentric, wound on plastic frame than wrapped with a 'yellow' adhesive tape. If you can't find it in your local electronic shops then search for old portable rechargeble florescent lanterns since they have at least one yellow inverter. Of course you can wind a handmade transformer which would do the same but it is a very difficult task when you don't have an original to inspire and it will still need an appropriate ferrite core.
This is a single transistor oscillator circuit. Current passed through primary winding inducts a magnetic field to the core and the core gives the energy back to the feedback winding with a delay determined by the core material and windings. System then oscillates continuously on a frequency depending on this timing. You cannot use 2SD882 with voltages over 4.5 volts. It is only needed if you are going to feed the circuit with only 4.5 volts. Equivalent transistors may not work as good as 2SD882 (NEC Electronics, Japan). Characteristics are below :
Bipolar NPN transistor : 2SD882 (or D882 as labeled)
Casing : TO126
Max. collector current : 3 Amperes
Max. total power : 10 Watts, while case is at 25 degrees Celsius
Transition frequency : 45 MHz
Max. collector capacity : 45 pF
hFE (current gain) : 160 at 1 Ampere (typical value)
Bipolar NPN transistor : BD243C
Casing : TO220
Max. collector current : 6 Amperes
Max. total power : 65 Watts, while case is at 25 degrees Celsius
Transition frequency : 3 MHz
hFE (current gain) : 30 at 300mA (minimum value)
In case you decided to build your own transformer, here are the instructions to create one:
First of all, you have to find a ferrite core transformer frame. It may be found in discarded rechargeable fluorescent lanterns (in this case it will be probably ready to use), fluorescent tube lights build to use in cars, at electronics stores, and in the energy saver lamps.
Following work describes the process to gain a ferrite core transformer from a dead energy saver lamp and give it a new life
as the heart of the inverter. Please note that these lamps are in various sizes under various brands and it's important to get a transformer which is near or equal in size given above (25mm x 20mm x 5mm). Otherwise it may be difficult to fit the windings on it and performance may noticeably degraded.
Open the lamp and take out the PCB. Locate the ferrite core transformer and unsolder it. Detach the core parts and unwind
the wires on the frame. Now you have an empty frame and two E shaped core parts.
performance and easy fitting. Place primary and feedback windings on opposite sides of the frame. Primary winding will run over on feedback in this case but it is not so important. It also isn't important in which direction the windings are made, you just have to change two wires' places to make circuit work, But for a problemless first run and make the transformer to fit on the PCB right, follow these instructions:
Number the four slot as 1-2-3-4. Now take the care: start with winding the feedback, put wire at slot 2 then wind on clockwise. When 18 cycles completed, stop winding and put the end of the wire in slot 3. Start on slot 4 for primary, wind 25-30 cycles clockwise and end in slot 1. Now the polarity of the leads are correct for the layout of the printed circuit board design. If you make a mistake at this point or just confused, it does not matter at all. Allow wires came out 2cm or more long from the frame, then you will be able to swap feedback (or primary) connections in case of wrong phase polarity. There should be thin spacers made out of adhesive tapes, between the contact points of core parts. If you got your ferrite core with this spacers on it, do not remove them. If there isn't any spacers, you can use very thin adhesive tape to make them. If you don't use any, performance of the transformer will be degraded. You should manually move two core parts relative to each other in order to find the best operating point which can be determined from the brightness of the lamp.
After the PCB has created and components are soldered on, carefully check your work for possible short circuits before applying power. As a drawback of simplicity, circuit doesn't have any current limiters to survive any. Be aware that there will be more than a few hundreds of open circuit voltage on the secondary outputs, thus take care of the solder points.
Inverter in operation
Since the current passed through tube determined by the input voltage of the inverter, do not overlight tubes that you don't want to destroy. For example, the energy saver lamp's tube lighted with 12Volts above becomes much brighter than it's original 220Volts operation. Although looks great, it becomes hot and starts to blacken inside. So adjust the input voltage to light up your tubes at a usable brightness to extend lifetime.
It's certainly possible to light up ultraviolet (blacklight) tubes for fancy experiments and decorations. F8T5 tubes can be easily lighted up with theinverter. Just take this advice: as the tubes get old, they draw more current from the inverter. So always use a tube that lights up well and consumpts less current
This inverter is very easy to construct, reliable, and even powerful enough to light up a 15W florescent tube (if you cool your transistor well). The only hard-to-find piece of this baby is the so-called yellow inverter transformer. It's a miniature high frequency transformer that has a 25mm x 20mm x 5mm ferrite core, 30 turns of primary, 15 turns of feedback, and 250 turns of secondary all concentric, wound on plastic frame than wrapped with a 'yellow' adhesive tape. If you can't find it in your local electronic shops then search for old portable rechargeble florescent lanterns since they have at least one yellow inverter. Of course you can wind a handmade transformer which would do the same but it is a very difficult task when you don't have an original to inspire and it will still need an appropriate ferrite core.
This is a single transistor oscillator circuit. Current passed through primary winding inducts a magnetic field to the core and the core gives the energy back to the feedback winding with a delay determined by the core material and windings. System then oscillates continuously on a frequency depending on this timing. You cannot use 2SD882 with voltages over 4.5 volts. It is only needed if you are going to feed the circuit with only 4.5 volts. Equivalent transistors may not work as good as 2SD882 (NEC Electronics, Japan). Characteristics are below :
Bipolar NPN transistor : 2SD882 (or D882 as labeled)
Casing : TO126
Max. collector current : 3 Amperes
Max. total power : 10 Watts, while case is at 25 degrees Celsius
Transition frequency : 45 MHz
Max. collector capacity : 45 pF
hFE (current gain) : 160 at 1 Ampere (typical value)
Bipolar NPN transistor : BD243C
Casing : TO220
Max. collector current : 6 Amperes
Max. total power : 65 Watts, while case is at 25 degrees Celsius
Transition frequency : 3 MHz
hFE (current gain) : 30 at 300mA (minimum value)
In case you decided to build your own transformer, here are the instructions to create one:
First of all, you have to find a ferrite core transformer frame. It may be found in discarded rechargeable fluorescent lanterns (in this case it will be probably ready to use), fluorescent tube lights build to use in cars, at electronics stores, and in the energy saver lamps.
Following work describes the process to gain a ferrite core transformer from a dead energy saver lamp and give it a new life
as the heart of the inverter. Please note that these lamps are in various sizes under various brands and it's important to get a transformer which is near or equal in size given above (25mm x 20mm x 5mm). Otherwise it may be difficult to fit the windings on it and performance may noticeably degraded.
Open the lamp and take out the PCB. Locate the ferrite core transformer and unsolder it. Detach the core parts and unwind
the wires on the frame. Now you have an empty frame and two E shaped core parts.
performance and easy fitting. Place primary and feedback windings on opposite sides of the frame. Primary winding will run over on feedback in this case but it is not so important. It also isn't important in which direction the windings are made, you just have to change two wires' places to make circuit work, But for a problemless first run and make the transformer to fit on the PCB right, follow these instructions:
Number the four slot as 1-2-3-4. Now take the care: start with winding the feedback, put wire at slot 2 then wind on clockwise. When 18 cycles completed, stop winding and put the end of the wire in slot 3. Start on slot 4 for primary, wind 25-30 cycles clockwise and end in slot 1. Now the polarity of the leads are correct for the layout of the printed circuit board design. If you make a mistake at this point or just confused, it does not matter at all. Allow wires came out 2cm or more long from the frame, then you will be able to swap feedback (or primary) connections in case of wrong phase polarity. There should be thin spacers made out of adhesive tapes, between the contact points of core parts. If you got your ferrite core with this spacers on it, do not remove them. If there isn't any spacers, you can use very thin adhesive tape to make them. If you don't use any, performance of the transformer will be degraded. You should manually move two core parts relative to each other in order to find the best operating point which can be determined from the brightness of the lamp.
After the PCB has created and components are soldered on, carefully check your work for possible short circuits before applying power. As a drawback of simplicity, circuit doesn't have any current limiters to survive any. Be aware that there will be more than a few hundreds of open circuit voltage on the secondary outputs, thus take care of the solder points.
Inverter in operation
Since the current passed through tube determined by the input voltage of the inverter, do not overlight tubes that you don't want to destroy. For example, the energy saver lamp's tube lighted with 12Volts above becomes much brighter than it's original 220Volts operation. Although looks great, it becomes hot and starts to blacken inside. So adjust the input voltage to light up your tubes at a usable brightness to extend lifetime.
It's certainly possible to light up ultraviolet (blacklight) tubes for fancy experiments and decorations. F8T5 tubes can be easily lighted up with theinverter. Just take this advice: as the tubes get old, they draw more current from the inverter. So always use a tube that lights up well and consumpts less current
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