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alternating and current
The alternating current power line frequency of 60 Hz was the primary clock rate for the lowest level operations.
Atlas Autocode included a < code >< u > complex </ u ></ code > data type which would support complex numbers, partly because of pressure from the electrical engineering department, as complex numbers are used to represent the behavior of alternating current.
This type of meter responds to both direct and alternating currents ( as opposed to the moving coil ammeter, which works on direct current only ).
As alternating or direct current flows through the coil and induces a magnetic field in both vanes, the vanes repel each other and the moving vane deflects against the restoring force provided by fine helical springs.
This instrument can respond to both alternating and direct current and also indicated true RMS for AC.
For alternating currents, especially at higher frequencies, skin effect causes the current to spread unevenly across the conductor cross-section, with higher density near the surface, thus increasing the apparent resistance.
The abbreviations AC and DC are often used to mean simply alternating and direct, as when they modify current or voltage.
The electric charge flows in a constant direction, distinguishing it from alternating current ( AC ).
In alternating current ( AC, also ac ), the movement of electric charge periodically reverses direction.
Audio and radio signals carried on electrical wires are also examples of alternating current.
He fostered the development of alternating current that made possible the expansion of the electric power industry in the United States, formulating mathematical theories for engineers.
* Steinmetz,, " System of distribution by alternating current.
* Theory and calculation of alternating current phenomena ", with the assistance of Ernst J. Berg, 1897.
This unidirectional behavior is called rectification, and is used to convert alternating current to direct current, including extraction of modulation from radio signals in radio receivers — these diodes are forms of rectifiers.
Rectifiers are constructed from diodes, where they are used to convert alternating current ( AC ) electricity into direct current ( DC ).
When any wire ( or other conducting object such as an antenna ) conducts alternating current, electromagnetic radiation is propagated at the same frequency as the electric current.
In 1887, Nikola Tesla filed a number of patents related to a competing form of power distribution known as alternating current.
Central power stations became economically practical with the development of alternating current power transmission, using power transformers to transmit power at high voltage and with low loss.
In engineering or household applications, current is often described as being either direct current ( DC ) or alternating current ( AC ).
The time-averaged value of an alternating current is zero, but it delivers energy in first one direction, and then the reverse.

alternating and signal
In summary, an AM signal consists of alternating positive and negative peaks of a radio carrier wave, whose amplitude or envelope is proportional to the original audio signal.
Oscillators convert direct current ( DC ) from a power supply to an alternating current signal.
The most common test signal is a series of " RYRYRY " characters, as these form an alternating tone pattern exercising all bits and are easily-recognized.
If the called party's line is available, the exchange sends an intermittent ringing signal ( about 90 volts alternating current ( AC ) in North America and UK and 60 volts in Germany ) to alert the called party to an incoming call.
Rural and other telephones that were not on a common battery exchange had a magneto or hand-cranked generator to produce a high voltage alternating signal to ring the bells of other telephones on the line and to alert the operator.
Unlike the beat frequency oscillator or the induction balance machines which both used a uniform alternating current at a low frequency, the pulse induction machine simply fired a high-voltage pulse of signal into the ground.
This rectifies the alternating current radio wave to a pulsing direct current, whose strength varies with the audio signal.
The detector rectified the alternating current radio signal to a pulsing direct current, which had the audio modulation signal impressed on it, so it could be converted to sound by the earphone, which was connected in series ( or sometimes in parallel ) with the detector.
The signal is compared to a reference signal ( either a quartz crystal or alternating current from the mains ).
Because of the alternating slants, each head will not strongly read the signal recorded by the other head and the stripes can be recorded immediately next to each other, alternating between left slant on one television field and right slant on the next television field.
Additionally, signal shielding was optimised by alternating the live ( hot ) and earthy ( ground ) pins of each pair.
This results in a form of alternating current, but the DCC signal does not follow a sine wave.
Noise cancellation at other locations is more difficult as the three dimensional wavefronts of the unwanted sound and the cancellation signal could match and create alternating zones of constructive and destructive interference.
For two weeks after that, it broadcast a " nightlight " service in the form of a continuously repeating short program about installing digital television converter boxes, alternating between English and Spanish versions, before finally shutting down its analog signal completely.
For small signal alternating current, the definition is simpler:
By adding the steady signal from the sense aerial to the alternating signal from the loop signal as it rotates, there is now only one position as the loop rotates 360 ° at which there is zero current.
Civil defense sirens pulling double duty as a fire siren often can produce an alternating " hi-lo " signal ( similar to a British police car ) as the fire signal, or a slow wail ( typically 3x ) as to not confuse the public with the standard civil defense signals of alert ( steady tone ) and attack ( fast wavering tone ).

alternating and produced
By the 1870s, efficient generators that produced alternating current ( alternators ) were available, and it was found that alternating current could power an induction coil directly, without an interrupter.
For effective degaussing, it is necessary that the magnitude of the alternating magnetic field produced by the degaussing coil decreases smoothly and continuously, rather than sharply switching off or decreasing in steps ; the PTC thermistor accomplishes this naturally as it heats up.
At the tipping point where the oceans became permanently oxygenated, small variations in oxygen production produced pulses of free oxygen in the surface waters, alternating with pulses of iron oxide deposition.
His design idea was to take a basic electrical alternator, which normally operated at speeds that produced alternating current of at most a few hundred hertz, and greatly speed it up in order to create electrical currents at tens of kilohertz.
The alternating magnetic field produced by the current through the coil reacts against the static magnetic field in turn, causing the coil and attached diaphragm to move the air, thus producing sound.
Ribonucleic acid ( RNA ) with two repeating units ( UCUCUCU → UCU CUC UCU ) produced two alternating amino acids.
Sullivan produced a few light operas in the late 1880s and 1890s that were of a more serious nature than most of the G & S series, including The Yeomen of the Guard, Haddon Hall and The Beauty Stone, but Ivanhoe ( which ran for 155 consecutive performances, using alternating casts — a record then and now ) survives as his only real grand opera.
* roll, rushes ( r ), produced by a rapid alternating pattern of teks and kas
The open roll ( or " double-stroke roll ") is played with double strokes alternating between the left and right hands ; the closed roll or multiple-bounce roll is produced by applying slightly more pressure to the fulcrum upon impact which allows for the stick to bounce many times on the drum head.
In 1980, Filmation produced a series of lower-budget Droopy shorts for television as part of a new Tom and Jerry show, with Frank Welker and producer Lou Scheimer alternating as the voice of the hound.
Unknown to any of the team members was the fact that the plane's electrical system used alternating current while the batteries in the tail naturally produced direct current, making the plan futile from the beginning.
The beam passes through the FEL oscillator, a periodic transverse magnetic field produced by an arrangement of magnets with alternating poles within an optical cavity along the beam path.
These devices were used with an alternating current power supply, produced a more regular spark, and could handle more power than conventional static spark gaps.
CFLs are produced for both alternating current ( AC ) and direct current ( DC ) input.
The most common colors for it are white and blue ; however, it is produced in a wide variety of colors, usually alternating colored stripes and puckered white stripes slightly wider than pin stripes.
If direct current is to be produced from single-phase alternating current, then two anodes are used, each connected to the outer ends of a centre-tapped transformer secondary winding.
This allows the conduction of the rectifier to be controlled, for example to delay the instant at which the arc transfers to the anode on the alternating current waveform, thereby giving control of the mean output voltage produced by the rectifier.
In 1911, a large generating station was built in South Boston which produced 25 Hertz alternating current, which could be transmitted long distances at high voltage, to substations which would drop the voltage for use by trains.
Before the development of the transformer and alternating current, direct-current generators produced electricity at " utility voltage " of 120-240 volts, and did not use thousands to millions of volts for transmission.
Later on acting on a suggestion by André-Marie Ampère other results were obtained by introducing a commutator, which produced a pulsating direct current which at this time was preferable to alternating current.
The swimming movement is produced by alternating neural activity between the left and right side of the body, causing it to bend back and forth while creating oscillating movements.

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