Infobox video game title MicroVolts collapsible state show image yes image Image MicroVolts Logo.jpg ... vgratings ESRB T vgratings PEGI 12 media requirements MicroVolts is a Massive Multiplayer Online ... for the Personal computer PC . MicroVolts released its first Closed beta Beta Closed Beta ... MicroVolts Closed Beta Starts Today publisher IGN date August 12, 2010 accessdate March 28, 2011 ref ... articles 114 1146647p1.html title MicroVolts Second Closed Beta Starts Today publisher IGN date January ... cite press release url http pc.ign.com articles 115 1154812p1.html title MicroVolts Starts Its Open ... pc.ign.com articles 117 1173560p1.html?RSSwhen2011 06 07 103400&RSSid 1173560 title MicroVolts Official ... editor 27s choice review award microvolts title MMOGames.com Weekly Editor s Choice Review Award MicroVolts author Hargreaves, Cody work MMOGames.com accessdate June 22, 2011 ref Story The game in set ... four original limited edition figures, code named MicroVolts. Naomi, Knox, Pandora and C.H.I.P. were ... World. ref cite web url http www.microvolts.com characters.aspx title MicroVolts Characters ..., Pandora and C.H.I.P. ref cite web url http www.microvolts.com characters.aspx title MicroVolts ... ref Weapons Unique to MicroVolts is the fact that players have access to all 7 types of weapons within ... weapons.aspx title MicroVolts Weapons work MicroVolts.com publisher Rock Hippo Productions ... surveys and tournaments. Gameplay Game Modes There are currently 10 game modes in MicroVolts Team ... MicroVolts Maps & Modes work MicroVolts.com publisher Rock Hippo Production accessdate June 22, 2011 ... and size. ref cite web url http worthplaying.com article 2011 3 7 news 80229 title MicroVolts Open ... www.microvolts.com map modes.aspx title MicroVolts Maps & Modes work MicroVolts.com publisher Rock Hippo .... ref cite web url http www.microvolts.com batteryCharge.aspx title MicroVolts Battery Charge work ... microvolts open beta begins title MicroVolts Open Beta Begins author Mike date March 10, 2011 work MMOCrunch.com ... more details
Image pmeter t.jpg thumb right 238px S Meter of a Ten Tec Orion amateur radio transceiver. An S meter signal strength meter is an indicator often provided on communications receiver s, such as amateur radio receivers or shortwave broadcast receivers. The scale markings are derived from a subjective system of reporting signal strength from S1 to S9 as part of the RST code . The term S unit can be used to refer to the amount of signal strength required to move an S meter indication from one marking to the next. IARU Region 1 Technical Recommendation R.1 The International Amateur Radio Union IARU Region 1 agreed on a technical recommendation for S Meter calibration for High frequency HF and Very high frequency VHF Ultra high frequency UHF transceivers in 1981. ref name iaru standard International Amateur Radio Union Region I 1981 . http www.algonet.se k jarl ssa IARU smeter.html IARU Region 1 Technical Recommendation R.1 . Brighton, England, UK. ref IARU Region 1 Technical Recommendation R.1 defines S9 for the HF bands to be a receiver input power of 73 dBm . This is a level of 50 volt microvolts at the receiver s antenna input assuming the input Electrical impedance impedance of the receiver is 50 Ohm unit ohms . For VHF bands the recommendation defines S9 to be a receiver input power of 93 dBm . This is the equivalent of 5 microvolts in 50 ohms. The recommendation defines a difference of one S unit corresponds to a difference of 6 decibel s dB , equivalent to a voltage ratio of two, or power ratio of four. Signals stronger than S9 are given with an additional dB rating, thus S9 20dB , or, verbally, 20 decibels over S9 . Examples A weak signal with signal strength of S2 corresponds to received power of 115 dBm or 0.40 microvolts in 50 ohms on HF. A strong signal with signal strength of S8 corresponds to received power of 79 dBm or 25 microvolts in 50 ohms on HF. Some signal generators are calibrated in dB above 1uV and have an output in emf. For example to set an HF r ... more details
Orphan date July 2009 Infobox VG collapsible state show image image File Haveonlinelogo.jpg caption aspect ratio resolution developer TOT Thailand TOT GungHo Online Entertainment publisher SK iMedia distributor engine Gamebyro with PhysX version released vgrelease new TWN November 2009 NA TBA genre Third Person Shooter modes Multiplayer platforms Personal computer PC media Download requirements Minimum br CPU 1.4 GHz br RAM 512 MB br GPU GeForce FX 5700 br HDD 600 MB input Mouse Mouse Computing And Keyboard H.A.V.E. Online lang ko , lang ja in the Japanese version, known as MicroVolts in North America and Europe is a Massive Multiplayer Online Massive Multiplayer Online MMO Third person shooter Third Person Shooter TPS cartoon style video game developed by Korean developer, SK iMedia SK imedia . Taiwanese and Thai version are available, with Rock Hippo Productions announcing that they would publish the game for North America and Europe under the name MicroVolts ref cite press release url http pc.ign.com articles 109 1095151p1.html title Rock Hippo Sign Deal with SK imedia for North America and Europe Publishing publisher IGN date June 7, 2010 accessdate July 5, 2011 ref . HAVE online appears to be a clone of Valve s Team Fortress 2. Hosting There has been no word on a South Korea Korean publisher for this game until Gravity Corp announced that it will publish the game in Korea . The company has also announced a Japan Japanese version, although no release date has been set. Chinese video game company , Insrea, has hosted the game in Taiwan. It is currently in open beta . TOT is also publishing the game in Thailand . Rock Hippo Productions announced that it will publish the game in English territories under the name, MicroVolts . References reflist External links http www.have.in.th Official Thai Site http www.microvolts.com Official English Site http www.toywars.jp Official Japanese Site Category 2009 video games Category Video games developed in ... more details
Unreferenced date December 2009 The extracellular field potential is the electrical potential produced by Cell biology cell s, e.g. Neuron nerve or Muscle fiber muscle cell s, outside of the cell. Electrophysiology Electrophysiological studies investigate these potentials using extracellular microelectrode s. In these experiments the extracellular field potential will be detected as an electrical potential whose source and composition is often ambiguous, making its interpretation difficult. Individual nerve cells neuron s may produce Voltage spike spike s seen as peaks of some tens to hundreds of microvolts. Contributions from neighboring neurons may overlap, producing extracellular potentials of up to several millivolts. Spatially integrating over even larger populations of cells, i.e. lumps of nervous tissue nervous or muscle muscular tissue , will produce signals commonly called local field potential s LFP that can be recorded either in the tissue or with suitable equipment at the body surface as, e.g., electroencephalogram EEG , electrocardiogram ECG , or electromyogram EMG . For individual cells, the time course of the extracellular potential theoretically is inversely proportional to the transmembrane current. In practice, however, this is complicated considerably by the very complex Morphology biology morphology of neurons and the overlap of contributions from adjacent cells. See also Local field potential DEFAULTSORT Extracellular Field Potential Category Cell biology Category Electrochemistry Category Electrophysiology Category Membrane biology Category Physical quantities Biology stub ... more details
Noise in audio, recording, and broadcast systems refers to the residual low level sound usually hiss and hum that is heard in quiet periods of a programme. In audio engineering it can refer either to the acoustic noise from loudspeakers, or to the unwanted residual electronic noise signal that gives rise to acoustic noise heard as hiss . This signal noise is commonly measured using A weighting or ITU R 468 noise weighting ITU R 468 weighting Noise is often generated deliberately and used as a test signal . Two types of deliberately generated noise in common use are referred to as white noise , which has a uniform spectral power density at all frequencies, or pink noise which has a power spectral density that falls at 3dB octave with rising frequency. The latter is often more useful in audio testing because it contains constant energy per octave and hence per commonly used 1 3rd octave , rather than a prepondance of energy at high frequencies. In other words it contains energy that is distributed geometrically rather than linearly. See also Noise Noise music Noise music Noise measurement quiescent Noise electronics signal to quantization noise ratio ITU R 468 noise weighting A weighting Weighting filter Equal loudness contour External links http www.sengpielaudio.com calculator noise.htm White noise calculator, thermal noise Voltage in microvolts, conversion to noise level in dBu and dBV and vice versa Noise Category Noise Audio Category Audio electronics ... more details
Input offset voltage math V os math is the differential amplifier differential DC voltage required between the inputs of an amplifier , especially an operational amplifier , to make the output zero 0 volts with respect to ground, or between differential outputs if they exist, for voltage amplifiers . ref cite book title Fundamentals of Analog Circuits last Floyd first Thomas L. coauthors Buchla, David year 1998 publisher Prentice Hall isbn 013836933X url http books.google.com books?id iu4LAAAACAAJ&d ref Typical values are around 1 10mV for cheap commercial grade operational amplifier integrated circuits , but can be a few microvolts if nulled assuming the IC has offset null pins for external adjustment circuits and or if higher quality perhaps laser trimmed devices are used, although this may drift with temperature or age. Chopper amplifiers are used to reduce offset voltages. Input current and input offset current will affect the offset voltage unless low impedance signal sources are used FET input operational amplifiers tend to be better in this respect. References reflist Category Electrical parameters electronics stub de Offset Spannung it Tensione di offset ja ... more details
Image Westoncell Volt.png thumb right alt Woodcut line drawing of H shaped cell in an enclosure with electrical terminals at the top. Drawing from Edward Weston s US Patent 494827 depicting the standard cell. The Weston cell , is a wet cell wet chemical cell that produces a highly stable voltage suitable as a laboratory standard for calibration of voltmeter s. Invented by Edward Weston chemist Edward Weston in 1893, it was adopted as the International Standard for electromotive force EMF between 1911 and 1990. Chemistry The anode is an amalgam chemistry amalgam of cadmium with mercury element mercury with a cathode of pure mercury over which a paste of mercurous sulphate and mercury is placed. The electrolyte is a saturated solution of cadmium sulfate cadmium sulfate octahydrate , and the depolarizer is a paste of mercurous sulfate . As shown in the illustration, the cell is set up in an H shaped glass vessel with the cadmium amalgam in one leg and the pure mercury in the other. Electrical connections to the cadmium amalgam and the mercury are made by platinum wires fused through the lower ends of the legs. big Anode reaction big big Cd big s big big big Cd sup 2 sup aq big big big big 2e sup sup big big Cathode reaction big big Hg sup 2 sup SO sub 4 sub sup 2 sup s big big big big 2e sup sup big big big big 2Hg l big big big big SO sub 4 sub sup 2 sup aq big Reference cells must be applied in such a way that no current is drawn from them. Characteristics The original design was a saturated cadmium cell producing a convenient 1.018638 Volt reference and had the advantage of having a lower temperature coefficient than the previously used Clark cell . ref Robert B. Northrop Introduction to instrumentation and measurements 2nd ed CRC Press, 2005 ISBN 0849337739 page 14 ref The temperature coefficient can be reduced by shifting to an unsaturated design, the predominant type today. However, an unsaturated cell s output decreases by some 80 microvolts per year, which is c ... more details
may not exceed 2400 microvolts per meter divided by the frequency in kilohertz, or approximately 17 microvolts per meter. Countries in which operation is permitted Countries with a known band allocation ... more details
Virtual ground or virtual earth is a node of the circuit that is maintained at a steady reference potential, without being connected directly to the reference potential. In some cases the reference potential is considered to be that of the surface of the earth, and the reference node is called ground or earth as a consequence. The virtual ground concept aids circuit analysis in operational amplifier and other circuits and provides useful practical circuit effects that would be difficult to achieve in other ways. In circuit theory , a Node circuits node may have any value of current or voltage but physical implementations of a virtual ground will have limitations of current handling ability and a non zero Electrical impedance impedance which may have practical side effects. Construction A voltage divider , using two resistors, can be used to create a virtual ground node. If two voltage sources are connected in series with two resistors, it can be shown that the midpoint becomes a virtual ground if math frac V 2 V 1 frac R 2 R 1 math br style clear both Image opampinverting.svg right thumb 280px Op amp inverting amplifier An active virtual ground circuit is sometimes called a rail splitter . Such a circuit uses an op amp or some other circuit element that has gain. Since an operational amplifier has very high open loop gain , the potential difference between its inputs tend to zero when a feedback network is implemented. To achieve a reasonable voltage at the output and thus equilibrium in the system , the output supplies the inverting input via the feedback network with enough voltage to reduce the potential difference between the inputs to microvolts. The non inverting input of the operational amplifier is grounded therefore, its inverting input, although not connected to ground, will assume a similar potential, becoming a virtual ground . Applications Voltage is a differential quantity, which appears between two points. In order to deal only with a voltage an elect ... more details
Interventions infobox Name Electroretinography Image Maximal Response ERG.png Caption Maximal response ERG waveform from a dark adapted eye. ICD10 ICD9 95.21 MeshID D004596 OtherCodes File Electroretinogram.jpg thumb 325px A patient undergoing an electroretinogram Electroretinography measures the electrical responses of various cell types in the retina , including the Photoreceptor cell photoreceptors rod cell rods and cone cell cones , inner retinal cells bipolar cell bipolar and amacrine cell amacrine cells , and the ganglion cell s. Electrode s are usually placed on the cornea and the skin near the human eye eye , although it is possible to record the ERG from skin electrodes. During a recording, the patient s eyes are exposed to standardized stimulus physiology stimuli and the resulting signal is displayed showing the time course of the signal s amplitude voltage . Signals are very small, and typically are measured in microvolts or nanovolts. The ERG is composed of electrical potentials contributed by different cell types within the retina, and the stimulus conditions flash or pattern stimulus, whether a background light is present, and the colors of the stimulus and background can elicit stronger response from certain components. If a flash ERG is performed on a dark adapted eye, the response is primarily from the rod cell rod system . Flash ERGs performed on a light adapted eye will reflect the activity of the cone cell cone system . Sufficiently bright flashes will elicit ERGs containing an a wave initial negative deflection followed by a b wave positive deflection . The leading edge of the a wave is produced by the photoreceptors, while the remainder of the wave is produced by a mixture of cells including photoreceptors, bipolar cell bipolar , amacrine cell amacrine , and Muller cells or Muller glia . ref http webvision.med.utah.edu ERG.html The 20origin 20of 20the 20major 20ERG 20waves Webvision at University of Utah ref The pattern ERG, evoked by an altern ... more details
Infobox laboratory equipment name image URM25d SignalGenerator.jpg alt caption URM 25 Signal Generator c. 1955 acronym other names uses Aligning antique radio equipment notable experiments inventor manufacturer Various, commissioned by U.S. Military model 25D related The AN URM 25 Signal Generator was an electronic vacuum tube radio frequency RF signal generator used during the 1950s and 1960s by the U.S. Military to test electronics electronic equipment. History The AN URM 25 was part of a series of vacuum tube based signal generators built for the U.S. Military in the early Cold War era. Today they are collected and used by vintage amateur radio and antique radio enthusiasts who say they provide reasonably high accuracy and stability for a low cost, with build quality reflecting tough military construction requirements and standards. ref name r 390a.net http www.r 390a.net Pearls URM 25.pdf R 390a.net , URM 25x discussions ref Specifications Image URM25D SignalGenerator FreqMeter.jpg thumb 150px right w Freq. Meter Frequency output ranges from 10 kHz to 50 MHz with amplitude modulation selectable at 400 and 1,000 Hz. RF level from 0.1 microvolts to 100 millivolts or 2 volts is available depending upon termination load. Output impedance is 50,500 ohms. Carrier oscillation is performed by a 6AH6 tube with an additional 6AH6 buffer stage followed by a 6AG7 output amplifier. Amplitude modulation at 400 and 1,000 Hz is provided by a 5814A military 12AU7 oscillator. URM 25x models also contain an internal VTVM Voltmeter Vacuum Tube Voltmeter .28VTVM.29 vacuum tube voltmeter and crystal calibration. The carrier frequency can be set by interpolation using the graduated dial. Additionally, the URM 25 s have a BNC connector for constant 200 mV output that can be connected to a frequency meter to display frequency accurately. A sufficient warm up period is required to ensure the best stability at higher frequencies. The cabinet cover includ ... more details
Image Voltmeter hg.jpg thumb Demonstration voltmeter from a physics class A voltmeter is an instrument used for measuring electrical potential difference between two points in an electric circuit. Analog voltmeters move a pointer across a scale in proportion to the voltage of the circuit digital voltmeters give a numerical display of voltage by use of an analog to digital converter . Voltmeters are made in a wide range of styles. Instruments permanently mounted in a panel are used to monitor generators or other fixed apparatus. Portable instruments, usually equipped to also measure current and resistance in the form of a multimeter , are standard test instruments used in electrical and electronics work. Any measurement that can be converted to a voltage can be displayed on a meter that is suitably calibrated for example, pressure, temperature, flow or level in a chemical process plant. General purpose analog voltmeters may have an accuracy of a few percent of full scale, and are used with voltages from a fraction of a volt to several thousand volts. Digital meters can be made with high accuracy, typically better than 1 . Specially calibrated test instruments have higher accuracies, with laboratory instruments capable of measuring to accuracies of a few parts per million. Meters using amplifier s can measure tiny voltages of microvolts or less. Part of the problem of making an accurate voltmeter is that of calibration to check its accuracy. In laboratories, the Weston Cell is used as a standard voltage for precision work. Precision voltage references are available based on electronic circuits. Analog voltmeter Image Galvanometer diagram.svg thumb A moving coil galvanometer of the d Arsonval type. ul li font face arial color red The red wire carries the current to be measured. font li li font face arial color green The restoring spring is shown in green. font li li N and S are the north and south poles of the magnet. li ul A moving coil galvanometer can be used as a v ... more details
Other uses Gain disambiguation In electronics , gain is a measure of the ability of a electrical network circuit often an amplifier to increase the Power physics power or amplitude of a Signal electrical engineering signal from the input to the output. It is usually defined as the mean ratio of the Signalling telecommunication signal output of a system to the Signalling telecommunication signal input of the same system. It may also be defined on a logarithmic scale, in terms of the decimal logarithm of the same ratio decibel dB gain . A gain greater than one zero dB , that is, amplification, is the defining property of an active component or circuit, while a passive circuit will have a gain of less than one. Thus, the term gain on its own is ambiguous. For example, a gain of five may imply that either the voltage , Electric current current or the Electric power power is increased by a factor of five, although most often this will mean a voltage gain of five for audio and general purpose amplifier s, especially operational amplifiers , but a power gain for radio frequency amplifiers, and for directional aerials will refer to a signal power change compared with a simple dipole. I should check that latter clause in an ARRL handbook Furthermore, the term gain is also applied in systems such as sensor s where the input and output have different units in such cases the gain units must be specified, as in 5 microvolts per photon for the responsivity of a photosensor. The gain of a bipolar transistor normally refers to forward current transfer ratio, either h sub FE sub Beta , the static ratio of I sub c sub divided by I sub b sub at some operating point , or sometimes h sub fe sub the small signal current gain, the slope of the graph of I sub c sub against I sub b sub at a point . In laser physics , gain may refer to the increment of power along the beam propagation in a gain medium , and its dimension is m sup 1 sup inverse meter or 1 meter. Logarithmic units and decibels ... more details
Expand German Ernst Fleischl von Marxow date June 2010 Image Fleischl marxow 2.jpg thumb right Ernst von Fleischl Marxow Ernst von Fleischl Marxow , aka Ernst Fleischl von Marxow 1846 &ndash 1891 was an Austrian physiology physiologist and physician who became known for his important investigations on the electrical activity of nerve s and the brain . He was also a creative inventor of new devices which were widely adopted in clinical medicine and physiological research. Marxow studied medicine in the University of Vienna , Austria . He started his scientific career as a research assistant in the laboratory of Ernst Wilhelm von Br cke 1819 1892 , and later as an assistant, in the same University, to the eminent pathologist Carl Freiherr von Rokitansky Carl von Rokitansky 1804&ndash 1878 . Unfortunately, an accident while he was dissecting a cadaver injured his thumb, ref http thechart.blogs.cnn.com 2011 07 22 sigmund freuds cocaine problem ?hpt hp bn6 ref which became infected and had to be amputated, interrupting his activities in anatomical pathology . Thus, he had to turn to Physiology, and he came back to von Br cke s laboratory in Vienna after studying for a year with Carl Ludwig 1816&ndash 1895 , another famous physiologist at the University of Leipzig , Germany , obtaining his doctoral degree in Medicine in 1874. In the first phase of his career in neurophysiology , Marxow dedicated himself to electrophysiology of nerve s and muscle s, then a research field of increasing prestige, after the pioneering investigations of Emil du Bois Reymond 1818&ndash 1896 , who had discovered the action potential s of axon s. This field highly benefitted from the technical developments occurring in the physics physical sciences , particularly new devices which were invented to work with small electric potential s and electric current currents . Since biological tissue s have extremely low levels of electrical activity in the range of microvolts , neurophysiology s progress ha ... more details
. The voltage created by this effect is of the order of several volt microvolts per kelvin difference. One such combination, copper constantan , has a Seebeck coefficient of 41 microvolts per kelvin ... more details
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