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.7v less than unity for DC operation but unity for AC.

by noticing the polarity of theohmmeter a diode can be checked for continuity and blocking ability However it will not tell you how good or bad the device itself is

BY keeping the multimeter in diode mode and keeping properly the positive and negative terminals of the multimeter. If the diode is good multimeter will show a reading of 0.5 else there will be a short.

A transistor has three leads, called the base, the collector, and the emitter. The voltage of the base (in relation to the ground) determines whether and how much current flows from the collector to the emitter. An NPN transistor can be off, meaning that there is no (or very little) voltage from the base; partly on, meaning that there is some voltage from the base; or saturated, meaning that it is receiving full voltage from the base. A saturated transistor allows the current to flow from the collector to the emitter unopposed; a partly on transistor provides some resistance; and a transistor that is off provides full resistance. A PNP transistor is similar to an NPN transistor except it performs the opposite function: when it is saturated, the current is fully resisted; when there is no voltage from the base, the current is not at all resisted; and when it is partly on there is some resistance.

In sum, a transistor controls the flow between the collector and the emitter based upon the voltage of the base. this is carbage. a transistor is basicaly two diodes back to back base being common TO BOTH DIODES because of inpurity doping on purpose at the depletion region the transistor will control the current flow on the other diode. Once it reaches saturation both diodes conduct therefore current can flow in BOTH DIRECTIONS ACROSS IT.

With today's auto-ranging meters, you might well ask why. Today meters do that for you, and you might see it happening on some of them.

In older meters, analog types in particular, you had to start with a higher range to be sure you didn't peg the meter measuring say, 220 volts when on the 10 volt scale. Lots of meters where toasted this way, their needles bent, or fuses blown by overcurrent. On higher ranges, the meter would deflect slightly, indicating there was voltage there, but not enough to get a accurate reading. So you scale down until hopefully you get a reading somewhere in mid scale, where the most accurate reading can be made.

So the use was to protect the meter from damage, and provide the most accurate reading possible from an analog meter.

Voltage is a defined as a difference in potential. So to measure voltage, you need to look at the difference in potential between two different nodes in a circuit. For example, to know the voltage of a capacitor, you are looking at the difference in potential from one terminal of the capacitor to the other. Even if it is installed in a circuit. It is for this reason, that the measurement is across the circuit, or in parallel with it. One common point of confusion in voltage measurement is the way it is presented. Someone will say, that wire is at 5 volts. The "with reference to" part is often left off. We can say this because most circuits have a direct or implied ground, that all other voltages are referenced to. So the correct thing to say would be "that wire is at 5 volts to ground."

Over Current (Inverse Time) Over current relay function monitors the general balanced overloading and has current/time settings. This is determined by the overall protective discrimination scheme. There advantage over definite time relays is that they can have much shorter tripping times can be obtained without any risk to the protection selection process. These are classified in accordance with there characteristic curves, this indicates the speed of the operation. Based on this they are defined as being inverse, very inverse or extremely inverse. The typical settings for these relays are 0.7-2In (normal or rated generator current) in 1-10 second. Inducing a calibrated test current through the normal load current tests this relay.

Voltage dividers are used in a linear circuit to separate the input voltage into a small portion known as the output voltage. It is commonly used to get a low voltage signal equal to the voltage being measured.

Of or pertaining to an electron or electrons.

Thermal runaway is where the biasing and operating point is such that the temperature causes the gain to increase, which causes the temperature to increase, which causes the gain to increase, in a vicious circle, leading to destruction of the BJT. Proper biasing and gain management can prevent this from occurring.

Keyboard.

Bipolar junction transistors has two junctions base emitter junction, base collector junction. Accordingly there are four different regions of operation in which either of the two junctions are forward biased reverse biased or both. But the BJT can be effectively operated in there different modes according to the external bias voltage applied at each junction. i.e. Transistor in active region, saturation and cutoff. The other region of operation of BJT is called as inverse active region.

The Hubble Space Telescope cost about $1.5 billion to build and place into orbit. From its first pictures, imaging teams realized there was a problem. It turns out the primary mirror was ground incorrectly. The curvature was not to specification, and as an image was analyzed from the center out, the clarity of the image fell off. Poor resolution at the edges of an image made analysis of anything little more than a point object out of the question.

The problem was traced to a null corrector at the mirror manufacturer's site. It was assembled with incorrect spacing in a component, and the null corrector was then used to check the mirror and guide grinding during the shaping of the surface of the reflector. The flaw in the instrument was translated onto the mirror.

A link to the Wikipedia article on the Hubble is provided. So is one to a N.Y. Times article on the glitch.

Incidentally, the Mars Rovers have been spectacularly successful, and continue operating a full six years beyond their expected mission lifespan. The question might be referring to the unsuccessful Mars Climate Orbiter, which was launched in December, 1998.

Any logic gate from which all other logic gate functions can be derived. The two universal gates are NAND and NOR.

A junction is formed when two or more roads, pathways, or circuits meet or intersect. In the context of electrical circuits, a junction occurs where multiple components connect, allowing for the flow of current through various paths. Junctions are essential for directing traffic, both in transportation systems and electrical networks, facilitating movement and connectivity. The design and configuration of a junction can significantly impact efficiency and safety in both domains.

is this coil a single shot solenoid or is it used as a filter i assume you want to know a good value for a varistor to stop voltage spikes from the reverse EMF which is aprox. 4X the input voltage. so i would say to use 2X-3X the input Voltage so 48 or 72 Volt MOV (Metal oxide varistor) You want the varistor to be several volts greater than the peak voltage of the signal across which it is connected. 24 volts is probably the RMS value of the coils voltage. Your varistor must be selected to be greater than the peak voltage. When the voltage exceeds the clamping voltage of the varistor, it conducts current, preventing the voltage from reaching a dangerous level. If the elevated voltage is maintained for too long a time, the varistor will heat to a point where the metals in it melt and fuse together, causing a short. This also poses the posibility of a fire risk, as the current is now conducting heavily through the varistor. This is what often happens to a varistor in a power strip when lightening strikes nearby. It renders the power strip useless. But the connected devices are usually spared.

Any system you design will have an input and an output. The output will connect to the input of another system which will load it, so when you are designing any system you have to consider how loading it will effect the circuit performance.

The Junction Field Effect Transistor (JFET)exhibits characteristics which often make it more suited to a particular application than the bipolar transistor. Some of these applications are:

- High Input Impedance Amplifier

- Low-Noise Amplifier

- Differential Amplifier

- Constant Current Source

- Analogue Switch or Gate

- Voltage Controlled Resistor

Tig, or tungsten inert gas welding used to be known as Heliarc welding when it was first developed in 1941, because helium was then used as the inert gas. As the process has developed and progressed the name was changed to Tungsten Inert Gas welding. Argon or a combination including argon is now more widely used as the inert gas for this process.

There are two conductors were electricity begins and runs through wires which make energy come out of a battery.

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In the center of each cell there is a rod called a cathode. It is usually composed of graphite. Surrounding this cathode there is an electrolytic substance which acts as a medium to conduct electricity. The cathode and electrolytic substance are separated from the outer container by a cardboard tube. This assembly is sealed into a metallic cylinder. In older type batteries this cylinder was made of zinc. This part of the battery is known as the anode. When a load is connected between the cathode (+) and the anode (-) terminals, a chemical reaction takes place between the cathode and the electrolytic material. This chemical reaction generates a 1.5 volt potential between the two terminals.

The MIDI (Musical Instrument Digital Interface) system does not care about the range of frequency of the actual instrument it is playing. It is an event oriented system, much like a player piano, not like a tape recorder, so what is recorded are key down and key up (and other) events, rather than musical waveform events.

A processor, or more commonly a CPU, is an individualized processing device. It may contain multiple cores.

A core is a bank of registers and dedicated cache structure that performs all of a processor's tasks, but is not an entire processor. For example, more multi-core processors have a separate array of logic functions that are not integrated with the core, such as the Memory Controller in AMD Phenom and Phenom II processors. There is one (or two, in the Phenom II) memory controllers total for the processor, reguardless of the number of cores.

Think of a 'core' as a cylinder in an engine. A V8 enginer has 4 'cores', but the engine is the 'processor'. You can have a V12 or a W32 or a V4 or any of another combination, but there's only one processor. However the number of cores can greatly influence the overall power and capability of the processor.

This space is for answering "http://wiki.answers.com/Q/Why_does_voltage_remain_constant_in_the_reverse_breakdown_region_in_a_zener_diode" Why does voltage remain constant in the reverse breakdown region in a zener diode?