this queston  belongs to the subject power electronics
213416
A thyristor is a semiconductor made of 4 levels of semiconductor material.Monoestable one state biestable two state Astable has no stable state. So a tiristor is bistable
169731
visit \nwww.ciit.edu.pk \n\ngud info for BS electronics
85198
power=voltage^2/resistance\nhigher power means lower resistance.
449877
if your dealing with simple power supplies that supply DC electronics is pretty simply to get them to run on 50Hz. the first pic is a 60Hz supply....\nhttp://aycu34.webshots.com/image/5353/2000360261420977563_rs.jpg\nall you need to do is add some more capacitance to prevent the ripple voltage from dropping...\nhttp://aycu26.webshots.com/image/4785/2000376600521609993_rs.jpg\n\nbut from the sounds of it, you are dealing with AC electronics. Im sorry I do not have an answer for that.
382455
http://www.rselectronics.com
202627
this might prove to be useful:\nhttp://islab.oregonstate.edu/koc/ece575/02Project/Mor/
20757
By Lance Ulanoff  \nImagine a world where all your portable devices can be charged and powered simply by placing them on a desktop. Chip manufacturer MobileWise has gone well beyond imagining such a world and this week unveiled "a conductive solution" that it believes can make it all possible.\n\nDuring a mid-day press conference in chilly New York City, MobileWise showed off a handful of functioning prototype powerbases and retrofitted mobile devices that all use the company's new MobileWise chipset and enable "Wire-Free" electric power. One chip, the tiny Adapter Controller, goes inside the mobile device and the other, the Contact Controller, gets built into the power base station. These power bases, which were shown in a wide variety of shapes, sizes and colors, are each covered in an array of gold-plated contacts. The retrofitted mobile devices also have a pair of contracts. With properly configured handheld devices, the bases can, according to company CEO Andy Goren, change any flat surface into a charging/power station.\n\n \n \n \nThe patent-pending technology behind the MobileWise is, on the surface, quite simple. The adapter chip inside the handheld device will, when placed on a base station, receive a very small electrical signal and message from the base controller chip that will power up the adapter chip. The base controller chip will sense for polarity. If there is none (say you place your hand on the base) then it does nothing. If it does find polarity and then a signal from the adapter chip, it will then read information about the voltage level necessary to run the mobile device and begin charging and powering it. Because of the array of contacts—from dozens to hundreds, depending on base size—there's no need to place the device in a special spot or position on the base. In fact, during the demonstration we saw the bases accept multiple devices, charging and powering them all at once.\n\nThe solution is not actually entirely "wire free", however. The base station is plugged into an AC adapter and can deliver up to 30V DC to an individual device. It's also, according to Goren, completely safe, and if any charge were delivered to a person, it would be at the level of a low-voltage battery, virtually imperceptible to humans and certainly not harmful, he added. The final base units will also, he said, be waterproof and protected from electrostatic charges. \n \n \n\n\nDespite calls for MobileWise to manufacture the bases, Goren said the company plans instead on delivering the chipsets to partners who will likely build the adapter chip and proper contacts into their products and OEM the power base manufacturing to another company. MobileWise showed a variety of colors and form factors for the bases.\n\n \n \n \nAcer has already partnered with MobileWise and, according to Goren, may ship a MobileWise-enabled notebook by Q1 of next year. But MobileWise has, it seems, even more intriguing plans on the horizon. The company is already in discussion with a couple of major office furniture manufacturers to build the power array bases and controller chips into furniture. Apparently, these bases are for more than just mobile devices. Properly-equipped televisions, lamps and more could be powered by the bases—Goren even had an HDTV that worked with one of the larger ones. Later next year, MobileWise expects to add data handshake capabilities to the chipset, allowing, once the signal is split, data delivery over the same contacts.\n\nWhile no shipping units currently exist, MobileWise said the adapter chips run roughly $1.25 a piece adding, it said, just a few dollars in manufacturing costs to mobile devices and the base stations could, in units of 100,000 cost roughly $11 to manufacturers. Goren said he expects a mid-sized base (roughly 12 by 18 inches) to sell for $160 street. Not every mobile device will have to be retrofitted, by the way. MobileWise says it expects to see a ha
424586
Switched Mode Power Supply. Unlike the old power supplies of the past, which used large, heavy transformers, SMPS's use transistors switching DC power on and off at very high rates (typically 40 to 80 thousand times per second) into the primary of a much smaller, more efficient transformer. SMPS, in addition to being lighter and more efficient, afford better regulation of voltages. They're a bit harder to work on, but the benefits far outweigh that little inconvenience. FYI, they can also be called DC-DC converters since in a conventional setup, the house current is converted to DC by a rectifier before it goes into the SMPS. Nearly all consumer electronics products are using SMPS nowadays.
501606
i=C(dV/dt)\n\nwhere\n i= the instanious current through the cap\nC= the cap siz in farads\ndV= the change in voltage\ndt= the change in time\n\nI use this equation in my op-amp class where were are doing PWM power supplies and motor drivers right now.
602085
Go to the link below and do a search for "history of electronics" or "fundamentals of electronics" and  you will have your answer.
231878
Time constants in electronic circuits.
128687
Explain how a PIN diode works.\n\nWhat is the impact of lead length on the input of a preamp?\n\nHow does Signal/Noise affect an amplifiers sensitivity?\n\nWhat are the watts loss for a voltage regulator?
522184
Use the sine wave as 2.8 peak to peak volts to a bridge rectifier. No clamping is possible without dc power source and capacitance.
483545
I have already answered part 1. in another question you've asked. I think you probably didn't use the right units (like cm needs to be convered to meters) and got the wrong answer.\n\nNow for part 2:\n\nInduced EMF, ℰ = -L(di/dt)\n\nwhere i is the current and L is the inductance\n\nWe are given that the magnitude of the induced current,\n\ndi = 47 mA\n\nand the oscillation frequency is 100 Hz. This means that dt = 1/f = 0.01 sec\n\nWe have L = 8.44 × 10-^3 henries from before\n\nSo |ℰ| = L(di/dt) = -(8.44 × 10-^3)(0.047)/(0.01) = 0.0397 volts\n\n------------------------------------------------------\n\nNow part 3 has to do with mutual inductance:\n\nVs = VpNs / Np\n\nwhere \n\nVs is the voltage across the secondary inductor, \nVp is the voltage across the primary inductor (the one connected to a power source), \nNs is the number of turns in the secondary inductor, and \nNp is the number of turns in the primary inductor. \n\nTherefore Vp = VsNp/Ns and Vs = 0.0397 volts as calculated before, so\n\nVp = (0.0397)(197)/(2920) = 0.00268 volts
677011
Kilowatt\nCost depends on method of generation and location
388728
Please see the Wikipedia article on Electric Power Transmission below.\n\n- An electric power engineer
223189
a 400 to 500 watt power supply would solve the problem