How do you build a microwave shield?
467769
This is an important question - the health effects of microwaves.  Some comments: Lead is not necessary.  Lead stops ionizing radiation like x-rays, but for reflecting microwaves, any conductive metal will do; aluminum is the most commonly used for microwaves, and is a better conductor than lead.\n   Metal mesh will work, just like in a microwave oven, but the problem is, it will only be really effective if you build a sealed box.  If you only cover the windows, the microwaves will come through the walls, floors and ceiling.  Also, at the joints between sheets of metal mesh, you need to have a continuous eletrical connection.  Any seam which is unconnected over a few inches will allow power in.  A large seam may behave just as if the mesh is not there at all.  (This is why a cell phone will sometimes work in an elevator, and sometimes not)  \n    I would think that using aluminum adhesive tape running down the seams of the mesh on both sides would work. \n    Anything that only covers one wall or less may help, but it may not help at all, as microwaves bend around the edges of shields, and also are reflecting off all the other parts of your building.  Any non-sealed metal mesh structure will interact with the radiation field as a open metal resonator in a very complicated way, which is hard to predict and depends on the specifics of the metal geometry, the direction and frequency of the radiation, and all the collection of reflectors in your building (pipes, wiring, window screens, reinforcing bars in concrete).  However, if the metal mesh box is truly sealed and has no open seams whatsoever, you are 100% safe.  People build these out of mesh for low-noise testing chambers, but they are hard to build, especially around doors and inlets for electrical wires and plumbing.  It really is a huge undertaking for a non-professional, sorry.\n     One final comment: you can take some comfort in the fact that if what you see outside your window are dishes, they are highly directional antennas.  Typically, they direct nearly all of their power in a cone within 1 to 4 degrees angle of the satellite or receiver where they are aimed.  Typically, stray radiation (called sidelobes) are 30 dB lower, meaning that the power radiated in other directions is one thousand times lower.  \n      Cell phone towers, however, which do not look like dishes, but an array of typically three or more panels, are not directional, and spray alot of microwave power in all directions.\n     Is there a health risk?  I'm director of a microwave engineering firm, and I don't know the answer for sure.  Just not enough data.  In my own laboratory, however, I always take all precautions to make sure no one is ever exposed to any microwave radiation, just in case.  There are national standards which govern the equipment outside your window, which do specify a maximum 'collateral' radiation level, which is deemed to be safe, based on what data does exist.  I would tend to believe that it is extremely likely they are correct about these levels being safe (safe meaning less likely to hurt you than the air pollution you breathe, the chemicals in the products you use, etc.), but we cannot be 100% sure.\n    Personally, I would be fine with living in an apartment looking out on a bunch of dish antennas, but if it was directly adjacent to a cell phone tower or building with cell phone array on it, I would not want to expose my family to it, and would move out.
489055
1. Get a common heavy pliers.\n\n2. Get a common three- or four-tined eating fork.\n\n3. Use the pliers to bend the inner tine(2) back at the base to a 90-degree angle, so that only the outer two tines are facing out.\n\n4. Fill a Dutch oven withabout three inches of water.\n\n5. Wet a standard bath towel.\n\n6. Proceed to the nearest operational electrical outlet providing at least 10 amps of 120 volt, single-phase alternating current.\n\n7. Place the wet towel on the floor near the outlet.\n\n8. Place the water-filled Dutch oven on top of the towel.\n\n9. Remove your shoes and stand in the Dutch oven, ensuring your feet are covered with water. \n\n10. Insert the fork in the outlet, making contact with the home wiring.\n\n11. Die, and spare the world another person so dumb, he asks on Yahoo! Answers how to violate the Yahoo! Terms of Service and invade other Yahoo! users' privacy.
708373
Take an old cardboard box and line it with aluminum foil. then cover the flaps of the box with foil as well. take this outside in the sun and use the flaps to shine all the rays on a biscut or cookie dogh. it will cook it, it may take a while but it is a solar cooker.\nLet me know how it works out.
294472
You need something called a fire wall.  You can download a very good one at zone labs.  It's free...
968430
its not the fact that he can or cannot use a microwave, I myself reside in SaudiArabia and am currently using a sears kenmore microwave.. we have both 110 and 220 voltage.. and they sell converters commonly in all hardware stores.. \nI would be concerned more with the shipping of the appliance.. The workers commonly hired in companies here dont take much care with items being shipped, it will be jostled, thrown, and crunched probably before your friend gets it.. It wouldnt work properly and might be a fire hazzard.. Unless by some means it is shipped via the military shipments..\nnote: brandy's suggestion is the best.. just send money and your friend can then use it to buy what they need best.. ^_^
128346
Ok, this is how you do it.  You need to have the following items: A coil of copper wire, a barrel shaped magnet, a tube, and a bulb.  Take the tube, and this could even be a paper towel cardboard center, and wrap coils of wire around the outside of the tube as many times as you can.  This should cover the outside of the tube.  Now, take the two ends of the wire and connect them to the + and - of the bulb that you will be using.  You must then place the magnet (a barrel magnet is best, but any will do.  The stronger the better) inside the tube, and cover both ends of the tube.  Now, as long as you are shaking the tube lengthwise, and the magnet slides up and down inside the tube, the bulb will shine.  To make a more practical flashlight, you could do one of two things.  Either have an electrical storage device that will hold the charge so you don't have to keep shaking it, or you could rig something up that will keep the magnet moving inside.  Either or both will work.
443133
hi,\n\ntransformers you can buy for pretty cheap at any decent electronics or  hobby stores (radio shack sucks these days, but they probably still have them).  \n\nhowever you can make them really easily.  all you need is a hunk of steel or iron (some kind of rod-shaped thing would work, as would a donut-shaped loop).  take one wire and wind it around the piece of steel N times.  take another wire and wind it around a different part of the steel M times.  congratulations, you have just built a transformer that will step up/down voltages by a factor of M/N (or N/M, if you hook it up the other way.)\n\ncheers-
147664
It's not clear from your question, are you trying to design an antenna?  What is the purpose of this experiment?\n\nIf you want to build an antenna, I would suggest a magnetic dipole.  This is the old fashion UHF type attenna (the loop).
1042847
get some alluminun foil and make it into a long snake    wrap it around the antenna   if possible  physically extend the antenna   also haveing alot of alluminum foil nearby the antenna helps   if you have any high speed usb ports on your computer   plug the adapter into them
214606
well, microwaves are an electromagnetic wave, so pretty much any method of conducting, redirecting and conditioning microwaves is essentially magnetic in nature.\n\nthe person who suggested waveguides is on the right track; these are simply rectangular (or circular) tubes with dimensions that are of the wavelength of the waves you want to control.\n\nthe keyword you want to search on the web for is "microwave optics":\nhttp://www.google.ca/search?hl=en&q=microwave+optics&meta=\n\ncheers!
408213
Ok. Try This.....\n\nStart with a clear glass or plastic jar, some stripped wire, a strip of aluminum foil, and a larger piece of aluminum foil. \n \nBend the wire over the top of the jar so that it goes over the middle and is wrapped around the opening of the jar. Now fold the aluminum foil strip over and drop it over the wire, so that it hangs down into the jar.  \n\nNext take the larger piece of aluminum foil: make it roughly circular by cutting or folding the corners underneath, and press it over the top of the jar. Next wrap electrical tape (or any tape) over the edges of the aluminum foil holding it to the jar. Finally smooth out any bumps in the foil. \n \nYour electroscope should look something like this. \n \nComb your hair a few times and hold the comb close to the top of the electroscope. The ends of the aluminum foil should push away from each other because of electric charge. \n \nYou can discharge the scope with your hand while holding the comb close to the top of the scope. \n \nMove your hand away. \n \nMove the comb away. \n \nA charge has been induced into the electroscope. When you were discharging the scope charge remained close to the comb and when you moved the comb away that charge was released to spread through the rest of the metal parts including the aluminum strip. \n\nHope this helps.
527700
Remove the plate, deconnect the plug from the box and pushed it into the box. Replace the cover with a solid cover plate and put epoxy over the screw head. If you need the socket, break the cover plate and remove the screws with pliers. \nNot pretty but effective.
205891
Oh, this one is easy. \n\nGo out into space (probably just inside the asteroid belt), and build a 30 kilometer long linear accelerator made out of low impedance electromagnets. Attach it to a huge solar collector, a huge capacitor bank, and a transformer to transform whatever voltage the collector recieves voltage at, to just below the breakdown voltage of your capacitor or electromagnets (whichever is lower).\n\nAssemble a big paramagnetic rod out of something nice and massive (like iron), and coat it with a few thousand tons of lithium, or something similar in reactivity. The entire projectile should mass no less than ten thousand tons. \n\nCharge up your capacitor bank, point the accelerator at the Earth, and tell them to turn over control of all governments to you, or you're going to hit the Earth with a very large plasma projectile traveling at a very high rate of speed...
183707
Follow the bottom 2 links that I am going to post to get a labeled schematics\n\nhttp://www.kids-online.net/learn/click/details/sblvalpci.jpg\n\nhttp://dmzweb4.europe.creative.com/wwimages/audio_int/sblive/liveplayerconnect600.gif
736491
********************************************************\n\nIf you ask me, one of the cleverest parts of a microwave oven is the door. It lets you see into the oven to make sure your potato isn't about to explode, yet keeps your face from being cooked off by microwaves in the process. It accomplishes this remarkable feat with a metal mesh—basically a sheet of metal with a regular pattern of small holes drilled or punched in it. This, along with the metal material of the oven cavity itself, forms a sort of reverse Faraday cage. A Faraday cage is a metal enclosure that normally keeps electrostatic fields and RF (radio frequency) radiation from getting in, but in the case of the oven, from getting out.\n\nA solid sheet of metal would be the most efficient at containing RF, but since you can't see through metal (unless you happen to be Superman), a compromise must be made. How much RF escapes through the mesh depends largely on two factors: the wavelength of the radiation in question, and the diameter of the holes. (For you picky types, the conductivity of the mesh material has a slight but negligible effect, as does the shape of the holes, among other things.) The shorter the wavelength of the RF, the smaller the holes need be to block the radiation. Microwave ovens operating at 2450 MHz emit radiation with a wavelength of about 12 centimeters, and the holes in the mesh of the door are typically on the order of 1-2 millimeters in diameter. Since the holes are small compared to the wavelength of the microwaves, little radiation can leak out. There are also mesh screens on the sides of the oven cavity, one to protect the oven light while allowing it to shine into the cavity, the other to permit ventilation.\n\nThe FDA has set emission standards for new microwave ovens at a power density of 5 milliwatts per square centimeter at a distance of 5 centimeters from any point on the outer surface of the oven. Typical new ovens have a leakage of only 0.2 mW/cm2 at that distance—a tenth of the FDA standard. Dirt, mechanical abuse and everyday wear and tear can eventually reduce the effectiveness of the door seals, thus increasing leakage. If you're concerned about emissions from an older oven, you can purchase leakage sensors at many hardware and home improvement stores or online. Keeping the seals on the oven and door clean, as well as opening and closing the door gently, will help keep your oven safe to use. So go ahead and ogle your latest culinary masterpiece while it cooks. Your food will cook, but your head will not. Or so one certainly hopes. \n\n**************************************************************
864101
what you do is you get 3 chunks of that foam stuff used for packing (not the peanuts the little bricks)\nmake sure they are about an inch thick.... alternatively you can use chunks of wood NO METALLIC OBJECTS!!!!!!!\n\nthen get your hands on a small clear vase or you can also use a big drinking GLASS\n\nset the blocks in your microwave, in a pattern that will let you set the glass upside down on the platter but you can still get your finger into the glass from the bottom.....\n\nlight a match and stick it directly under the glass...\n\n(the blocks help the match get air)\n\nset the microwave to high for 20 seconds.... you will see an awesome light show inside the glass, the glass will NOT be hot and will NOT explode, as well as your microwave will NOT be harmed\n BUT\n\nthere is a gas formed by this method of plasma creation...\nto us its poisonous, im not sure what it is exactly but dont breath it, it will not stay on items or taint items but if you BREATH it you can get sick.\n\nyou can choose to clean the glass and use it again and again and not have any problems as there was no residue to clean to begin with... or\nyou can just chuck it.\n\nalternatively you can just run over to spencer's gifts and pick up a plasma globe
211344
Its in Wikipedia, the free encyclopedia, just type the "Faraday cage" in yahoo search you will find the 75% for your answer and rest you do your home work.