What is Magnetic Shielding?
Aluminum can shield certain frequencies, but not all of those used in the RFID cards. These cards range from 125 KHz to 134.5 KHz to 13.56 MHz and higher. The cards in the mid range can be shielded, but foil and aluminum will not work on the lower frequencies. RFID cards can be door access cards, debit and credit cards, the REAL ID drivers license, MARTA transportation passes, store loyalty-shopping cards, passport cards, employee badges and many other types of cards. Notice certain vendors do not cover or discuss all these cards, and only limit their claims to certain RFID cards for shielding.
The American made Armadillo Dollar will shield and block RFID frequencies on all of the above mentioned cards.
Check out http://www.ArmadilloDollar.com
Magnetic shielding is a process that limits the coupling of a magnetic field between two locations. Magnetic shielding can be done with a number of materials, including sheet metal, metal mesh, ionized gas, or plasma. The purpose of magnetic shielding is most often to prevent magnetic fields from interfering with electrical devices. Magnetic shielding is necessary because, unlike electricity, magnetic fields cannot be blocked or insulated. This is explained in one of Maxwell’s Equations, del dot B = 0, which means that there are no magnetic monopoles. Therefore, magnetic field lines must terminate on the opposite pole. There is no way to block these field lines; nature will find a path to return the magnetic field lines back to an opposite pole. This means that even if a nonmagnetic object – for example, glass – is placed between the poles of a horseshoe magnet, the magnetic field will not change. Instead of attempting to stop these magnetic field lines, magnetic shielding re-routes th
: There exist no 100% effective known shield against magnetism. Magnetism will pass through any material, and I mean anything, glass, plastic, water, insulation, even you. Some materials basically conduct magnetism better then others, just like electricity. If you want to shield something from magnetism, like your speakers, you would use a high permeability material and surround the item to be shielded to move the magnetism around it instead through the item. Delicate instruments like meters, the ones with those dials have exactly this installed around the sensitive meter, because magnetism would interfere with a correct reading. Anyway, a Scientist of the name Hans Christian Oersted, was the first to emphasize the relationship between electricity and magnetism in 1819. He discovered that a compass would act very strange while very close to a flowing circuit and then it would go back to it’s normal reading after the circuit was turned off. From this we learned that you can also make a
the process of limiting the flow of electromagnetic fields between two locations, by separating them with a barrier made of conductive material. Typically it is applied to enclosures, separating electrical devices from the ‘outside world’, and to cables, separating wires from the environment the cable runs through. Electromagnetic shielding used to block radio frequency electromagnetic radiation is also known as RF shielding.
