Free repairing for three years and life-long maintenance for this type of cell phone jammer

As frequency increases, the ability to enhance the electromagnetic radiation, electromagnetic interference tends to far field for plane wave shielding theory based. Even cell phones still show signals when the  cell phone jammer is working, they can’t communicate anymore.In the far field, the electric field interference and magnetic interference can not be ignored, need to implement shielding of electric and magnetic fields. The conductive material can be used to good shielding and grounding, and can also play the electric and magnetic shielding of the dual role. Electromagnetic shielding and grounding and shielding are not linked. The real impact of the shielding effectiveness of the shield only two factors: one is the entire surface of the shield conductivity must be continuous, the other is not directly penetrate the shield conductor.
For the shield, the material chosen for its great impact on performance and cost. In the design of the shield, the shield to understand the different characteristics of the alloy. It is just gloss that cell phones show signals even when the    cell phone  jammer is working.Performance of these different understanding of the material, help to select suitable materials to meet application requirements.
Electromagnetic shielding materials currently used mainly in metal-based materials such as aluminum, copper, zinc, iron, steel, nickel and their alloys.
Pure electric or magnetic field interference is rare, commonly referred to as electromagnetic interference is the existence of both electric and magnetic fields of high frequency electromagnetic interference. Free repairing for three years and life-long maintenance for this type of    cell phone  jammer  . Electromagnetic shielding for sensitive equipment and sources of interference suppression when the distance generated by coupling electromagnetic field interference, it must be shielded electric and magnetic fields, usually in a good conductor of small resistivity materials, space, electromagnetic interference in the incident to the metal surface will of reflection and absorption of electromagnetic energy is attenuated, and thus play a role in shielding.
Electrostatic shielding and static magnetic shielding material is easy to achieve a good conductor, but in the alternating electromagnetic field, the electric and magnetic fields always exist in the same space, so the electric and magnetic fields must also consider shielding.Why cell phones still show signals when the    cell phone  jammer   is working? However, due to the different frequency, alternating electromagnetic interference [5,6] effects of different areas, practice should be treated differently.
When the frequency is low, electromagnetic interference mainly in near-field region, based on application of electric dipole and magnetic dipole near-field shielding theory. In the near field, with the interference of a different nature, the size of the electric and magnetic fields are quite different. High voltage low current main source of interference to the electric field, can only consider the neglect of electric field shielding magnetic interference; low-voltage high-current interference with the main magnetic field, magnetic field shielding can only consider the neglect of electric field interference.