The PCB board of the adapter of cell phone jammer

Conductive pads can be used to make the appropriate size of the gap size within the prescribed limit, in order to achieve this attenuation effect. Shielding design difficult because the shield joints turn will lead to a decline in efficiency will be reduced so shielded. Note below the cutoff frequency of the radiation attenuation depends only on its diameter than the length of the gap, such as length to diameter ratio of 3 available 100dB attenuation. Perforation in need, you can use thick shield above the waveguide properties of the hole; another to achieve a high length to diameter ratio method is to attach a small metal shielding material, such as an appropriately-sized pad. Here is the switching-on inspection of the adapter of cell phone jammer.The principle and in the promotion of multi-joint case constitutes a porous shield design basis. Porous thin shielding layer: porous many examples, such as thin sheet metal air vents, and so on, when the closer spacing of the holes when the design must be carefully considered. The following shielding efficiency of such cases the formula SE = [20lg (fc / o / σ)]-10lg n which fc / o: cut-off frequency n: number of holes note that this formula applies only to the hole spacing is less than the diameter of the case can also be used to calculate the relevant metal braid shielding efficiency. Joints and contacts: welding, brazing or soldering is thin between the common way of permanently fixed, occupies a position of metal surfaces must be clean, to make the joints completely filled with a conductive metal. The components inside the adapter of cell phone jammer should be the same as those inside the sample.Not recommended for fixed with screws or rivets, fasteners because of the low resistance junction between the contact state is not easily sustainable. Conductive pads is to reduce the slot seams or joints, holes or gaps, so that RF radiation is not distributed out. EMI gasket is a conductive medium, used to fill gaps within the shield and to provide a continuous low impedance contacts. EMI gasket are usually between two conductors can provide a flexible connection, so that the current spread on a conductor to another conductor. EMI gasket sealing the choice can refer to the following performance parameters: The shielding efficiency of a particular frequency range Adhesion method and seal strength Compatibility with the current housing and the corrosion resistance of the external environment.  The tin-coating of the component inside the adapter of cell phone jammer is good without dry joint and build-up.Operating temperature range Cost of most commercial pads have sufficient shielding to enable equipment to meet EMC standards, the key is properly within the shield design of the gasket. Gasket system: a key factor to consider is compressed, the compression gasket in between the liner and high conductivity. Gasket between the liner and the poor will reduce the conductive shielding efficiency, the other joints occur if the less a slit-shaped groove formed by the antenna, the radiation wavelength smaller than the gap length of about 4 times. Ensure continuity gasket surface first to ensure a smooth, clean, and by the need to address in order to have good electrical conductivity, these surfaces must be covered before the engagement; other cushioning material such shielding gasket bonding with continuing good also very important. The PCB board of the adapter of cell phone jammer has no short circuit, open circuit and the copper sheet has no tilting.Compressibility characteristics of conductive pads can make up any irregularities in the gasket. All pads have a minimum contact resistance and effective work, designers can increase the compression strength of the cushioning pads to reduce the number of the contact resistance, of course, this will increase the sealing strength, the shield will become more curved.