How to prolong the run time of cell phone jammer?

Resistor in parallel with two shielding materials, respectively, the reluctance and the reluctance of space, with the circuit analysis method to calculate the magnetic field of the shunt, which can calculate the shielding effectiveness.
The external cladding liner UV stable, moisture, wind, anti-cleaning solvent, then the internal coating of metal processing and high electrical conductivity. Another recent innovation is the EMI gasket upload a plastic clip with metal liner compared to traditional repression, its light weight, assembly time is short, and lower cost, so the more market appeal. There is no electric leakage, electric arcing and breakdown when tested according to the following conditions for the adapter of cell phone jammer.Conclusion devices generally need to be shielded, because the structure itself, there are some slots and gaps. Shielding required by some basic principles can be identified, but theory and reality is still a difference. For example, a frequency in the calculation of the size and pad pitch signal strength must also be considered, as in a device when multiple processors are used in the case. Surface treatment and long-term shielding gasket design is to achieve a key factor in EMC performance.

Low-frequency electromagnetic field analysis of a shield for many people, low-frequency magnetic interference is one of the most difficult to deal with interference, such interference is powered by DC current or AC current generated. DC transmission line of the adapter of cell phone jammer: no oxidization at DC end and no wrong connection order.For example, due to the induction furnace steel-making tens of thousands of amps of current, will produce a strong magnetic field around this control system in a strong magnetic field causes the magnetic sensitive device failure, the most common device is a magnetic-sensitive color CRT monitor. In the magnetic field, the display will occur on the screen image jitter, image color distortion, resulting in display quality is severely degraded, if not impossible to use. Low-frequency magnetic fields tend to decay rapidly with distance, so in many cases, the magnetic field sensitive devices away from magnetic interference source is a very effective reduction measures. But space constraints and can not take this measure, the shield is a very effective measure.Aging of the adapter of cell phone jammer: after the aging test, the surface temperature should be no more than 65℃; the surface and bottom shell have no deformation and burning; every performance index is within the specification range. But to note that low-frequency magnetic field shielding and RF shielding and is completely different, you can use beryllium copper RF shielding composite materials, silver, tin or aluminum and other materials, but these materials without any shielding effect of the magnetic field. Only the high permeability of the ferromagnetic alloy can shield the magnetic field. 1 according to the basic principles of the basic principles of electromagnetic shielding, low-frequency magnetic field due to its low frequency, skin effect is very small, the absorption loss is very small, and because of its low impedance, return loss is also small, so very simply by absorption and reflection difficult to obtain the required shielding effectiveness. Low-frequency magnetic field on this, through the use of high magnetic permeability material to provide bypass to achieve shielding, shown in Figure 1.Drop test of the adapter of cell phone jammer: after the drop test, the shell has no breaking, plug has no looseness or falling and the electrical performance is normal. As a high permeability shielding material, the magnetic field so as to provide a low reluctance path, so the space will be concentrated in the magnetic field shielding material, so that sensitive components from magnetic interference. Figure 1 provides a high magnetic permeability material bypass this mechanism played a role in shielding from the point of view, apparently shield the magnetic field component of the more diverting, the higher the shielding effectiveness. According to this principle, we can use the method of calculating circuit to calculate the magnetic shielding effect.