Cell phone jammer include the universal meter, dielectric strength tester

What is the preserving temperature of a    cell phone jammer    ?
This, more suitable for high frequency electromagnetic shielding.
According to the requirements of computer systems, computer systems logically independent of DC setting. The exchange of computer systems, the security protection, lightning protection integrated directly connected to the building ground. 2, low-voltage distribution cabinet system is TN-S earthing system, the three-phase five-wire, power distribution circuit in special protective earth PE, PE lines and power distribution equipment, metal, threading pipe, connected to metal stents, etc., leakage current under fault conditions to ensure personal safety.Inspection instrument and equipment of cell phone jammer include the universal meter, dielectric strength tester, insulated resistance tester, AC millivoltmeter (or oscilloscope), wattmeter, electric load, variable frequency power supply, caliper, plug gauge and so on. 3, the DC system grounding workplace is an important part of the engine room, the project activities under the floor in the laying of 20X2 copper grounding grid, as computer systems and other potential body, each computer with a soft copper wire connected with the grounding grid, the grid that leads to the ground by the joint grounding line and the building is connected. Grounding resistance requirement is less than 1 ohm. 4, anti-static measures, the use of anti-static floor room, seating, work surfaces, anti-static floor stand ground lines should be connected with the engine room.Here is the inspection items and technical requirements of    cell phone jammer    .
The EMC shielding mechanism and classification Abstract: In this paper, electromagnetic compatibility and shielding technology basics, describes the EMC shielding mechanism and classification. For engineering applications has great practical value and significance. Keywords: electrostatic shielding electromagnetic shielding magnetic shield shielded shielding electromagnetic compatibility as an important means of control, can effectively suppress electromagnetic interference. Present a variety of electronic equipment, especially military electronic equipment, typically used in electromagnetic compatibility shielding technology to solve the problem. This article is from the perspective of electromagnetic compatibility shielding techniques described in detail the mechanism and classification. 1.Here is the appearance requirements of      cell phone jammer . Overview of shielding design is essential prior to the allocation of the overall index, 30dB and 70dB criterion is said: In general, there are in the same environment in a pair of devices, harassment immunity level and the difference is less than 30dB, the design phase can not dedicated to shielding design; if the difference between more than 70dB, shielding alone has been difficult to ensure compatibility between the two, even if we can achieve the target, no equipment costs will increase dramatically. More feasible approach is to make the overall index or program adjustments; in between 30 ~ 60dB, it is a common shield design expectations. Shielding requirements than the above expectations, the most commonly used measure is coupled with the second overall after masking the internal heavy shielding. 2. Shielding mechanism and classification according to the different mechanism of action, EMC shielding technology into electrostatic shielding, electromagnetic shielding and magnetic shielding. 2.1 Electrostatic shielding used to prevent electrostatic shield the induced electrostatic coupling.The adapter shell of   cell phone jammer has no crack, burr, deformation, scratch, shrinkage and stain.  Shielding shell material with high conductivity and good ground, to cut off distribution of two capacitive coupling between the circuits, to shielding effect. Electrostatic shielding shielding shell must be grounded. 2.2 Electromagnetic shielding electromagnetic shielding mechanism is the phenomenon of electromagnetic induction. In the external alternating electromagnetic field, electromagnetic induction shielding by induced current within the shell, and kept up screen space and the induced current produces the opposite direction with the external electromagnetic field electromagnetic field, which offset the external electromagnetic field, resulting in shielding effectiveness.