In terms of energy saving and heat dissipation, the built-in cell phone signal blocker is a little worse than the external mobile phone signal blocker. From the external structure, the built-in mobile phone signal shield is a combination of the transmitting antenna, power supply and heat sink in a body of external plastic shell, in appearance, to be more beautiful, convenient, plug and play and other advantages, applied in some schools, meeting rooms, confidential places with high traffic occasions have great advantages.
The external mobile phone signal jammer, from the structure, it takes the thickening of pure aluminium alloy, through the oxidation of baking paint and other processes, the circuit board and the shell combination, the full use of its own shell to achieve good heat dissipation, because the antenna using SMA head external connection, the power supply is external inconvenience for long-term mobile use, the operation is more complex, and the installation is also inconvenient, but its own advantage is also very strong. Is very strong, external heat dissipation effect is very obvious, this is because the transmitter antenna external and shielding of the mutual matching, so that the heat dissipation effect is better. Because the external signal jammer power supply and host is separate, so can reduce the burden of the host, so that the external mobile phone signal shield can be better stable long-term work. Comprehensive the above characteristics, Dazhan electronic external mobile phone signal shield is more suitable for application in school classrooms, student dormitories, churches, troops, prisons, detention centres and other fixed occasions that require a long time of continuous work and stable use.