Advantages and disadvantages of card interphone

The card interphone is used by the communication network and can complete the intercom across the country without distance limitation (in the case of signal).
Ordinary cardless walkie-talkie is based on the actual power. It can talk within the effective distance without paying other fees, but there is a distance limit. The card interphone is a public network interphone, also known as the national interphone. It can often be interphone across the country, usually using the flow card One IOT network card.
The IOT network card is equivalent to the telephone card used by everyone everyday. The difference is that it is only applicable to the use of traffic. Because of the characteristics of the interphone equipment, we can use the IOT network card to talk back and send messages, but we can't view the mobile phone to access the Internet. Advantages of card interphone: Interphone throughout the country, endless distance. GPS positioning, real-time query of each position information. Be able to connect with the computer to carry out track query and review, and master the patrol information.
Figure Track playback information Background management interface, real-time query of the online status of the walkie-talkie, manipulation of login and exit of the walkie-talkie, flexible classification, and free control. Defects: The need to connect to the public network is actually the mobile communication signal. Many basements in large cities do not have communication signals, so it is not at all. That is also the biggest disadvantage of the plug-in interphone. It is also connected to the public network communication base station, so it can be infinitely spaced, so it can not be called a defect.