Phones with 2 SIM use one or two radio modules, the principle of operation of which is somewhat different from device boards with 1 SIM card. Dual-SIM phones have their own advantages and disadvantages, which affect the usability of the device.
Principle of operation
The number of radio modules available for use in a mobile phone is determined by the manufacturer of the mobile device. In a dual SIM phone using 1 radio module, both SIM cards are in standby mode. When a call comes to the card of one operator, the second SIM card becomes unavailable. Thus, the phone allows you to use two SIMs, but there is still only one active card. A similar situation for phones with one radio module develops when using Internet services: only one SIM can receive and transmit packet data, while the second card is in standby mode.
Devices that have 2 built-in modules can simultaneously work with two telecom operators. During a telephone conversation, the subscriber can receive a call to the second SIM-card, i.e. if desired, the user has the ability to conduct conversations with two people without interrupting the call. As soon as the telephone user answers the second call, the first conversation is put on hold. After finishing the conversation with the second caller, the user can return to the conversation with the first person.
Switch between SIM
To switch between the active SIM cards in use, manufacturers add additional features to the software of their devices. At the same time, on some phones, a button for switching active cards is additionally implemented, located on the front side or side panel of the device. Some devices present the user with 2 keys for making a call to the subscriber, each of which is assigned to each operator.
Advantages and disadvantages
Among the advantages of such devices can be noted the ability to save money on mobile communications. You can install cards from 2 different service providers in your phone. For example, the first operator can offer cheap calls to subscribers of telephone networks, and the second allows you to cheaply send SMS or exchange packet data on the Internet. For people who use two phones in the course of their life, a dual-SIM device will become an ergonomic alternative.
Among the disadvantages of dual-SIM devices, one can note their overpriced cost compared to single-SIM models. Nevertheless, in the modern mobile phone market there are a large number of budget models that will satisfy the requirements of even the most economical consumer.
