28 September 2016
Duration: 4:55

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What you need to know about how mobiles work including topics like SIM cards, signal strength and more.

In today's world a mobile phone is an important tool. It keeps you in contact with your loved ones and it's extremely valuable in an emergency. With a mobile phone in your pocket, help is only a few button presses away. If you understand how your mobile works, then you'll understand when it can help you and when it can't.

Let's take a look. A mobile phone is actually a compact radio. It communicates with the nearest mobile phone transmission tower. Now you do need that radio link for the mobile to work. We referred to the strength of this link as the amount of reception a mobile has.

At the top of your mobile screen, this small set of bars shows the strength of the connection. The more bars means a stronger signal. When there are only one or two bars, the voice quality of the call may not be as clear as it would be with a full strength signal. The call might also disconnect and others might have trouble reaching you.

If you're on a call and the signal becomes weak, try walking a short distance to find a spot with better reception. Now how do you pay for your mobile calls? Well when you buy a mobile phone you need to buy a mobile phone number as well. The number is associated with your mobile phone account which you access through a small micro chip on a card called a sim.

The sim card gets inserted into your phone when you purchase it. Without a sim, your phone can only call triple 0 emergency. Insert the sim into the phone and you'll get access to a mobile network. You can make calls to any number via the network that matches your sim. If you have a Telstra sim for instance, you can call any Telstra and non Telstra number. Just like you can with your home phone. Just like your home phone, the call costs go onto your account.

You can of course receive calls made from any network. Most mobile phone calls are charged like long distance calls. Each time you dial a number, the mobile service provider charges you a flag full fee and then a permanent fee. This might sound expensive but phone companies offer arrangements that give you a large number of calls at a set cost. These are called Kept plans and might for example, cost $40 a month but give you something like $300 worth of calls.

You should discuss these with the mobile service provider you buy the sim card from and you should always read all the details about the charges. Depending on your mobile service provider, you might have to sign a contract that lasts one or two years. The good thing about a contract is that you don't need to pay for your mobile phone on the spot. The cost of the phone can be spread over the length of the contract.

Most providers also offer an insurance plan for your phone so if you lose or break it, it will be replaced for much less than the cost of a new phone. The insurance plan will likely involve an additional cost so be sure to ask your provider about it. Mobile phones range in cost from less than a hundred dollars to up around a thousand dollars.