Sim Cards and Memory Cards – JSS1 Computer Hardware & GSM Repair Lesson Note (Second Term)
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- Subject
- Computer Hardware & GSM Repair
- Class
- JSS1
- Term
- Second Term
- Topic
- Sim Cards and Memory Cards
- Order
- Topic 4 of 8 this term
- Reading time
- 5 min
A SIM card identifies you to a mobile network, while a memory card gives a phone or camera extra space to store files.
Behavioural objectives
- State what SIM stands for and define a SIM card and a memory card.
- List the functions of a SIM card and a memory card.
- Name the types of SIM card and memory card by size.
- Explain how to care for SIM cards and memory cards.
- State the differences between a SIM card and a memory card.
What is a SIM card?
A SIM card is a small chip card that identifies a subscriber to a mobile network.
- SIM: stands for Subscriber Identity Module.
- Simple picture: it works like your phone’s ID card or passport on a network.
- Without it: the phone cannot make normal calls or send SMS, even if the phone itself is working.
- Network providers: MTN, Glo, Airtel and 9mobile each issue their own SIM cards.
What are the functions of a SIM card?
A SIM card links your phone number to your network provider.
- Phone number: it gives you a phone number.
- Network connection: it connects you to your network provider.
- Calls and SMS: it allows you to make calls and send text messages.
- Mobile data: it lets you use the provider’s data service when you have a data plan.
- Contact storage: it can store a small number of contacts and messages.
- Moving numbers: you can move the SIM to another phone and keep the same number.
What are the types of SIM card?
There are three common types of SIM card by size: standard, micro and nano.
- Standard SIM: the biggest one, found in older phones and hardly used in new phones.
- Micro SIM: a medium size, used in some older smartphones.
- Nano SIM: the smallest size, used in most modern smartphones.
- Why they shrank: phones became slimmer, so the cards had to become smaller.
- Same chip idea: all three carry the same kind of gold contact chip.
| Type | Size | Where it is used |
|---|---|---|
| Standard SIM | Biggest | Older phones |
| Micro SIM | Medium | Some older smartphones |
| Nano SIM | Smallest | Most modern smartphones |
What is a memory card?
A memory card is a small removable card that stores files such as photos, music and videos.
- Other name: it is often called an SD card, short for Secure Digital.
- Cupboard picture: the phone’s internal space is like a small cupboard that can get full.
- Backpack picture: a memory card is like an extra backpack that carries more things.
What are the functions of a memory card?
The main function of a memory card is to give extra storage.
- Storage: it keeps photos, music, videos and other files.
- File transfer: it lets you move files from a phone to a computer easily.
- More free space: moving files onto it frees the phone’s internal space, which can help the phone work better.
- Backup: it can hold a copy of important files.
What are the types of memory card?
The two common types of memory card are the SD card and the microSD card.
- SD card: the full-size card, used in digital cameras and some computers.
- MicroSD card: the tiny card that fits inside almost all mobile phones.
- Adapter: a microSD card can be placed in an adapter so that a computer’s SD slot can read it.
How do you care for SIM cards and memory cards?
You care for these cards by keeping them clean, dry and handled gently.
- Keep off the gold: the gold-coloured metal lines are the contacts, and oily or dirty fingers can stop the card from working.
- Avoid water: if a card gets wet, dry it gently with a soft cloth and let it dry fully before use.
- Do not force it: if the tray will not slide in easily, stop and check that the card faces the right way.
- Protect the phone: forcing a card in can damage the metal pins inside the phone.
- Safe eject: pulling a memory card out of a computer suddenly can corrupt (damage) your files.
- Store safely: keep spare cards in a small case, because they are easy to lose.
How do you remove a memory card safely from a computer?
- Save your work and close any file from the card.
- Click “Eject” or “Safely Remove Hardware” on the screen.
- Wait for the message saying it is safe to remove.
- Pull the card out gently.
How do you put a SIM card into a phone?
- Switch off the phone.
- Open the card tray or back cover.
- Match the cut corner of the card to the tray, with the gold side facing the correct way.
- Slide the tray or card in gently.
- Switch on the phone.
What is the difference between a SIM card and a memory card?
A SIM card identifies you and connects you to a network.
A memory card stores your files and does not connect you to a network.
| Feature | SIM card | Memory card |
|---|---|---|
| Main job | Identification and connection | Storage (saving things) |
| Storage | Very small (contacts and SMS) | Very large (photos and videos) |
| Network | Needed for calls and data | Not needed for calls |
| Key part | Gold contact chip | Gold contact chip |
Evaluation
- What does SIM stand for?
- List three functions of a SIM card.
- Name the three sizes of SIM card, from biggest to smallest.
- Why is it a bad idea to touch the gold part of a memory card?
- You buy a new phone and want to keep your old number. Which card do you move to the new phone?
Assignment
Ask an adult at home to show you a SIM card. Write down the network name on it and say whether it is a standard, micro or nano SIM.
This term's Computer Hardware & GSM Repair topics
JSS1 Second Term · 8 topics
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