Sound

Sound is probably one of the most common representation methods for information. Sound can be used in many different ways:



Uses/Advantages of Sound

· face-to-face conversation
· telephone conversation
· announcements in shops/airports
· sat nav instructions
· podcasts
In order to be able to access information conveyed by the methods mentioned above, you would need to be able to speak the language and not have any hearing impairment.
However, this does not mean you will be able to access the information. There are factors which may interefere with you being able to hear the sound clearly. For example:

Issues/Disadvantages with Sound

· Strong accents
· A lot of background noise
· Muffled speaker systems
· Poor receptions i.e. mobile calls
· Illness such as cold which affects your hearing

Costs

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SP-S110 2.0-CH Basic Stereo Speaker System - Black
SP-S110 2.0-CH Basic Stereo Speaker System - Black

Basic Speaker System
Cost: £6.23











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Advanced Surround Sound System
These can cost anywhere from £300 to thousands of pounds depending on much it is customised etc.












Sample Exam Question on Sound:

Q. Give Details of 3 ways in which sound can be used and 3 issues that may arise when doing so:
A. Sound can be used for:
- Face to Face Communication
- Telephone Communication
- Announcements in shops/airports etc
3 Issues that may arise during these interactions are:
- Strong accents make sound hard to understand
- Telephones may pick up background noise which is not useful
- Bad reception on mobiles may cause sound to be muffled or hard to understand.




LEDs

Definition

A Light Emitting Diode or LED is a semiconductor light source that emits visible light when charged with an electrical current.

Information on LEDs

LEDs are commonly integrated into many household appliances in order to provide you with information. This information is often to tell you whether an appliance is switched on or off, for example:
· Televisions
· computers and monitors
· answer phones
· kettles
· clock radio alarms

They can also be used to indicate that something else has happened, for example:
· pressing the 'caps lock' button on your keyboard will light up the caps lock led
· flashing light on answer phone will indicate that a message has been received
· flashing light on burglar system to indicate that the system is active

General Points

· As well as single LEDs being used in household appliances, technology has enabled them to be incorporated into information systems such as the examples below*.
· Electronic information display systems have been used for many years in places such as airports and train stations.
· They generally consist of a large LED board either hanging from the ceiling or placed on the wall. The board displays basic details of all incoming and leaving flights/trains.
· The board is updated regularly either by a person or automatically by software to ensure that the information displayed is correct and up-to-date.
· As well as large boards such as the one above, single or multiple line LED message boards are now commonly being used to convey information and messages to the public.
· They are also used a lot in companies where time matters! For example a call centre might display the average time people are waiting in the queue, which is meant to motivate the call centre staff to work faster!
· As technology has moved on and prices have come down, LED information systems are commonly found in many public areas such as banks, hospitals, schools, cinemas and reception areas. Here are a few examples*:
1. Hospital
2. Bank
3. School
4. G.P. Surgery

LEDs are even being used on the front of buses to display the bus number and route.
The technology works by using a series of dot matrix arrangements. The appropriate dot is lit up to display the required text message.
The LED outputs light which is much brighter than normal daylight or light bulbs. This makes it viewable in most conditions and locations.

For advantages and disadvantages follow the link:

LED's Pro's and Con's

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LED colours
LED colours

In terms of cost LED’s such as the picture to the left can cost only a few pence if bought in bulk which is usually the case.





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However some LED products such as the latest LED TV’s as shown in the picture to the left can cost anywhere from £200 (for a cheap small one) upwards.







Sample Exam Question on LED’s

Q. List 2 ways in which LED’s can be used and how they would be used in that situation:
A. 2 Ways in which LED’s can be used:
- Monitor’s in G.P. Surgery: LED’s can be used on DOT Matrix screens to show what patient is next in the queue.
- Televisions: LED’s are frequently used on televisions to show if the TV is on or off. This is usually indicated by a red light or green light – red being on and green being off.




DOT Matrix Screens/Displays


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Information

A dot matrix display is a display device used to display information on machines, clocks, railway departure indicators and many and other devices requiring a simple display device of limited resolution. The display consists of a matrix of lights or mechanical indicators arranged in a rectangular configuration (other shapes are also possible, although not common) such that by switching on or off selected lights, text or graphics can be displayed. A dot matrix controller converts instructions from a processor into signals which turns on or off lights in the matrix so that the required display is produced.

Common sizes of dot matrix displays (Resolutions):
§ 128×16
§ 128×32
§ 192×64

(There is literally no information on these. You keep getting linked to DOT Matrix screens)




Braille Printers

Definition (Braille)

Braille is a writing system for blind and visually impaired people. It is made up of raised dots that can be 'read' by touch.

How it works

Braille Printer (Braille Embosser)
A Braille printer operates by embossing raised braille dots onto braille paper. Pins are pressed into one side of the paper in order to create raised dots on the other side of the paper.

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Advantages

Braille is a primary medium of reading and writing for people who are blind or have low vision. Many blind and visually impaired individuals find that they can access information more quickly and perform tasks that involve reading or writing more efficiently using braille than by listening to a personal reader, dictating to a personal secretary (otherwise known as an amanuensis), or using alternative technologies such as audio recordings, talking computers, or other electronic devices. Experienced users of braille are often able to read or take notes in braille much more quickly than they can using other methods.
In the workplace and at school, knowing braille makes it possible for blind people to read and take notes independently, and it increases the amount of written material that is accessible to them. For example, braille can be used to write notes for a business presentation or a speech.
In daily life, there are many situations in which braille offers the best choice for independent action. For example, in restaurants blind people can make selections from braille menus without the assistance of a waiter or another diner.

Cost

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Cost: Anywhere from £1,120 to £3,120.










Sample Exam Question


Q. Braille is a writing system for blind and visually impaired people. It is made up of raised dots that can be 'read' by touch.

A. A Braille printer operates by embossing raised braille dots onto braille paper. Pins are pressed into one side of the paper in order to create raised dots on the other side of the paper. It is used mainly by blind people/people with bad vision. Many blind and visually impaired individuals find that they can access information more quickly and perform tasks that involve reading or writing more efficiently using braille. In the workplace and at school, knowing braille makes it possible for blind people to read and take notes independently, and it increases the amount of written material that is accessible to them. For example, braille can be used to write notes for a business presentation or a speech.







Sources of Information

TeachICT
Wikipedia
Google (In general, inc. Google Images)


- By Paul Ellison


Side Notes:
1). Pictures won't display for some reason. Not 100% sure why.
2). Couldn't find information on everything - Mainly a lack on DOT Matrix Screens.
3). Wikispaces has deleted this 3 times now for no reason.