COMPUTER HARDWARE

Computers have become a vital tool in modern communication, both for office work and for the production of high quality audio and video with a considerable decrease in effort. Computers and digital technology have developed hand in hand over the last few decades, as digital storage was initially a system conceived for computer data.

There are two vital components to any computing system:

• The hardware. This is the wiring, electronic circuits, disc drives, monitors, keyboards and so on that make up the physical machine we call a computer.

• The software. This is the term used to describe the programmes that we use on the computer.

Hardware and software must work together if we are to get anything useful done with a computer.

Your choice of computer hardware will differ according to your needs and according to the kind of software you are planning to use on your computer. In general, however, all computers share certain basic hardware:

The CPU tower or cabinet
 
All computers need a case to house all the electronic components. Cases can come in a variety of colours and shapes, but all of them have the same purpose - that is, to hold and protect the electronic components. Modern CPU towers are usually of the ATX or Micro-ATX variety, which means they automatically switch the power off when the computer is shut down. It is agood idea to assess how large a case you need based on the number of peripheral systems (CD-ROM drives, CD-writers etc.) that you plan to install internally - these are usually accessed through configurable slots in the front of the system, and smaller cabinets have fewer slots.

The computer's power supply is normally supplied with the case. This power supply, called an SMPS (Switched Mode Power Supply), is basically an AC to DC convertor; and can come in a variety of ratings: 200 Watt, 300 Watt and 450 Watt are most common.

Plan ahead and get a more powerful SMPS than you need if you intend to add more components later on to the system. (But remember that it will still consume its rated power whether you actually install those components or not!)

The SMPS usually has a fan fitted on it which is visible at the back of the cabinet: This is because the power conversion process generates a lot of heat which needs to be vented.


Motherboard
 
The motherboard is a large circuit board into which all the other components are plugged: The motherboard supplies power to all the components and connects them together, transporting data from one component to the other. The motherboard is mounted in the computer's case, and has slots and connectors for the other components

Motherboards vary in terms of speed and features. More expensive boards tend to be faster, more reliable and support more features and advanced components. It is important to match a motherboard to the processor unit that you install, as many of the features can be interdependent: A fast processor can be hampered by a poor motherboard, or a fast motherboard can be underused by a slow processor.

Processor and peripheral manufacturers usually specify the best motherboard solutions for their equipment, so it's always worth having a look at those while deciding your configuration.

Last but not least, it is always worth considering how futureproof your motherboard is in terms of plugging newer peripherals into it: You may like to increase the RAM or plug a different card into one of the slots later on, and you should explore whether this will be possible at a later date.

The Central Processing Unit (CPU)
 
The CPU can be thought of as the brain of the computer. It is the part of the computer that does the actual computing, and co-ordinates the actions ofthe whole system. Software programs are written to give the CPU a set of instructions. The CPU will follow the instructions to accomplish a specific task. The two principal CPU manufacturers globally are Intel Corporation and Advanced Micro Devices (AMD).

Like all other components, the CPU is connected to the motherboard. It is easy to spot on the motherboard, as it usually the largest microchip on the board. This is why it is often called the chip for short. The CPU is covered by a cooling fan, as modern CPUs are very powerful and compact, and generate a lot of heat.
Computers are often differentiated by the type and speed of their CPU. For example, in terms of type, people may refer to a computer as a Pentium III or Pentium IV or as an AMD Dual Core Turion.: This means that the computer has a Intel Pentium III or IV series processor or an AMD Dual Core Turion processor installed.

The processor name also usually has a number and a frequency attached like Pentium IV 2.4 GHz, for instance. The 2.4 GHz refers to the speed of the CPU and indicates that it can operate at a speed of 2.4 GHz (or 2400 MHz). This means it is actually capable of doing 2400 million operations per second, which should indicate just how fast modern computers are.

The newest type of processors actually carry two processor chips in one casing - 4 and 8 chip versions are also beginning to make an appearance, but are still very expensive. These types of processors are called Dual Core processors, and are quickly becoming the modern standard for computer CPUs.

Random Access Memory (RAM)
 
The CPU has to process digital data to carry out instructions. This data has to be stored so that the CPU can quickly retrieve the data, process it and save it again for further processing. This storage space used to hold the data that the computer is working with at any time is referred to as the computer's memory. Memory is like the CPU's scrap paper - somewhere to write down notes and calculations as it works. It is referred to as Random Access Memory (RAM). RAM is storage space that is available for shortterm storage of data.

RAM relies on a constant presence of electrical charges, and operates only when the computer is turned on. Data written to RAM vanishes when the system is powered off.

Computers are also differentiated by the amount of RAM they contain. The more RAM in the computer, the faster it works, but this is only applicable up to a point: For a slow processor or motherboard, increasing the RAM cannot push performance beyond a point. Most computers currently should come equipped with at least 512 Megabytes (512 million bytes of data) of RAM, though increasingly, advanced software has meant more should be preferred if it is possible. Computers can often take upto 4 Gigabytes of RAM in all, though this is dependent on the motherboard.

The computer has another kind of storage called Read Only Memory (ROM). ROM contains data that is permanently etched onto a chip, and typically stores the commands necessary for a computer to boot up, or start.

Secondary storage devices: Hard disks (HDDs). Floppies and CD
 
In addition to RAM and ROM, computers have secondary storage devices such as floppy discs, hard drives, and CD-ROMs. These devices are responsible for long-term storage of data and software programmes. They can hold much more data than RAM and ROM, and are much less expensive. They are also much slower than the primary storage devices. Data stored in memory can be accessed by the CPU in nanoseconds (a nanosecond is a billionth of a second), while data on a hard drive is accessible in microseconds (a thousandth of a second). This means your hard drive is about a thousand times slower than RAM.

Most modern computers have hard discs capable of storing 120 gigabytes or more of data, with 250 and 500 GB becoming rapidly more common. (A gigabyte or GB equals a thousand megabytes.)

Floppy disc drives use an external storage medium called a floppy disc, which is a small 3.5" square plastic case that contains a magnetic surface. Though comparatively less used nowadays, they are still found on many older systems, especially in small towns and more remote areas.

The graphics/video card and the monitor
 
The video card and monitor allow us to communicate with the computer by seeing what it is actually doing to the data we are giving it. We need to give the computer instructions and data before it can do anything. We then need to see the results of the instructions displayed in a way that we can understand.

The monitor, or screen, works much like a television screen. Like a television, the computer monitor needs a video signal to display a picture. The video card creates this signal by interpreting the data the computer processes. The video card connects to the motherboard and converts the computer's digital output into text or pictures for display on the computer monitor.

Demanding video applications like video editing may require specialized video cards that carry their own memory and execute this process quickly.

Monitors come in several varieties: Cathode Ray Tube (or CRT) monitors are most common - and cheaper - and work exactly the way your TV does. They come in flat screen and normal screen varieties, with flat screen to be preferred because the picture doesn't distort as much at the edges. The other type of monitor is the LCD or Liquid Crystal Display, which are thinner and lighter, but are somewhat poorer in colour rendition.

Monitors are usually 15" or 17" in diagonal screen size - the latter consumes more power - but larger monitors (21", 25") are also available for specific purposes.

Keyboard & Mouse
 
The keyboard and the mouse provide us with a way to input data into the computer, and interact with it. By typing on the keyboard - which is almost exactly like a typewriter keyboard - and pointing and clicking with a mouse, we are able to give instructions to the computer. The instructions are converted to digital data.
Keyboards are usually in English, though specific language keyboards are also available. In many cases, the same keyboard is adapted to type letters of various other languages, a function that is guided by the availability of the font (or typeface file) for that language on the computer.

Mice are available in two button and three button versions, with various functions being accessed by each of the two or three buttons - most functions can be achieved with two. Many modern mice also carry scroll wheels, a small wheel on top which you can use to quickly move up and down on a page displayed on the screen. Older mice have a trackball based design where a small rubber ball at the bottom moves as you move the mouse. Newer mice have an optical input system where a laser reads the surface the mouse is moving on to understand which direction it is moving in (and are hence known as optical mice.)

Sound or Audio cards
 
Adding a sound card to a computer makes it possible for the computer to play and record sound.
The card converts audio signals into a digital format that can be processed by the computer. The card also converts digital audio stored on a computer into a format that can be sent to other equipment such as loudspeakers and the mixing desk.

Sound cards vary enormously in quality and features. In the radio studio the primary purpose of a computer is to play and manipulate sound. Therefore, there are more demands on the studio sound card than on a standard office or home computer. The right choice of sound card used in a studio computer is vital. As the studio sound card tends to be more sophisticated than others'it is also often more expensive. Even basic sound cards today give very good quality audio; but if you intend to connect professional grade microphones directly to the computer, a sound card that has balanced and unbalanced connectors - on the card itself or on an attached break out box - may be a good choice.

Modems and LAN cards
 
Computer communications are becoming a part of everyday life. More and more people are using the internet and e-mail as a resource and as a means of communication. By connecting our computer to a phone line or a network connection, we are able to communicate with other computer users. A modem makes it possible for a computer to communicate through phone lines. Modem is an acronym for Modulator/Demodulator. Modems translate digital computer information into analog signals used over phone lines. They can also work in reverse and translate the analog signal from a phone line into a digital signal used by a computer.


Modems are distinguished by the number of bits per second (Bps) of information that they can transmit. Nowadays, commonly used modems operate at 33 600 and 56 000 bits per second. However, older modems that work at lower speeds are still used in some places.

Like CD-writers, modems can also be internal or external, though it is more usual to find the internal ones today. They need to be connected to the telephone socket using a telephone cord, more usually known as an RJ-11 connector.

If you have more than one computer in your station, you will probably want to share files and resources such as printers amongst them. To achieve this your computer needs networking hardware. This hardware is a network interface card (NIC), often just called a network card or Large Area Network (LAN) card. Most new computers are supplied with a network card. The network card allows the computer to talk with other computers on the network (that is transmit and receive data).

Modems and network cards are more important for the office systems than for any computers based DAWs that you may be installing: Most of the outputs from a DAW are likely to be through the mixer or on a CD, so networking the system is not a priority.

If you have more than two computers that you want to connect together, you may need a network hub to which you connect all of your computers. The hub switches information between the computers.

Other peripheral hardware
 
In addition to the hardware already listed, there is a wide variety of external hardware, often referred to as peripheral devices (or peripherals) that can be connected to a computer. The more common devices are CD-Writers used to make audio and data CDs; printers for printing information onto paper, and scanners to convert text or pictures on paper into a digital format for the computer. Many stations today use CD-Writers and store and distribute programmes they have produced.

It is also useful to have a printer for printing out text reports, letters and other information. Printers can be colour or black and white; and can be inkjet or bubblejet printers; or laser printers. Laser printers tend to be more expensive, but their toner (ink) cartridges tend to last a long time. Inkjet printers are intended for lighter work. They may cost less initially, but often have expensive ink cartridges that over time can cost more than the printer itself.