by: Mary Anne Winslow

Until the creation of Digital TV, television has not had any significant advancement in technology. Today Digital TV is becoming more and more popular in Australia as well as in other developed countries.

Firstly, in order to fully understand the impact of digital television, we must understand how it differs from analogue television. To create a picture on the television, each television receives television signals known as analogue signals. This signal is sent from a transmitter to a translator and then onto your television screen. Interference can be a problem with the signals picking up other signals from equipment such as mobile phones. Interference, known as “Ghosting” is caused by the reception of a direct signal into a delayed reflected signal, creating a ‘snowy’ effect on your screen. A quote from the final report of the Australian Broadcasting Authority Digital Terrestrial Television Specialist Group (1998) explains the different types of interference. “[Over the air] television broadcasting is a demanding engineering challenge. The signals are subject to reflection from and obstruction by buildings and the terrain features. They are subject to interference from sources of electrical noise (e.g. motor vehicle ignition, overhead power lines, electric traction systems, florescent lamps, fax machines and digital mobile telephones and other transmissions). They are also subject to fluctuations in signal strength as they pass through the atmosphere. “Digital television was created with this problem in mind and does not pick up interference thus providing a better, clearer picture. The figure 1 below shows the path in which a signal travels from a transmitter to a translator and how the signals can be delayed and reflected.

. To receive digital television you must purchase a digital set top-box. Similar to an analogue television, digital television receives signals from a transmitter. Standard television uses an analogue waveform to transmit a signal whereas digital television uses a digital signal sequence similar to that of computer code in form as ones and zeros.

Although digital television has a large amount of benefits, there is one pitfall. With analogue television if the screen appears to be snowy when the reception is not spot on, the majority of the time you can put up with a little snow and still watch your program. However, with digital television the digital receiver either recognises the digital data stream or it doesn’t. In other words, you will either get a perfect picture or you will get nothing at all. In some cases ‘pixelation’ may occur. Simons (1998) writes “ pixelation (blocky squares similar to that used to deliberately mask peoples faces on the news.”

The benefits of digital television seem to outweigh the pitfalls. The first one is the wider screen. Digital television will show a wider screen than analogue television creating a more cinematic atmosphere. One of the greatest advantages of digital television is that there is reduced, if any, interference on the screen. This means no white dots or annoying white lines when a storm is approaching or when a neighbour turns on their air conditioning.

Digital television provides better sound quality and pictures than analogue television. This is similar to the idea that people prefer to watch DVDs over videotapes because of the different qualities. You will be able to program your digital television to what you want to watch or tape. Lastly, there will be a variety of channels and views available on different events which analogue television does not provide.

What will be expecting in the future for digital television? Well, it is predicted that by 2008 the analogue television will no longer be available and households all around the world will be connected to digital television. Expanding technology will surely see the expansion of functions available to the digital television.