om point to point communications to other forms of radio links, and it is not possible to mention them all. There has been a vast amount of investment needed to achieve the high standards of communication needed today. Satellites, microwave links, cellular phone base stations, sophisticated radio data links are but a few that are needed to support today's requirements. To achieve this a number of different types of technology are needed: antennas, trans- mitters, and receivers as well as several other items are all needed to make up the complete system. This provides a great amount of variety for anyone looking to take radio up as a career or hobby. Before looking at the emerging technologies and where radio technol- ogy is moving, it is always worth having a look at how radio technology arrived at where it is today. In this way it is possible to understand some of the reasons why it is structured and organized in the way it is. The story of the development is fascinating and the very earliest discoveries of major importance can be traced back thousands of years. The story of radio The very first discoveries of interest in this story can be traced back to the ancient Greeks and Chinese who investigated the properties of lodestone, a magnetic oxide of iron. In fact the Chinese are often credited with the invention of the magnetic compass. Knowledge of this discovery spread over the known globe and eventually it reached Europe. Here the Greeks with their well-developed society paid most attention to it. Another early discovery of major importance was that when amber was rubbed against another material, it attracted other objects towards it. This phenomenon possibly added value to the stone when it was traded. These were only basic discoveries and very little was understood about them. It took many hundreds of years before people started to make any progress. One of the first people to make anything of these phenomena was William Gilbert, the physician to Queen Elizabeth I of England. He performed a vast number of e