THE HISTORY OF TELECOMMUNICATIONS According to UNESCO statistics, in 1997, there were billion radio receivers in nearly 200 countries. The figure for television was billion receivers. During the same year, it was reported that there were 822 million main telephone lines in use world-wide. The number of host computers on the Internet was estimated to be million [1]. In addition to this, the military in every country has its own communication network which is usually much more technically sophisticated than the civilian network. . | Telecommunication Circuit Design Second Edition. Patrick D. van der Puije Copyright 2002 John Wiley Sons Inc. ISBNs 0-471-41542-1 Hardback 0-471-22153-8 Electronic 1 THE HISTORY OF TELECOMMUNICATIONS INTRODUCTION According to UNESCO statistics in 1997 there were billion radio receivers in nearly 200 countries. The figure for television was billion receivers. During the same year it was reported that there were 822 million main telephone lines in use world-wide. The number of host computers on the Internet was estimated to be million 1 . In addition to this the military in every country has its own communication network which is usually much more technically sophisticated than the civilian network. These numbers look very impressive when one recalls that electrical telecommunication is barely 150 years old. One can well imagine the number of people employed in the design manufacture maintenance and operation of this vast telecommunication system. TELECOMMUNICATION BEFORE THE ELECTRIC TELEGRAPH The need to send information from one geographic location to another with the minimum of delay has been a quest as old as human history. Galloping horses carrier pigeons and other animals have been recruited to speed up the rate of information delivery. The world s navies used semaphore for ship-to-ship as well as from ship-to-shore communication. This could be done only in clear daylight and over a distance of only a few kilometres. The preferred method for sending messages over land was the use of beacons lighting a fire on a hill for example. The content of the message was severely restricted since the sender and receiver had to have previously agreed on the meaning of the signal. For example the lighting of a beacon on a particular hill may inform one s allies that the enemy was approaching from the north say. In 1792 the French Legislative Assembly approved funding for the demonstration of a 35 km visual telegraphic system. This was essentially 1 2 .
