Cieszynski J. Closed Circuit Television

Second edition. — Burlington: 2004. — 262 p.The term ‘closed circuit’ refers to the fact that the system is self-contained, the signals only being accessible by equipment within the system. This is
in contrast to ‘broadcast television’, where the signals may be accessed by anyone with the correct receiving equipment. The initial development of television took place during the 1930s, and a number of test transmissions were carried out in Europe and America. In the UK these were from the Crystal Palace transmitter in London. The outbreak of the Second World War brought an abrupt end to much of the television development, although interestingly transmissions continued to be made from occupied Paris using an experimental system operating from the Eiffel Tower; the German propaganda machine was very interested in this new form of media. Ironically, the war was to give television the boost it needed in terms of technology development because in the UK it seemed like every scientist who knew anything about radio transmission and signals was pressed
into the accelerated development programme for radar and radio. Following the war many of these men found themselves in great demand from companies eager to renew the development of television.