PREFACE T IS the purpose of these two Manuals on BASIC SYNCHROS AND SERVOMECHANISMS to describe and illustrate, in the simplest possible way, the fundamental characteristics of two groups of devices which are not only used in many types of military equipment, but which are also essential components in what will assuredly be one of the most revolutionary industrial techniques of the second half of the 20th century. Automatic process control-automation, to use its more popular name-is an outgrowth of the technical advances made in military equipment during the Second World War. It is far more than the mere regrouping of existing machines, which is what many people believe it to be. It is a radically new concept. The idea of mechanization implies a set of mechanical devices carrying out a series of motions-pre-determined, accurate, and continuous as long as power is supplied-but lacking any ability to modify their own behaviour if conditions begin to vary. Automation, on the other hand, implies a built-in brain-systemn-however rudimentary-in a robot-like plant capable not only of performing mechanical operations, but also of adapting the initial instructions it has been given in the light of changes which it observes to be occurring in the conditions of its own operation. The control devices of an automated system have four main functions to fulfil. They must detect changes in conditions as they occur they must report these changes to the brain they must decide what corrections are needed to carry out, in the changed conditions, the basic instructions they have been given and they must command that the necessary action be taken by the muscles, or operating elements of the system. All these decisions and actions must be taken and performed within a minutely short space of time-much faster than any human intelligence could possibly achieve. It is with the electrical and electronic devices which detect and report changes in operating conditions as they occur, and which decide upon and issue the necessary instructions to compensate for these changes, that these two Manuals on BASIC SYNCHROS AND SER VOMECHANZSMS deal. THE SYNCHROSERVO Manuals themselves, however, are only a part of a larger design. The unique COMMON-CORE Series of Illustrated Training Manuals, which was developed some years ago at the request of the United States Navy by the distinguished New York firm of technical education consultants and graphiological engineers, VAN VALKENBURGH NOOGER NEVILLE, INC. opens with eleven Manuals covering the fundamentals of Electricity and Electronics BASIC ELECTRICITY, in 5 Parts BASIC ELECTRONICS, in 6 Parts. Together with the two S YNCHROISERVO Manuals, these volumes have all become standard text-books in U.S. Navy Training Schools. Well over 150,000 men have studied them as part of their training to technician level in 14 different Navy trades-and their average training time has been cut by half. Late in 1957, negotiations were opened for a British and Commonwealth edition of the COMMON-CORE Manuals. While they were in progress, it came to the knowledge of the British Publishers that there was working, at the school of Electronic Engineering of the ROYAL ELECTRICAL AND MECHANICAL ENGINEERS at Arborfield in Berkshire, a special Electronics Training Investigation Team whose task was to devise solutions for some of the training problems which would face the British Army when National Service ended, and when the Armys increasingly elaborate electrical and electronic gear would have to be manned and serviced by recruits entering the Army with none of the technical knowledge which many National Servicemen had hitherto brought with them into the Forces...