A high-speed tape reader

At speeds of 1,000 characters / sec, photo-electric sensing of the information is essential and the mechanical control of the tape should be as simple and as free from inertial forces as possible. An electro-magnetic brake and clutch are operated from a photo-transistor sensing the position of the sprocket hole to locate the tape in the reading positions. The action of the brake is virtually free from inertia and the tape can be stopped on any character from the maximum speed. The functional elements, the clutch, brake and photo-sensing head have been designed to be completely interchangeable in the production models which are also fitted with adjustable guide rollers for 5, 6, 7 and 8-hole tape. The optical system permits accurate reading of tape on which the holes are incorrectly positioned relative to the edge. Functional tests show that the accuracy and reliability of the reader in service is of a very high order. Over 106 characters have been read from standard pattern loops without detecting an error.