Ultrafax

An experimental high-speed system of record communication known as Ultrafax is described. It is a facsimile transmission method capable of operating at speeds of over a million words per minute. Electronic scanning and many of the other techniques of television are employed. At the sending terminal a flying-spot kinescope using a single-line sweep scans copy previously recorded on photographic film. A 7,000 Mc/s radio-relay system of bandwidth 4 to 6 Mc/s has been employed for transmission tests. At the receiving terminal a second projection kinescope is modulated in intensity by the received video wave. This film is then rapidly developed in a film-processing apparatus with a total delay of less than 45 seconds. System tests over microwave circuits up to 28 miles in length have given speeds of 500,000 words per minute of adequate commercial quality. This is 60 to 100 times as fast as is possible in mechanical facsimile systems currently used.