High Density Digital Recording with Video Techniques

Abstract

A digital recorder which writes or reads digital data at 8 megabits per second and has a storage capacity of 84 billion bits per reel of tape is described. The packing density is in excess of I million bits per square inch on conventional one-inch magnetic tape. The high packing density and transfer rate was achieved through the combination of phase-encoded digital electronics with a helical scan video transport. The use of the helical scan technique permitted extremely efficient utilization of the tape and permitted inclusion of other features, such as high-speed search (400 ips), individually addressable records, and self-threading and cartridge-loading capability.