By Pedro Barros, Barros & Associates Ltd. & John Lopinto, Time Video Information Services Inc.
Time selected full channel over VBI teletext on the basis of technical and business considerations. Full channel provides the tools for a very extensive service, and the support for insertion at the local level without interference with the national component of the service. Content is managed by the editorial staff, using the concept of magazine as a logical group of related material. Access times are adjustable separately for each magazine.
The editorial tools provide for effective integration of written material and graphics, with automated input sources and a computer archive of reference material.
Telesoftware is used as an integral part of the editorial content, and designed to promote system interactivity with the user. Time's leading role includes the development of new encoding techniques for telesoftware and microprocessor operating environment.
Insertion into the video signal is provided by a specially designed inserter, based on dual microprocessors, under control of the master editorial host computer. Transmission to the local markets is achieved via satellite and full video NABTS. Current design of cable networks is adequate for teletext distribution provided proper maintenance is maintained.
A low cost decoder is being developed, which will support both VBI and full channel, and in addition will be capable of running telesoftware. Ultimately, the acceptable configuration of teletext will be determined by the consumer's perception of value, and the economics of the CATV industry.