Abstract: An indicator is described for alerting a television viewer to the fact that a teletext signal is being received. In the preferred embodiment, the indicator includes a control which senses the detection of the framing code associated with the received teletext signal to actuate an indicator lamp.

Abstract: A teletext communications system includes a transmitter cyclically transmitting a plurality of conventional teletext encoded data rows together with one or more teletext encoded special services data rows. A plurality of teletext decoder equipped receivers are operable for acquiring the conventional teletext rows but not the special services rows. Subscribers to the special services data are provided with data decoders responsive to the cyclical transmissions for acquiring only the special services data rows, the data decoders including apparatus for storing the data encoded in an acquired special services data row and for providing a display of the information represented thereby.

Abstract: A teletext communications system comprises a transmitter, e.g. an orbiting satellite, transmitting multiple pages of a teletext encoded data service at selected times of the day, each teletext page including a first non-displayable auxiliary teletext data row defining a selected time interval and a unique page memory address code. The transmitter also continuously transmits a second non-displayable auxiliary teletext data row including a time of day code. A teletext decoder is adapted for acquiring and storing each transmitted teletext page at a page memory defined by said page memory address code and automatically rebroadcasts each of the stored pages for which the stored selected time interval coincides with the transmitted time of day code.

Abstract: A color control circuit for selectively modifying the red, green and blue color signals developed at the output of a teletext-type decoder comprises a common input stage responsive to the teletext decoder for developing a bi-level control voltage identifying the portions of the color signals representing background and foreground display information. Each color signal is coupled to a respective output stage which causes the associated color signal to assume a first intensity level in response to the control voltage being at its first level and a second intensity level greater than the first intensity level in response to the control voltage being at its second level. As a result, background colors are displayed at a reduced contrast level relative to foreground colors. In addition, selected single color foreground information may be displayed at a further increased intensity level to improve the readability of the display.