Abstract: A method of error-free, simple programming of a data decoder for the purpose of recording desired data programs is achieved when a data guide table, generated at the transmitter end, for programming the recording, and a data status table for signaling the data programs currently running are evaluated. In addition to date, time, broadcasting company, identifying number and length of the files, the data guide table contains information on the hardware and software configurations, which is required for receiving, for decoding and for outputting the desired data program, and further information for automatically reloading software possibly missing at the receiver end. In this way, it is possible as early as during programming of a data program to carry out a check of the system configuration required at the receiver end and to output an error message or warning to the user if his own system is not suitable for receiving, decoding or outputting the desired data program.

Abstract: In order to increase decoding safety of the address frame of a teletext page during the reception of teletext data, and in particular of a page containing higher level supplementary data, without having to apply additional error control steps, the address frame for a teletext row is forecast from the decoded material, and if required, with a corrected address frame of the preceding teletext row. The forecast address frame is compared with the actually received address frame of the succeeding teletext row. If a deviation at two or more information units of a byte are detected during the comparison, and if required during decoding of the received address frame, the forecast address frame is used instead of the received address frame for addressing the data stream of the concerned teletext row.

Abstract: A data stream is separated from a television signal during the reception of data transmitted in the television signal. The data associated with a given page are collected. The pages thus assembled are temporarily stored. One or more separated pages with lists are transmitted and processed by the decoder at the receiver. Images and image sequences, if necessary, together with a text page, are displayed and sounds are reproduced using circuitry, such as the image and sound decoders, respectively, that already exist in a receiver compatible with digital signal transmission. A given separate page, referred to as the text-image-sound link table, contains addressing information and corresponding codes for image and/or sound data which are in the data stream. The separate page also contains search words and the text page numbers associated with the search words. When a specifically highlighted search word is selected by the user in a selected text page, a selection process is initialized.

Abstract: In order to achieve a greater degree of security in the decoder for the control frame of teletext pages, the control frame is initially selected and decoded from the data stream by means of a bit by bit comparison with a frame word. Thereby, the following steps are carried out in dependence on the number of coincidences occurring during the bit by bit comparison with the frame word:a) if, during the bit by bit comparison, eight coincidences are detected, the control frame is considered to have been identified and the counter is reset;b) if less than eight coincidences are detected, it is determined whether a particular number ("444") or a multiple of this number ("n 444") has been reached on the basis of the count-state of the clock pulse counter, whereby, in the event that this number has been reached, the control frame is considered to have been identified and the counter is reset.

Abstract: In order to compatibly transmit teletext data in the form of special characters, fine textures and color hues at higher WST levels, complementary data in the form of one or more associated complementary pages are transmitted for each page of teletext by the broadcaster in addition to the basic teletext data of conventionally structured teletext pages (level 1). The complementary data for some or all teletext pages are transmitted preferably in at least one complementary page. In the receiver, the complementary page(s) associated with a selected teletext page are temporarily stored separately from the corresponding teletext page(s) and processed so that the characters associated with the basic data are displayed in those character positions where there is no complementary data present. The characters associated with the basic data in cooperation with the complementary data are displayed in those character positions where complementary data is present.