Abstract: Apparatus for use in conjunction with a television broadcast receiver for storing, in a main memory, digital data transmitted during portions of the transmitted video signals not used for picture signal content. The digital data is extracted at the receiver at a high data rate and stored in the main memory. The stored data may be used, under viewer control, to generate a character display on the display tube of the receiver. Alternatively, the data content of the main store may be written into a first buffer store from which data is read out at a slow rate and stored by a low frequency signal recorder. Data signals may subsequently be read out from that recorder (or from a separate recorder on which suitable data signals have independently been recorded) into a second buffer store from which they are inputted at a high data rate into the main memory for generation of a display.