Full Title

Control arrangements or circuits, of interest only in connection with cathode-ray tube indicators; (cathode-ray oscilloscopes G01R13/20; ) > using single beam tubes (G09G1/26, G09G1/28 take precedence), > the beam tracing a pattern independent of the information to be displayed, this latter determining the parts of the pattern rendered respectively visible and invisible > the pattern of rectangular co-ordinates extending over the whole area of the screen, i.e. television type raster