PURPOSE: To make it possible to display a large amount of digital informations along with radar video informations, by displaying radar video informations by a PPI display system and digital informations by a television raster system in a time division manner.

CONSTITUTION: Radar video input signals RVI are successively stored in a temporarily storing memory 1 in a real-time system and a vertical return wire synchronous signal VSYNC of a television raster is inputted to the memory 1 while radar video output signals RVO are continuously read at a high speed from the memory 1 during the vertical period of the television raster. Because the repeating frequency of a usual radar video is about 360Hz and the repeating frequency of the television raster is 60Hz, the radar video corresponding to 60Hz is displayed on a display apparatus 3 during the generation of the signals VSYNC through a video changeover switch 2. The switch 2 changes over the video displayed on the apparatus 3 by the signals VSYNC. During a period other than the vertical return wire period of the television raster, digital signals DV converted to a television raster system are displayed on the apparatus 3 through the switch 2.