A television monitor display comprises a first selectable source (100) of a first video display signal (OAM) and a second selectable source (U13) of a second signal (OSD) for video display. A video processor (U2) receives signals from the first and second selectable sources and controllably combines the second signal (OSD) with said first video display signal (OAM). A sync separator (U3) is coupled to receive the combined signal and generate therefrom separated synchronizing signals (HSYNC, VSYNC). A controller (U8) is responsive to user selection of the first selectable source (100) and generates a disable signal (FSW DIS.) for controlling the video processor (U2) to inhibit combing of the second signal (OSD) for a predetermined time.