GENERAL ) The 5228 oscilloscope has a bandwidth up to 250 MHz, double timebase and three separate vertical channels. Channels A, B and C can be used separately or simultaneously in the "sweep alternate" or "chopped" mode, and in the algebraic addition mode (A + B). Channel B can be inverted. The double timebase {Bl, B2) provides a choice of the following sweep modes : Bl only, Bl + B2 delayed and extra-bright, B2 delayed only, Bl and B2 mixed, and Bl and B2 alternated. Triggering can be controlled internally from channel A, B or C, line source, or an external signal. Triggering over 250 MHz is also possible. Y mode, X mode and Bl and B2 trigger mode controls are incorporated in a keyboard. LEDs come on to indicate selected functions. Utilization of this keyboard is further improved by the inclusion of two preselected function memories. The oscilloscope also has a digital display, used for measurement of DC voltages applied to a "voltmeter" input, or for display of Adiv vertical offset between the Bl and B2 sweeps ("sweep alternate" mode), or display of the At time interval between any two points of a phenomenon observed on the screen.