Abstract: A signal waveform display system for displaying waveforms of one or two input signals on a display screen is provided which comprises first-third input switching circuits, first and second trigger generators, first and second horizontal sweep generators, and a composite horizontal sweet generator. The trigger generators respectively generates first and second trigger pulses synchronously with the input signals provided thereto through the first and second input switching circuits. The sweep generators are triggered by the trigger pulses and generate first and second sweep signals having variable time periods, respectively. The composite sweep generator generates a composite sweep signal including lower portions of the first sweep signal which are smaller than a reference voltage, and upper portions of the second sweep signal which are higher than the reference voltage.

Abstract: An apparatus for displaying line and frame waveforms having different time-scales of a video signal on a display screen is described which comprises complex sweep signal generating means including a line sweep signal generating circuit 2, a frame sweep signal generating circuit 3 and a switching circuit 4, and horizontal axis drive circuit including a horizontal location arrangement circuit 5 and a horizontal axis drive circuit 6. The line and frame sweep signal generating circuits 2 and 3 generate line and frame sweep signals S.sub.2 and S.sub.3 synchronously with line and frame synchronization signals of the video signal, respectively, and the switching circuit 4 alternatively transfers the line and frame sweep signals S.sub.2 and S.sub.3, synchronously with the frame synchronization signal to generate a complex sweep signal S.sub.4.