The advent of digital storage oscilloscopes or DSO’s facilitates the frequency response measurements discussed in the last section. With a conventional scope, the generator’s sweep rate must be kept fast enough to avoid flicker, but slow enough to provide at least a few cycles at the low end of the sweep. A DSO can be set up to trigger on a single cycle of a relatively slow GCV waveform. This permits a sweep through the desired frequency range that is slow enough to permit adequate response of the circuit under test for all frequencies in the sweep. Many DSO’s permit downloading of their stored display to computers, printers, etc. permitting a permanent record of the test.