Voltcraft dso 2020 usb 2 channel 20mhz oscilloscope voltcraft dso 2020 usb p the voltcraft dso 2020 is a usb oscilloscope that is used in combination with a windows reg based computer with a usb 2 0 interface the attachment can be used as a fully digital storage oscilloscope short dso for the visualisation of electric quantities and signals there are two independent input channels available for measurement the probes are connected to the dso via bnc connectors p p operation and disp