... 4.with USB interface MCH USB Oscilloscope, DS-2025CA Digital Oscilloscope, 25MHz freq. ,dual channelSpecifications: SpecificationsDS-2025CAChannels2+ ... aEquivalent sample rate50GSa/sInput impedance1MΩ//13pFInput couplingDC, AC, GNDTriggerEdge, video, pulse, delayAcquisition modesAuto, normal, singleTrigger sourcesCH1, CH2, Ext ... DS-2025CA USB Oscilloscope, 25MHz freq.,dual channel digital oscilloscope