At a minimum, if plugging it in to a device and measuring waveforms is good enough for your application, you need an oscilloscope with 10 GHz bandwidth or so (d

At a minimum, if plugging it in to a device and measuring waveforms is good enough for your application, you need an oscilloscope with 10 GHz bandwidth or so (don't quote me on that, I don't remember the max speed used by USB). Scopes at that level require a whole lot of R&D and very expensive components so they're really not something you'd want to buy to check your own cables. If you're talking about reading the e-marker then you can just plug it in to a device and use an app. Google will help you find one for your platform.