In short, [Christer] needed a high-frequency active differential oscilloscope probe, and they’re not cheap. So he built one himself. With some minor tweaking on the input damping resistors ...

If you have a single-ended signal and you want to view it on your scope, your choice is either a passive or active probe. Usually some kind of passive probe will be most available. These commonly ...

Identity of the active species. A quality chemical probe has sufficient chemical and physical property data to permit utilization in in vitro and cell-based assays with interpretations of results ...

It is an active criminal probe, according to the MPD. Mills’s office told The Hill in an emailed statement Friday that “law enforcement was asked to resolve a private matter at Congressman ...