Fnirsi - Is Fnirsi Oscilloscope Good?

This is a really neat little oscilloscope that's well worth the money. It behaves like advertised. The internal signal generator can only create 10MHz sine and max. 2 MHz square waves.

What does a digital oscilloscope do?

An oscilloscope is an instrument that graphically displays electrical signals and shows how those signals change over time. Engineers use oscilloscopes to measure electrical phenomena and quickly test, verify, and debug their circuit designs.