you can spend twenty thousand dollars on a used VNA. Around the time Ted’s project began, Rigol released their cheap spectrum analyzer, the DSA815. This thing only cost a thousand dollars.

chunky interfaces we were used to, and even though it was supposed to be unobtrusive, it was hard to tear your eyes off that silky-smooth spectrum analyzer bouncing out your favorite MP3s.

A hardware device or software used to examine the frequency and ... whereas an oscilloscope would show total noise level, a spectrum analyzer would show the noise as related to frequency.