Wave Detector
Hold it to see waves. The corner of the screen shows the spectrum, the strongest sources with the power a tuned machine would get where you stand, and outlines the sources, even through walls.
Look at a machine to see what it listens to, how much power it gets of what it needs, and a hint: “Tune to G#3 +15 ct to get about 6 W”. If nothing reaches it, it says so.
The first detector hears the audible band within 16 blocks.
Wave Detector II hears every band within 64 blocks. Right click opens the full screen: the three spectra, every source (click one to make it pulse in the world) and, for the machine you looked at, each source: what it gives now and what it would give once tuned. Aimed at a pipe or a machine on a line it reads the line: its tone and gear, its sources and machines, what runs through that pipe.