@bartsw I’m getting a reading. I don’t remember the numbers. I spread my equipment so the components are at least 3ft away from one another’s power transformers.
If you use that tool and measure around the area where a transformer is in an amp and raise the volume while music is playing, the reading changes as the amp draws more power from the wall and emits more EMI.
I have my components on SolidSteel amp stands. Side by side.
The router and the switch are at least 3 feet away from components.

