Variable Frequency Drive for a larger factory fan

[chy_farm]

Does the breadboard not contribute to rf noise ?Once the design goes to PCB there should not be so much interference.

Trigger, I tried to recall my memory and some data on this, and here found a pic showing comparison between the two, before shield and after shield.
Either case bread boards were already replaced with universal boards.


Although the carrier wave was not very stable, I know the reason that the center common level was a tad off-set. the thicknesses of the sine waves tell the shield shows effect on it.

This tell us that even PCB board wants some means for cutting noise.

Chy