30% of conducted and radiated EMC problems are caused by EMC filter resonances, would you agree?

[treez]

Would you agree with this generally?
People underdamp EMC filters because they dont want to introduce losses.
But then they end up with unavoidable filter resonances.
They simply tolerate these, and try and push them (the resonances) into low energy regions of the radio spectrum so that they can get an overall pass?

 

[dick_freebird]

I have no reason to agree with it being specifically 30%.

I'm no magnetics expert but I'd think an EMI filter
would be made with lossy (esp. HF) magnetic materials
so that DC / line frequency sees no losses but RF does.
Like ferrite beads are different material than power
toroid cores for >100kHz, right?

But whether this is true, or relevant, I couldn't say.

You could de-Q a filter in ways other than series
resistance.

 

[KlausST]

Hi,

The same is with me.

... with HF lossy materials.

To dampen the resonance of an LC ... I often use a series-RC in parallel to the filter-C.

Klaus