@ClaraListensprechen@universeodon.com @PeeBeeJayBee @Ralph058 @SrRochardBunson @sergio_101 @LGsMom Yep or SAW filters. To me those are not electronic. Even though they might contain active preamps, they are passive electromechanical devices. Same with a quartz crystal. Passive.

But yeah, there are edge cases where one can quibble.