I could generalise it as anything with fast rise times. A 74lvc14 can kick out a 400ps edge even if you clock it at 1Hz for example. That's got quite some harmo

I could generalise it as anything with fast rise times. A 74lvc14 can kick out a 400ps edge even if you clock it at 1Hz for example. That's got quite some harmonic energy. Also it's usually the really slow stuff I have that oscillates madly :(