The resonance of ferrite winds up being very useful in ultrasonic cleaners in that it allows a higher level of energy transfer than would be available at a nonresonant frequency. Some disk capacitors exhibit a similar ringing due to a piezoelectric effect.
Frequencies are often times found in circuits where most would not expect it.
I deal with RF Amplifiers, and we have one circuit that uses a simple ferrite that is rectangular with a 75-ohm strip of wire through the center of it. As we increase the power out of the amplifier, the ferrites literally sing. Albiet this is slightly a different cause than the article, it is an interesting phenomenon that can be found in many places.
By the way, what was ever done to completely remove the ringing, or was the epoxy solution the final one?
New versions of BASF's Ecovio line are both compostable and designed for either injection molding or thermoforming. These combinations are becoming more common for the single-use bioplastics used in food service and food packaging applications, but are still not widely available.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This radio show will show what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.