Originally Posted By: ConRAD
Furthermore please be careful because in your calculations you considered 28 poles but in the reality you must consider them as 14 “couples of poles” since you need a couple N-S to produce an hertz and not just a single pole

Ups, sorry, my typical back-of-the-envelope mistake.

I see an Vpp of around 25V on your oscilloscope, so the 6V amplifier setting is the next big no-go? He is limiting to 21V anyhow and probably wasting addition energy that way. Now i understand the need for a metal heatsink.