Thanks Mags,
So, do you think Raymond's mechanical oscillation frequency is the same as his coils resonant frequency? That's the only thing I can't check. The coil would need an insane amount of turns (with no cap) to resonate at the low mechanical frequency! Do you think that's why his coils dc resistance is 350 Ohms?
Good luck and report what you find good or bad.
Regards Luc
When I did some stuff with pulse motors that spun up to the resonant freq of the coil(and cap. large coil.) the rotor wanted to stick at that rpm. If you drive the rotor past that point, then it will accelerate onward.Had to deal with reed switches reaching their resonance also. So changing the cap would allow me to see that the LC held the rotor to a locked freq of rotation. As long as the LC freq is steady, so will the rpms be steady. Well pretty much depending on load characteristics. I was thinking earlier that the lobing motor cam axial and the physical connection to the coil were hopefully of decent tolerance and strong enough for all of that physical happening going on, but there may be discrepancies we cant see from afar. His leds, if connected parallel but opposing polarity, say red led, 20ma, 2v at full power, then maybe a 100ohm coil and maybe 40mw P-P? . If in same polarity, 80mw . If in series then maybe a 200ohm coil, 80mw. Just possible guess. He wasnt smoking leds. So we have to think, is 80mw enough to affect that moving system enough to cause what is happening? More info to clarify if there is any magnetic hardware near the coil on the arm. Would need to try different motor rpms and test to eliminate any resonant effects that may be causing the result. Mike may be right. cant say unless its made the way the guy set it up, or we will need to try with and without mechanical resonance. Has anyone asked him to come to the forum? Mags
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