Hi Jones. Yes, coils have multiple resonances, although generally speaking you'll see a fundamental resonance predicated on the lumped value of the distributed capacity and inductance of the coil. This is why top loading of a coil with a capacity can change the overall resonance, to a point.
Stephen is right, PC board traces are strip transmission lines whose wavespeed is determined primarily by the PC board dielectric. Permittivity is about 3 or 4, you can figure the speed to be roughly proportionate to the inverse square root of that. I know very little about Scott Mckie, but I suspect that may be a good thing (grin). K. -----Original Message----- From: Jones Beene [mailto:[EMAIL PROTECTED] Sent: Wednesday, December 08, 2004 10:05 AM To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: Re: Fast-food for thought Keith Nagel writes, > Yep, that's it exactly. The resonator has two modes, an inductive > slow wave mode and a capacitive fast wave mode. The capacitive > coupling permits energy to travel directly along the axis of > the coil, which means the coil is a true resonator rather than a simple > inductor. The implication being that the coil might have two overlapping resonant modes, which could be partially self-canceling unless one was careful to make the ratio between the fast mode and slow mode into an integer multiple.... Which task is not exactly a simple matter... as Stephen Lawrence points out, especially since the magnet wire in these coils is small dia and may have a varnish of imprecise thickness, so that the refractive index may not even be consistent enough to be published. Maybe that's why so many people have failed to get Scott McKie's tank circuit device to work as claimed....? Jones
