I haven't been making much progress on my Hendershot build so I've been looking at other systems and how they may apply to the Hendershot generator. I've run across some info that, IMO, ties it to the Floyd Sweet Vacuum Triode Amplifier (VTA). It wasn't apparent at first from the Hendershot documentation but the magnetic field in the armature ties to the "conditioned" magnets in the VTA. In
another thread on this forum I showed why the radar magnetron was important. It has 3 poles, the outer 2 of one polarity and the center one the opposite polarity. Why that is important has just come to me while looking at the VTA info.
The center pole of the magnatron magnet is physically further away from the plane of the outer poles to allow for the installation of the radar tube. What this does is make that center pole's field weaker on the armature. We don't see that when we use a steel armature but it is very clear using a Permalloy or HyMu80 armature. This weakened area is what made me think of this thread.
In the VTA documentation they call this weakened area in the center of the magnetic field a "magnetic bubble" and this is what you are creating in the "polymagnets", although you are creating multiple "bubbles" rather than just one.
Here's an interesting paragraph from one of the sites I found relating to the bubble. He is using ring magnets. "The bubble is created in the magnet as a result of partial demagnetization. By doing this, I am moving the Bloc wall and magnetic poles 90 degrees from their original position. After the field is modified, the north pole is now orientated towards the center of the magnet, and the south pole is along the outer edge of the magnet. When the band [Bloch wall] is centered between the outer circumference and the inner, the magnet is at its weakest point and the poles flip very easily.
Running a 60 Hz AC signal running through a small electromagnet at a 90 degree angle to the magnet face makes the poles flip-flop, and the magnetic bubble expands and contracts, back and forth." The following link is about Sweet's "Space Quanta Modulator" (SQM) which was the precursor to the VTA and contains the above quoted text. Search down to "magnetic bubbles".
Sweet SQMIt's the highlighted part that caught my attention. To gather electricity from a magnet we need a changing magnetic field and he is saying that we can flip the polarity of the domains which is a changing magnetic field. I'm thinking that a small signal applied in just the right place on the magnet changes the polarity and the polarity change feeds a stronger change back to the electromagnet that overrides the initiating change. The Hendershot buzzer coils are at right angles to the armature and the juxtaposition of the center pole's field to the outer poles' fields creates the magnetic bubble in the armature.
The "secret " to Sweet's VTA is said to be the "magnet conditioning" and I'm thinking this magnetic bubble is the "conditioning". The following link is to a video from some people that have apparently replicated Sweet's VTA although they had poor results. The first guy says he got it working but only for a minute or so. The interesting part, however, is how they conditioned the magnets. They didn't do it in one huge pulse like you are doing but in a continuing pulse train using the frequency they wish to obtain from the conditioned magnet. They used 60 Hz with the electromagnetic conditioning pulse being applied at the zero crossing point of the AC signal. The good part about that is you can do the pulses without destroying your magnetizing device. They also say the method can be applied to the same magnet many times.
Successful Replications of Floyd Sweet's VTASQM as Hendershot generator
Did you ever do anything with the higher power magnetiser?