Self accelerating reed switch magnet spinner.

[MileHigh]

Synchro1:

I lit a 120 volt LED bulb to about 2/3 the brightness directly from my SSG Bedini output leads, measured by a LUX  meter. I then calculated the output in watts and compared that figure to the input as measured by an analog amp meter. The best recovery ratio I recorded was around half your 30% estimate at 17%. Measuring rise in charge battery voltage is extremely deceptive.

There is a "chicken and egg" issue for Bedini motors.  The average beginner joins the Yahoo Bedini group and uses his source battery to charge the charging battery.  He or she gets all excited when they see the resting voltage go up on the charging battery.  However, they are not aware that the Bedini motor was doing an absolutely miserable job of transferring input power from the source battery to the output power going to the charge battery.  The "radiant spikes" business is all just a psychological deflection scheme to divert your attention away from other things and keep it focused on the "magic spikes."

The "chicken and egg" issue is this:  You get all excited about charging target batteries using your source battery.  But who charges the source battery when it gets depleted?  It's probably usually a battery charger from the mains!  They even tell you to not use one of your recently charged batteries as the source battery.  Something about "you should not use a 'radiantly' charged battery as the source battery."  The real reason is that your "radiantly charged" battery will crap out pretty quickly in its new found role as a source battery - because it only got 30% or less of the energy transferred into it that was in the original source battery.

And the "magic spikes" are not "magic" - in the Yahoo Bedini groups they will not explain to you how a coil works.  Likewise, at the Bedini conferences they will not explain to you how a coil works.  A lot of the people on "Team Bedini" don't even know themselves.  It's just the way it is.

MileHigh

[MileHigh]

I am going to more or less close out the issue of the sense coil with one more example and leave people to ponder some issues.

Let's suppose in TK's rotor the diameter of each of the rotor magnets is one inch.   Let's suppose that we use a sense coil that is large and has the proportions of a large ring.   Suppose the sense coil is three inches inner diameter and 3 1/4 inches outer diameter and and about 1/4 inch deep with lots of turns.

If a sense coil like this is close to the rotor, you will lose that nice steep "zero cross" portion of the waveform at top-dead-center that we have seen in all of TK's screen captures.  There will be a large "dead zone" instead where the waveform is flat or nearly flat.  So you will lose or almost lose your top-dead-center reference, which would not be nice.

Now, with the same ring sense coil, if you moved it a few inches away from the rotor, chances are you would get much better results and you will see a waveform that gives you a very good indication of top-dead-center.

If somebody checked this in real life, my descriptions above might not correspond directly, but they will be close enough.  I am crunching this all in my head.

Anyway, I will leave it to the readers, if they are so inclined, to try to understand why the larger sense coil will act like this.

MileHigh

[TinselKoala]

I put a 10 pF cap from the op-amp sense coil input, to ground. It helped stabilize the thing, since it went all wonky after I rebuilt it mechanically, moving the drive coil over to where it belongs and mounting the circuit boards better. It suffered from the jitters after that, but now with the 10 pF cap all is stable again.

[Magluvin]

Anyway, I will leave it to the readers, if they are so inclined, to try to understand why the larger sense coil will act like this.

MileHigh

Its simple enough to say. Having a 3in inner diameter coil leaves a lot of space where there is no windings for the 1in mags flux to cut and induce current. So you see a positive hump, dead zone, negative hump. Where a coil with a small inner dia, the transition from pos to neg humps is seamless.

But, thats only if the coil is close to the rotor/mag. The further outward from the rotor, the less of a signal, but the dead zone will shrink with distance. Not sure how much signal is needed to trigger here.

Mags

[TinselKoala]

It runs stably at 14 percent duty cycle, 1110 RPM (74 Hz) and the neon is still lighting, not brilliantly but nicely lit. This is as slow as I can get it at the moment. And the Max RPM sweet spot is about 2310 RPM, brilliant neon, and a duty cycle of about 77 percent. The timing varies a bit over the range, it needs to be adjusted for the min and max RPM zones. Easy to do with this setup and the scope!