What about the homopolar generator?
Sometimes it can be quite hard to see just where the current loop is. Faraday discovered that if you turn a conducting disk in a magnetic field you can measure a voltage between the shaft of the disk and its rim.  This device, the homopolar generator and its equivalent, the homopolar motorhave been baffling people ever since.

Consider a disk which is rotating in a uniform magnetic field.  The field passes through the disk at right angles to its surface.  Any radius of that disk is moving through the field.  The parts of the radius near the shaft are moving slowly and the parts near the rim are moving quickly but they are all moving in the same direction so the voltages generates by each little bit of the radius all add up.  The result is a voltage all round the rim of the disk which is higher than the voltage at the center.

If you mount a sliding contact at any point on the rim you can measure this voltage.  It won't be a large voltage since only a single conductor is moving through the field and parts of it are not moving at the full speed. Suppose you had a copper disk 20 cm (8") in diameter, turning at 10,000 revolutions per minute, and that you could put it in a uniform 0.1 weber field.  (This would be a very dangerous thing to try!)  The rim will be moving at 105 m/s so the mean velocity of a radius is half that.  The length of the radius is 0.1 meters and the field is 0.1 webers so the voltage will be 0.52 Volts, about a third of what you'd get from an alkaline cell!
If your disk had a low resistance, and if the brush contact and the external circuit also had a low resistance, then quite a substantial current would flow from the shaft to the rim.  Because the voltage is generated on all radii of the disk you could put brushes all round the rim and reduce the effective generator resistance.  Unfortunately the frictional forces on the edge of the rim chew up a lot of input power.  As in any other generator, the motion of the disk is resisted by the force which the magnetic field exerts on the output current.  Thus homopolar generators are only useful if you need a high current at a low voltage and don't care how much energy it takes to turn the disk.
As a footnote, I mentioned using a uniform magnetic field.  You might think that having a field just between the shaft and the point on the rim where the brush is placed would be more efficient.  Unfortunately, when the field is not uniform over the whole disk local currents are generated in the disk, heating it up and wasting input power.  This "eddy-current" effect is the basis of the magnetic brake.  Electricity meters are one common application and some car speedometers also depend on this effect.
  The homopolar motor
If you pump a huge current into the disk the magnetic field will generate enough force on it to make it rotate despite the brush friction. (Early experimenters made contact to the rim of the disk by making it pass through pools of mercury.  Since mercury vapor is rather poisonous this is not done any more.) Unfortunately, generating large direct currents at low voltages is a notoriously inefficient process.  AC can be transformed down to get a low voltage but the rectifying device needed to convert the output to DC tends to drop about half a volt, making the efficiency less than 50% before you start moving anything.  About the only device which can generate large currents at low voltages at all efficiently is, you guessed it, a homopolar generator.

http://phact.org/e/z/freewire.htm

Anyway - homopolar machines are devilishly interesting things
regards,
khabe

Devilishly interesting things indeed! I´ve read all I can find, there isn´t lots of info out there about the N machine. It´s as if the magnets coax the aether to produce some kind of lined up stationary field which then interacts with the conducting cylinder somehow causing the electrons to act much more massive and succumb to the centrifugal forces.

The following facts scream to me that something good is going on:
Back torque doesn´t increase as it´s electrically loaded.
Generating conductor does not cut flux gradients.
Its a one way process. (wont act as a motor when current is applied)

One idea I´ve had that would use an N machine is this:

Make a griggs hydrosonic pump, but instead of having a solid spinning cylinder make the cylinder out of thickish copper disks sandwiched between thickish axially polarised neo disks. Maybe 3 coppers with 2 neos in middle. Now machine the outer edge of the coppers for the cavitation holes just like a regular griggs. Could also optionally machine outer edges of neos if you use oil lubricated grinding tools.

Insulate the end faces of the sandwich using epoxy based marine paint, make sure the copper faces are nicely roughed up using fine grit emery before painting.

Make sure the shaft is well electrically connected to the outer casing, may need hefty brushes for this, Brush cooling will be enhanced by the fact that they are immersed.

Now fill the pump using water with a good amount of electrolyte in it and spin her up.

This should produce good heat from the cavitation alone but also lots more heat as a very high current will also flow between the cylinder and the drum wall, the stronger the electrolyte the higher the current. What´s more the friction of the power take off using water and electrolyte will be just the usual friction encountered in a griggs machine, the extra heat produced electrically will be for free!

All conducting surfaces in contact with the electrolyte  may need to be coated or sputtered with graphite or some other inert conductor to prevent ion migration for a long life.

Maybe a house could be heated very cheaply by filling its radiator system with electrolyte and then running a good sized one of these using a rotoverted motor.

If the diameter or speed or both is increased enough then a high enough voltage could be produced for electrolysis to take place, coupled with the cavitation it may produce interesting HHO yields, but then maybe the HHO will recombine if its ignited by the cavitation recompression and thus just give more heat. So if electrolysis is the main goal then maybe better to do away with the griggs bit.

I may get hold of some neo disks with holes in the centre to mount on a fast motor and start playing, no griggs to start with just an electrolyte heater, It would be an easy way to check for OU in the system because you could just insulate the whole thing and then do simple calorimetry while monitoring the motor power.

Yucca.

What ever happened to the N-machines. Ages ago when Bruce DePalma lived in Santa Barbara I used to periodically visit him. Wow, what a beautiful home he had on the coast!  He was a very nice person. He showed me all of his N-machines, some incredible large. Anyhow, I used to have several of his reports that showed "free energy," and also Dr. Tewari's reports on his versions showed the same results. Has anyone here tried to replicate the fascinating N-machine?

PL

Quote from: PaulLowrance on January 08, 2009, 03:59:20 PM
What ever happened to the N-machines. Ages ago when Bruce DePalma lived in Santa Barbara I used to periodically visit him. Wow, what a beautiful home he had on the coast!  He was a very nice person. He showed me all of his N-machines, some incredible large. Anyhow, I used to have several of his reports that showed "free energy," and also Dr. Tewari's reports on his versions showed the same results. Has anyone here tried to replicate the fascinating N-machine?

PL

@Paul,
It´s great that you met Bruce De Palma in person. I´d like to see and hear about replications and experiments with his N machine too. The reports you speak of, are they available on the net or where they papers he gave you?

I think many are tending to overlook the machine because they think, oh it´s just a normal homopolar generator, but it´s not. The fact that it generates any juice at all is quite weird when you consider no mag flux is being cut. The electrons just seem to be being thrown out of the disc due to centrifugal force??

@All
I´ve ordered some 40mm diameter neo discs with small center holes in, I plan on making a mini N machine using these,some 50mm diam washers and a high speed high efficiency model plane motor I have.

I´m thinking If I run this at speed in a body of strong electrolyte then resistive heating of the solution may occur and calorimetry can be employed to check COP. Can also vary electrolyte strength and so easily check the motor behaviour for backdrag under different output loads.

Fraser.

Quote@Paul,
It´s great that you met Bruce De Palma in person. I´d like to see and hear about replications and experiments with his N machine too. The reports you speak of, are they available on the net or where they papers he gave you?

It's a thick booklet that DePalma gave me. Never seen it online, but Rex Research has some of it,

Dr. Tewari
http://rexresearch.com/tewari/tewari.htm

Bruce DePalma
http://rexresearch.com/depalma/depalma.htm

What intrigues me perhaps the most about DePalma's work is his detailed experiments on Gravity and spinning balls. They are fascinating!  DePalma once told me that a skeptic scientist was replicating his spinning ball experiment in a vacuum, that he completed the experiment, but never told DePalma the results. DePalma did all kinds of fascinating experiments, even with slow turning disc (record player) underneath a potted plant. The plants would grow at an angle.

You know, I just did a youtube search and see nothing on Bruce DePalma's work. Such a shame! He had two huge high rpm highly balanced gyros that showed highly unusual inertia effects. I don't even see a single photo of these machines online. I'm wondering if Andrew (his living partner) has any of these photos.

PL