Tesla and wireless power

Suppose you built a high-freq, high-volt, low-current power supply which ccould drive impedance-matched devices using a single conductor. Does it not make sense that you could connect this "single conductor" to the Earth itself, and therefore operate many distant grounded devices? :)

In practice it only works if you supply each distant load with an infinite-Q tank circuit. I suppose a 1 : 10^20 step down transformer would also suffice. But no progress will endure unless you first take care to destroy your own sexuality and thereby avoid having your Flight of Ideas derailed by French actresses dropping scented handkerchiefs.

Of course, you get more than 100uA to the surroundings through capacitance alone (just at LF), and you get capacitive dividers everywhere. Even without Hertzian waves (negligible for 25/50/60Hz), you lose voltage everywhere.

So logically, if you could step up the voltage sufficiently, you could lose voltage everywhere. :)

Tesla seemed to have a pretty good idea, except for the appreciation of resonant loss.

His works suggest that you can keep adding energy to a resonant system and it will stay there forever. In reality, a constant amount of power is required. This is why you can't shake a house to pieces with a fist-sized motor, it's too lossy.

Tim

The G-line

Take a minute. Divide it in half. Divide the remaining part in half. Continue forever, and the minute never ends, right? Same (mis) logic... So we have beat both power transmission and time!

What's a few sparks... I just hate it when my clothes stick to me, along with every bit of fuzz and lint in the room. And you should see the cat's reaction when I tried it--she freaked out.

Yea, but some day we'll figure it out!

What I want is unified connectors: power, signal and control in one (standard AC three pin) connector. TV: plug it in and it works. Phone? Plug it in and it works. Computer: Plug it in and it works!

Tesla had an excellent excuse, but the modern Tesla enthusiasts don't.

Cheers

Phil Hobbs

Why? Both were/are mad. ;-)

But they seem to take so much care in winding that tall secondary, they look quite pretty, that shiny enamelled wire cylinder. Quite useless, except for the Buzzt! factor long sparks ;)

I'm not talking about Tesla _coil_ enthusiasts. They're obviously doing worthwhile stuff--I mean, making 20-foot sparks is at least as useful as blowing up anthills with dynamite, for instance. Blowing up stuff is a logical consequence of having testosterone, it's fun, and it's occasionally a life saver.

It's the wireless power transmission / over unity / extracting continuous power from permanent magnets / loony types I'm fed up with.

Cheers

Phil Hobbs

My personal favourite was stuffing CO2 cartridges with wooden match head scrapings. Not ONE of the launch attempts actually performed like a rocket. They all blew up and grossly disfigured the angle iron launching ramps.

One 'trial' managed to uncurl a bit of decorative wrought iron railing that was holding the cylinder. On a Sunday morning, 8 AM.

The echo from the blast came back from a large building a block away. We cleared out of there NOW!

We were all lucky not to get killed or maimed by the shrapnel. There seemed to be a continent wide scourge of kids getting damaged by homemade rockets. The safe, commercially made model rockets were still years away.

It must have all been a billion to one odds series of events, as we all know that testosterone has NEVER, EVER caused stupidity in male adolescents.

mike

Female adolescents are morons too, just in a different way.

Cheers

Phil Hobbs

(Father of some of each)

Reminds of a problem a friend posed recently, if one gets a large strong rare earth magnet, and hangs a heavy weight from it to a steel beam in the shed, what's doing the work of the magnet holding up that weight? Wont the magnet 'wear' out?

Related, ever had an MRI? They put you in a big magnetic field, then they modulate that field to 'somehow' get images... Sound like a jackhammer, the operator side, they gave me headphones playing music to hide the noise (no metal in them, headphones had plastic tubes).

This thing was built big, solid, one could feel, hear the energy thumping around. Remove all metal objects from pockets quite some distance from the room with the magnet.

Grant.

Displays from large Tesla Coils often stimulate an interest in science and engineering in younger folks - not a bad end result...

Bert

Work is force times distance. Since the weight isn't moving, no power is required. If it does come loose, the weight as it falls will do work on the magnetic field, in such a way as to account for the extra field energy of the magnet in air vs. in contact with steel, plus a bit extra for the eddy currents.

Ever notice that nobody asks these questions about the electrostatic force, which is what holds solids together, including the beam, the weight, and the magnet? If the rope breaks, nobody wonders about the work done on the electrostatic field in the process, though it's mathematically similar and conceptually almost identical.

People have this idea that magnetism is somehow magical and mysterious, whereas it's been a matter for calculation and not speculation for over

Yup. NMR systems for research often have glass helium dewars inside there, so that a steel bolt flying into the magnet can make a _big_ mess.

Cheers

Phil Hobbs

Yep. The only time I've come close to claustrophobia :-( ...Jim Thompson

A friend reports the same, she needs to be sedated to go in there again. I was only in up to my knees :) I've been in the tunnel of a CAT scan machine, no jackhammers there...

Grant.

I thought I didn't need the earphones... never again will I make that mistake :-( ...Jim Thompson

Surprisingly, I didn't have any issues with claustrophobia and I generally get quite nervous in confined places. It was cold and the ventilation was quite good so perhaps my claustrophobia triggers weren't pulled. I didn't think the sound was all that bad, either. Weird, but not unbearable. If the operator weren't constantly trying to keep me calm I probably would have gone to sleep, since I got about zero sleep in the three nights I was there (two in a room, separate nurses with different schedules and a roomie watching TV all night).

Work is force * distance. If the weight is stationary, no work is being done.