NikolaTesla

The Greatest Hacker Of All Time?

The question comes up from time to time, who's the greatest hacker ever? Well, there's a lot of different opinions on this. Some say Steve Wozniak of Apple II fame. Maybe Andy Hertzfeld of the Mac operating system...Richard Stallman, say others, of MIT. Yet at such times when I mention who I think the greatest hacker is, everyone agrees (provided they know of him), and there's no further argument. So, let me introduce you to him, and his greatest hack. I'll warn you right up front that it's mind numbing. By the way, everything I'm going to tell you is true and verifiable down at your local library. Don't worry; we're not heading off into a Shirley MacLaine UFO-land story. Just some classy electrical engineering...

The Scene: Colorado Springs, CO.

Colorado Springs is in southern Colorado, about 70 miles south of Denver. These days it is known as the home of several optical disk research corporations and of NORAD, the missile defense command under Cheyenne Mountain. These events took place some time ago in Colorado Springs. A scientist had moved into town and set up a laboratory on Hill Street, on the southern outskirts. The lab had a two hundred foot copper antenna sticking up out of it, looking something like a HAM radio enthusiast's antenna. He moved in and started work. Strange electrical things began to happen near that lab.

People would walk near the lab, and sparks would jump up from the ground to their feet, through the soles of their shoes. One boy took a screwdriver, held it near a fire hydrant, and drew a four inch electrical spark from the hydrant. Sometimes the grass around his lab would glow with an eerie blue corona, St. Elmo's Fire. What they didn't know was this was small stuff. The man in the lab was merely tuning up his apparatus. He was getting ready to run it wide open in an experiment that ranks as among the greatest, and most spectacular, of all time. One side effect of his experiment was the setting of the record for man-made lightning: some 42 meters in length (130 feet).

The Man: Dr. Nikola Tesla

His name was Nikola Tesla. He was an immigrant from what is now Yugoslavia; there's a museum of his works in Belgrade. He's virtual unknown in the United States, despite his accomplishments. I'm not sure why. Some people feel it's a government plot, the same people who are into conspiracy theories. I feel it's more that Tesla, while a brilliant inventor, was also an awful businessman; he ended up dying penniless and broke. Businessmen who go broke fade out of the public eye; we see this in the computer industry all the time. Edison, who wasn't near the inventor Tesla was, but who was a better businessman, is well remembered, as is his General Electric. Still, let me list a few of Tesla's works just so you'll understand how bright he was. He invented the AC motor and transformer. (Think of every motor in your house.) He invented 3-phase electricity and popularized alternating current, the electrical distribution system used all over the world. He invented the Tesla Coil, which makes the high voltage that drives the picture tube in your computer's CRT, and in most cases, the spark that ignites the fuel in your automobile. He is now credited with inventing modern radio as well; the Supreme Court overturned Marconi's patent in 1943 in favor of Tesla.

Tesla, in short, invented much of the equipment that gets power to your home every day from miles away, and many that use that power inside your home. His inventions made George Westinghouse (Westinghouse Corp.) a wealthy man. Finally, the unit of magnetic flux in the metric system is the "tesla". Other units include the "faraday" and the "henry", so you'll understand his is an honor given to few. So we're not talking about an unknown here, but rather a solid electrical engineer. Tesla whipped through a number of inventions early in his life. He found himself increasingly interested in resonance, and in particular, electrical resonance. Tesla found out something fascinating.

If you set an electrical circuit to resonating, it does strange things indeed. Take for instance his Tesla Coil. This high frequency step-up transformer would kick out a few hundred thousand volts at radio frequencies. The voltage would come off the top of his coil as a "corona", or brush discharge. The little ones put out a six-inch spark; the big ones throw sparks many feet long. Yet Tesla could draw the sparks to his fingers without being hurt -- the high frequency of the electricity keeps it on the surface of the skin, and prevents the current from doing any harm. Tesla got to thinking about resonance on a large scale. He'd already pioneered the electrical distribution system we use today, and that's not small thinking; when you think of Tesla, think big. He thought, let's say I send an electrical charge into the ground. What happens to it? Well, the ground is an excellent conductor of electricity.

Let me spend a moment on this so you understand, because topsoil doesn't seem very conductive to most. The ground makes a wonderful sinkhole for electricity. This is why you "ground" power tools; the third (round) pin in every AC outlet in your house is wired straight to, literally, the ground. Typically, the handle of your power tool is hooked to ground this way, if something shorts out in the tool and the handle gets electrified, the current rushes to the ground instead of into you. The ground has long been used in this manner, as a conductor. Tesla generates a powerful pulse of electricity, and drains it into the ground. Because the ground is conductive, it doesn't stop. Rather, it spreads out like a radio wave, traveling at the speed of light, 186,000 miles per second. And it keeps going, because it's a powerful wave; it doesn't peter out after a few miles. It passes through the iron core of the earth with little trouble. After all, molten iron is very conductive. When the wave reaches the far side of the planet, it bounces back, like a wave in water bounces when it reaches an obstruction. Since it bounces, it makes a return trip; eventually, it returns to the point of origin. Now, this idea might seem wild.

But it isn't science fiction. We bounced radar beams off the moon in the 1950's, and we mapped Venus by radar in the 1970's. Those planets are millions of miles away. The earth is a mere 8000 miles in diameter; sending an electromagnetic wave through it is a piece of cake. We can sense earthquakes all the way across the planet by the vibrations they set up that travel all that distance. So, while at first thought it seems amazing, it's really pretty straight forward. But, as I said, it's a typical example of how Tesla thought. And then he had one of his typically-Tesla ideas. He thought, when the wave returns to me (about 1/30th of a second after he sends it in), it's going to be considerably weakened by the trip. Why not send in another charge at this point, to strengthen the wave? The two will combine, go out, and bounce again. And then he'll reinforce it again, and again. The wave will build up in power. It's like pushing a swing set. You give a series of small pushes each time the swing goes out. And you build up a lot of power with a series of small pushes; ever tried to stop a swing when it's going full tilt? He wanted to find out the upper limit of resonance. And he was in for quite a surprise.