AC:
I read the Tesla article. He certainly was very forward looking for sure and you can see how he was speculating about the arrival of the Information Age and most of what he said came true.
With respect to the ability to transmit power to light up a light bulb one mile away with very high efficiency, I am assuming that you are basing this on Tesla's writings. In other words, you are more or less basing your statements on the blind faith that Tesla was right. You are offering no mechanism for explaining this process.
Sorry, for myself I don't think like that most of the time.
Wow, I got lucky and found the clip, have a look at this: "1975 NASA JPL Goldstone Demo of Wireless Power Transmission"
http://www.youtube.com/watch?v=7O44WM1Q9H8That's the only way that I am aware of for doing high-efficiency point-to-point wireless power transmission.
The only way that you can transmit power point-to-point as per the Tesla example is with a line-of-sight system as shown in the clip. This requires that your transmitting wavelength is 1/10th or less than the diameter of your dish. As the wavelength gets longer you cannot direct the beam anymore and you end up broadcasting in all directions and your efficiency then drops to an abysmally low level. The technology to do this simply did not exist around 110 years ago. Since you claim that you are an engineer, that's what I was expecting you to say.
Going back to the last third of Tesla's article, I don't believe it. Simple as that. Tesla was either deluded or lying when he states that he could set up standing waves across the earth and that you could tap into that power with very high efficiency between the power source and the receiver. The surface of the earth is a lossy reflector and the ionosphere is also a lossy reflector, and all of this is a function of frequency. Your power is being spread across the entire surface of the earth such that your power density is extremely low. It's simply ridiculous to suggest that you can set up standing waves across the entire earth and tap into them with high efficiency.
For the light bulb experiment, my best guess is that Tesla had a huge steam engine driving a huge high-voltage dynamo connected to a huge high-voltage capacitor and some sort of motor driven discharge mechanism that operated at a certain base frequency. That resulted in the transmission of the fundamental frequency and all of the other unwanted harmonics associated with transmitting a square wave. All the energy associated with the harmonic waves would be lost by definition. He then created some sort of an antenna setup that was an LC tank circuit that was tuned to the fundamental frequency of the square wave and the light bulb was put across the nodes of the LC tank circuit. He found that if he pumped something like 50 kilowatts into the spark-gap transmitter that he could make a 100-watt light bulb light up one mile away.
So no, I don't believe that Tesla had a magic "secret sauce" for high-efficiency point-to-point electrical power transmission that we need to rediscover. The reality on the ground in the present day and age is that the most efficient way to transmit power over long distances is with high-tension power transmission lines. To go back to one of my earlier themes, the concept of the wireless transmission of high power was superseded by high-tension power transmission lines. Perhaps Tesla has the last laugh here because he probably designed the high-tension transmission line system in the first place when he built the world's first power plant at Niagara Falls.
For your MOSFET example, it's what can be expected, nothing remarkable there.
MileHigh
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Topic: Radiant Electricty, Cold Current, and all that... (Read 51407 times)
