Interesting Historic Footnote:
On page 26 of Worley's "Iron Horses of the Santa Fe Trail," there is a photo of a small steeple-cab, panatagraph-less, electric locomotive lettered "Wireless Power Transmission Corperation, Providence, Rhode Island. The caption states that the photo was taken somewhere in Colorado in 1935 as the loco was on its way to a test sight in the Rockies. I know that around the turn of the century, A.C. power genious Nikoli Tesla was doing wireless power transmission experiments near Colorado Springs(which blew out the local generator). His big dream was to send electrical power without wires, and many say he, in fact, did it.

I was just wondering if any body new of any connection to Tesla, and what if anything came of the experiment.

lorija799@aol.com

Nothing ever came of Tesla's experiments probably because, as a practical matter, there was no advantage to his methods.

Unless he was playing with some aspect of electro-magnetism that no one but him knew of and which has not been rediscovered since (unlikely), Tesla was probably monkeying around with power- or audio-frequency (10-10,000 Hertz) fields.

Efficient radiation of such fields is no mean trick-- the antenna structures get ridiculously large at such low frequencies.

Even if one can efficiently "launch" such fields into space (that is, without most of the energy content of those fields being consumed in heating the antenna elements, transmission lines, and the very earth under them), one has a corresponding problem on the receiving end-- the receiving antenna has to be every bit as large and unwieldy as the transmitting antenna if any amount of useful power is to be "picked up". And that's assuming that there's any power to be picked up, being as how the transmitting antenna is most likely sending its power out in all directions, not just directly at any particular point.

Some of that old-time electrical appartus operated at unexpectedly high frequencies-- it's been pointed out that microwave technology is really rather old: Heinrich Hertz was playing around with 10 Ghz (3-centimeter) waves as early as 1885 or so.

It may be that Tesla was working with similar stuff, and it is possible to transmit useful amounts of electrical power via microwaves. But for obvious safety reasons, the intensity has to be kept low, so low that (again) the size of the antenna needed to gather a useful amount of power (to power, say, a locomotive) becomes very large.

Between the technical difficulties of transmission and reception, and the need to meter the use of power (so as to know what to charge whom how much), it was just easier all said and done to go with a wired system.

No conspiracies needed to explain this one. ;)

Hale Adams

ahadams1@ix.netcom.com

I also read that although he could light tungsten ligbulbs at about 200', greater distances weren't practical.

> I also read that although he could light
> tungsten ligbulbs at about 200', greater
> distances weren't practical.

Fluorescent light-tubes are a snap to light up without using wires. Just place one in a strong-enough radio-frequency electro-magnetic field and it'll light right up.

I remember one night when some friends and I (we are all ham-radio operators) weren't having much luck making 2-meter (144 MHz) contacts from a local hilltop. Just to kill some time we lashed a 40-watt fluorescent tube to the end of a 12-foot stick and raised the tube up into the air in front of the "business end" of a ten-element Yagi antenna fed with a 170-watt amplifier (or "brick").

One of the guys keyed the transmitter and the tube glowed quite brightly, staying lit (though getting dimmer) until the tube was about 20 or 30 feet away from the antenna.

The RF field at the end of the antenna was strong enough to agitate and ionize the mercury vapor in the tube, which in turn caused the phosphor lining in the tube to glow, just like in normal operation.

A tungsten-filament lightbulb would require more apparatus-- something like a coil of wire to act as a "pick-up" or antenna, which could then be hooked up to the lightbulb.

In any case, the distance is quite limited because of the inverse-square law. Double the distance from the source, the effects decrease to one quarter their former size. Triple the distance, and the effects shrink to one-ninth their former amount, and so on.

That's why "wireless power" never caught on.

Hale Adams

ahadams1@ix.netcom.com

For information on what is being done today in research on Tesla energy transmission. Go to any good search engine and do a search on Project HAARP. This is a U.S. Dept. of Defence research facility in Alaska operating under the guise of the University of alaska, Fairbanks. It is operational. Mark D.

mnmach@lakes.com