12/08/2022
"Work on high frequency alternators was begun by me in 1888, in my laboratory at 89 Liberty Street. I had just completed my system of power transmission, which is now universally adopted, but several problems yet remained to be solved. One was to run my induction motors at very high speeds; another one was to adapt them to the then existing alternating circuits of supply of 133 cycles. These two problems, although they were diametrically opposite, both required the use of laminated structures with a great many poles or polar projections, and I constructed quite a number of these with the object of improving along the lines indicated. Among these was an alternator with 24 poles, which gave me 12 cycles per revolution. This I used originally in running some small induction motors at speeds up to 200 revolutions per second. Occasionally, however, I would use this alternator in other experiments, with transformers, etc., and condensers, and then by running it at high speed (10,000 RPM) developing something like 2,000 cycles per second, which phenomena were entirely new. This, of course, interested me very much, but the work was interrupted in 1888 when I had to
go to Pittsburgh to attend to the manufacture of the motors. On my return to New York the next year, that was early in 1889, I engaged a laboratory at 175 Grand Street, close to Center Street, and there is where I undertook to design and construct the first high frequency machines. I had at that time already perceived enough to get the idea that energy could be transmitted without wires. It was of no consequence to me at that time whether it was to be used for telegraphy, or telephony, or power transmission. I was on the problem of transmitting energy without wires; and as it is my custom always to analyze scientifically every problem that I undertake to solve, I devoted a great deal of thought to how to attack that problem, and the following crystallized out."
–Nikola Tesla
(In a pre-hearing interview with his legal counsel in 1916 to protect his radio patents from Guglielmo Marconi)
(“Nikola Tesla On His Works With Alternating Currents and Their Application to Wireless Telegraphy, and Transmission of Power.” Twenty First Century Books, Breckenridge, Colorado, 2002.)