RC Ken mentioned that Hedy Lamarr invented Frequency hopping. This is actually an interesting story if anyone wants to research. Hedy was married a number of times and one was to a weapons producer. Something in this field rubbed off on her from him. In Hollywood, she met a guy named George Antheil who she shared the patent with. Antheil was a musician, but the story goes that she actually approached him over breast enlargement. The subject eventually turned to weapon developement and they came up with an idea for torpedo guidance by frequency hopping. This was to be achieved with piano rolls. There were 88 frequencies to be used....the same number as keys on a piano. A patent was granted, although no one thought it would work. The Navy blew them off. In the 50's, someone at Sylvania rediscovered the patent and was eventually used for secure satellite communication. This was also put to use for ship to ship communication during the Cuban missile crisis. The patent has long expired and is in many technologies we use today, including R/C. Hope I got all this right....I am surprised there is no movie on this...or maybe there was....

bob