Original poster: Ed Phillips <evp@xxxxxxxxxxx> Tesla list wrote:
Original poster: "Langer Giv'r" <transworldsnowboarding19@xxxxxxxxxxx>Hello, I am wondering about the frequency of output of my Tesla Coil. I know that the EM wave radiates with a fundamental frequency of whatever your coil resonates at, but does it also exhibit harmonics as well? for example, my coil resonates at 260kHz, so then would it be correct to say it radiates EM waves at 260kHz, then at conciderably less energy 520kHz, 1040 kHz, 2080 kHz, and continuing until all energy is absorbed?Thanks for the help
You are certainly correct that there is SOME radiation but it will be very small because the coil is a most inefficient radiator because of its length compared to the wavelength of the signal in it. The coupling from the primary circuit will be much higher at the fundamental frequency than at any harmonics so there won't be much harmonic current flowing in the secondary. On the other hand, the radiation efficiency of a very short antenna increases as the square of the frequency so any harmonics present will be radiated more efficiently than will be the fundamental. Seems to me I read something here (or in the TCBA Journal) about some experimental data on the subject and I've always wanted to drag home a spectrum analyzer and try to make some measurements. If anyone has done anything recently Terry must be aware of it.
Ed