TV's, Antennas and strange things

Well, your assumption turned out to be correct. Welcome to the world of magnetic induction. An antenna is a device that captures EM waves, and in turn induces an AC electrical current. And as you've already suggested, an (AC) electric current will induce a magnetic field. Have you ever heard of building a radio receiver that doesn't use batteries or a power source of any kind? The same principles apply. EM waves and AC current act in the same manner, and this makes it easy to convert information between the two. The alternating current induced from the EM wave is sent to a speaker. The speakers diaphram oscilates with a direct relation to the alternating currents frequency that is applied to it. The frequency that the diaphram oscilates at is converted to pressure waves that we hear as sound. The beauty of all of this, is that the reverse is true. You may have heard before that you can use a speaker as a microphone, and in truth they're essentially the same thing. A speaker is a magnetic induction motor. You apply an AC current to the speaker, and the magnetic induction causes the speaker to oscillate based on the AC frequency. Just like the antenna though, you can induce an AC current into a speakers terminals by causing the diaphram to vibrate. This is essentially what a microphone does. The diaphram of a microphone is tuned to be most responsive to the frequencies that the human voice produces. The vibrations from the human voice induce a current which is sent to a preamp stage to be amplified even more. Finally before I get too off topic, an electric motor and an alternator that recharges the battery in your car are again, the same thing. Current fed to an electric motor will induce a magnetic field which drives the motor. Take that same motor, and put a crank on the end of it, and start winding. The magnetic induction that you create will induce a current at the motors terminals. Ok, that was very long winded. Maybe a bit too much. What it comes down to though, is that magnetic induction is a two way street. I hope you've learned something today. :)

Full props to useradd I never knew any of that either and it probably would have confused the hell out of me to hear the sparking sound and see that magnetic effect too. Just how did you learn something like that??? Definetely one of the best responses I have ever read on mylot and you get my "+" rating for such a marvelous insight into the world of magnetic forces and electricity.... (not hard I guess coz I am useless when it comes to science being a musician and all).