I read a story that Royal Raymond Rife had originally broadcast his frequencies by means of an RF (radio-frequency) antenna. He apparently did his testing "late at night/early morning" because it would cause radio interference in the surrounding neighborhood.
Rife would send an assistant outside with radio and drive around to check the distance of the interference. Now, these were the early days of the radio so the radio commissions in place had not place heavy restrictions in place.
That being said Rife then switched to the plasma tube/bulb and found that it did not create any appreciable radio interference. I also have a plasma system from another supplier based on a radio frequency generator/amp & antenna tuner hooked up to a plasma tube. If I put a child's walkie-talkie (2 way radio) close by it will pick up the whine of the frequency transmitted from the plasma tube (believe it or not it will penetrate thru basement concrete walls for a short distance.
Jim Bare had mentioned that you are not allowed to hook up an antenna in place of the plasma tube because the radio interference would be noticeable by the authorities (and probably a "knock at your door" would follow..). From what I've read the plasma puts out longitudinal waves and not radio per sec. So we apparently have very little to worry about as long as we stay within the proper use of the plasma tube.
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