Re: 7.1Hz, how the heck did Tesla succeed?

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>

Hi,

At 08:45 AM 7/17/2005, you wrote:
> Tesla list wrote:
> > Original poster: Steve Conner <steve@xxxxxxxxxxxx>
>
> > He didn't realise that displacement current cancelled out practically all 
> > the radiated power in the far field. The currents that Tesla thought he 
> > was "pumping into the ground" were getting sucked right back out again. 
> > This is understandable since Maxwell had only just "invented"
> > displacement current.
>
> Steve,
>
> What is the location and in what element do these displacement currents occur?

They occur between the top terminal and closely surrounding 
ground.  Basically as the top terminal capacitance to ground.  The 
displacement currents basically act as a low impedance return path that 
supports the oscillation of the coil.

If a coil runs at 100kHz and the coil is 5 feet high, it would be 
interesting to see how good of a radiator it would be as a pure short 
antenna.  That might help us estimate how far the electrical noise goes at Fo.

Of course, the "real noise" is far higher up at say 25MHz from the gap 
wiring and all, so the "antennas" are much better radiators then.

>    Where do they originate and in what direction do they travel?

Top terminal and ground in a bowed pattern between.

> Are they time variant or are they DC and follow Kirchhoff's law as some 
> suggest?

Time variant, but little antenna length phase effect since the coil is so 
short.  If the coil was a straight wire 2459 feet long (C / 4Fo), then it 
would radiate well as a 1/4 wave antenna with nice far field phase 
effects.  But that would just be a plain "old" spark gap style radio...

Cheers,

        Terry


> stork