Re: Base current......Re: Tesla Coil RF Transmitter> please advise

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: d a <btoc3000@xxxxxxxxxxxx>

eh..

in layman terms, is this the explaination....

The high RF current at the base sinks into the RF ground and travels 
to the topload terminal via the air through displacement. So, if we 
place a light bulb in between the RF ground and the terminal - this 
displacement current will travel from the RF ground to the topload 
via this bulb, thereby lighting it up in the process. This light bulb 
can also be perceived as a "receiver", akin to a radio receiver. 
However, this system is not effective because if this light bulb is 
placed far away from the tesla coil, it will not receive sufficient 
RF to light up the bulb.

The RF ground is 'purposely' there to remove the high RF current such 
that this high current from the base will not be able to travel to 
the topload. Otherwise, the topload will not be able to have the 
minimum current possible and the voltage will not be at its maximum then.

Another reason for the RF ground is such that the tesla coil will be 
able to act as a RF transmitter. I mean, having a RF ground sinking 
the high RF current, so there must be another equivalent high RF 
current "entering" the topload. However, if that is the case why do 
we say that the current at the topload is at its min, ideally 0?

Please advise.
Thanks, Sam


Tesla list <tesla@xxxxxxxxxx> wrote:
Original poster: dave pierson



> If current flows into the ground an equal amoung MUST flow through
>whatever you call the thing on top of the coil.

While largely in agreement with the rest, this i pause to ponder over.

> There is no way his configuration could have behaved other than
> as a transmitter with a
>short top-loaded antenna.

Consider classic 1/4 wave antenna over ground.
Voltage peak (minimal current) at top.
CURRENT PEAK AT BASE !

Need the current be the same at both ends?
DC Case, yes.
resonant AC case????

(For the Tesla Coil Case I'm 'implying' no break out...
In case of breakout, all changes....)

I suspect this 'current peak at base' accounts for the need,
especeially with high power coils, for a really good rf ground.....

(I am not invokin g 'new physics', rather conventional
antenna concepts....)

best
dwp



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