Re: Wire Length

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Ed Phillips <evp@xxxxxxxxxxx>

Original poster: "Gary Peterson" <g.peterson@xxxxxxxxxxxx>


> > We know that Tesla was using the flat spiral 
> > coil as a spread-spectrum wireless transmitter.
>
> We do?


Ed,

Are you questioning whether Tesla was using the 
oscillator as a wireless transmitter, or whether 
it was part of a secure wireless system that 
depended upon the conjoint action of two 
differently tuned RF circuits, both located at 
the receiving end, and functioning as an AND logic gate?"

    Not at all, but this doesn't meet any 
definition of "spread spectrum" which I've ever 
seen and the term has been in use in 
communications and radar circles for a long 
time.  Straightforward enough and there have been 
many such systems used over the years.
Question referred to spread spectrum.

> . . . Tesla . . . is apparently referring to the two

> different frequencies which can be produced 
> while the primary is being excited.


Tesla is referring to the two different 
frequencies that can be produced, one when the 
primary is being excited and the other when the primary circuit is open.

"This coil I excited by a primary so proportioned
that when the primary was closed by the make-
and-break disk which discharged the condensers,
the oscillations in the secondary were quickened
much above the rate which the secondary or spiral
vibrated when the primary was opened."

   I think this amounts to the same thing but 
not so sure as the language seems a bit obscure. 
Certainly possible with appropriate tuning which 
I think is what he's saying.  He was writing a 
lot of this at a time when there wasn't really 
any standard terminology [generally accepted 
engineer slang].  Of course, if the coupling is 
high enough, there can be three frequencies 
produced, two while the discharger/spark is 
conduction and, depending on the tuning, a third 
when the primary circuit opens and the secondary 
"rings free".  I haven't anything he wrote which 
make it clear he understood that or not.

"Responding to this post gives me a sense of déjà vu.

Gary Peterson"

Ed