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

Original poster: Jim Lux <jimlux@xxxxxxxxxxxxx>

At 03:08 PM 7/18/2005, you wrote: 
Original poster: Ed Phillips <evp@xxxxxxxxxxx>

"Sure, but Q is energy lost vs energy stored in one cycle. In a time
varying system what's the period of one cycle? Q is a nice shorthand
to compare various resonant systems, but except for trivial systems
it doesn't work all that well. Probably a better way to look at it is
in terms of phase noise."

        The definition of Q I was taught was really ratio of energy stored to
dissipated per cycle, not in one.


You're right.. what I meant was in a single cycle (i.e. per cycle).. ratio of energy stored/energy lost.


 Q has always been a useful parameter
for me.  It's a measure of (reciprocal) loss and not of noise per se.

I was thinking of the "bandwidth" interpretation of Q (i.e. center frequency/3 dB BW) which really isn't relevant except for a single tuned circuit. The earth, as resonator, is hardly a single tuned resonator.


Ed