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Re: Secondary Theory (Was Bipolar Coil)-Heretical view

Hi Ed,

	To measure the primary circuit resistance, I hook the fiber optic scope
probe up to the tank cap and fire the primary circuit without the secondary
coil and terminal in place.  The tank circuit will ring down and I can
measure the time this takes.  I can then find the equivalent resistance
that will produce the same ringdown time in the RLC network. 

	The secondary is done in a similar way but I usually go to a very good
quenching gap so that the secondary can ringdown without the primary
influencing it.  The ringdown time is measured under low power no breakout
conditions and I use the plane wave field antenna to record the waveform.
The ringdown time is again used to estimate the secondary circuit's
resistance. 

	Last year's post about my measurements and Greg Leyh's electrum
measurements, determined that his giant coil and my test coil were both
driving the same arc impedance which was equivalent to ~220000 ohms in
series with a 5pF cap.  This was remarkable in that our two systems have
vastly different power levels but seemed to be seeing the same load
impedance.  The equivalent cap and resistor load has been used in many
models that accurately simulate the load on the system. Interestingly, it
seems to be fairly linear and time-invariant.

	It is interesting that as the variac power is turned up, the impedance of
the arc (as noted by the waveform shape) does not change much.  This
indicates that the impedance of the arc is relatively constant per power
level too.  However, with so much power being burned in the gap, maybe I am
seeing the gap limiting the system much more that the streamer load. 

	This is still a little unclear to me and I am working on a better system
to study this more.  More test are needed to pin all this down better...

Terry




At 06:09 PM 5/17/99 -0700, you wrote:
>Terry et al:
>
>	How do you model the non-linear and non-time-invariant resistance of
>the streamers from the secondary?  There's been a lot of talk here about
>"critical coupling", but factor doesn't mean anything without specifying
>both the primary and secondary circuit Q's.
>
>Ed
>
References: