Re: TC Primary Q Voltage Magnification

[Terry Fritz <twftesla-at-xxxxxxxxxx>]

Hi Ted,

At 08:13 AM 11/20/2000 +1300, you wrote:
>Team
>
>Would I be correct in thinking that when the SG fires the equivalent circuit
>of the primary is a series resonant cct. 

Yes.

>If so, the potential for Q voltage
>magnification would need to be considered particularly in relation to the
>voltage across the cap.

Nope!  For the voltage to continually increase to the initial voltage
multiplied by the Q, you would need to keep adding addition energy to the
circuit.  In our case, when the gap fires, all the circuit's energy is
stored in the primary cap as 1/2CV^2 Joules.  We have no place to get
additional energy to raise that voltage higher.  If the circuit were driven
by a low impedance sine wave source at the Fo frequency, then the voltage
across the cap would increase to Vi x Q if it would not blow to bits first ;-))

>
>The loaded Q is probably low but even then the effect on the total voltage
>present is significant ??

I calculated to loaded Q of one of my coils at 2.5.  But without more
energy to pump into the circuit, Q does not seem to matter much.  Below is
a graph of my big coil's Q and a paper that shows the associated waveforms.

http://hot-streamer-dot-com/TeslaCoils/Misc/BigLtr-VvF.gif

http://hot-streamer-dot-com/TeslaCoils/MyPapers/modact/modact.html


Cheers,

	Terry

>
>Tnx
>Ted
>