No Subject

Plugging back into the Q equation.

Vs = 2.5 x 21000 == 52500 volts which is clearly wrong...

So use Vs = 1/2 x Vp x SQRT(Ls / Lp) and throw away Vs = Q x Vp unless it
is a CW coil.  IMHO  ;-)


Cheers,

	Terry


>
>If we could get about two dozen knowledgeable coilers to do these tests with
>their coils we could then pin down the TC secondary voltage and operating Q
>factor once and for all.
>
>John Couture
>
>-------------------------------
>
>
>-----Original Message-----
>From: Tesla list [mailto:tesla-at-pupman-dot-com]
>Sent: Sunday, August 27, 2000 11:55 PM
>To: tesla-at-pupman-dot-com
>Subject: Re: Q Factor and Overall Efficiency
>
>
>Original poster: Terry Fritz <twftesla-at-uswest-dot-net>
>
>Hi John,
>
>	Assuming an arc is 220K ohms plus 1 pF per foot of streamer.  One can make
>a little resistor and capaictor to simulate this streamer load.  Simply
>connecting a secondary to ground through this load allows one to measure a
>secondary systems Q as it is with a load with a signal generator and scope
>looking for the center frequency divided by bandwidth method.  Nothing too
>dramatic will be found but sort of fun to do...
>
>Cheers,
>
>	Terry
>
>
>At 05:46 PM 8/27/00 -0700, you wrote:
>>
>>The Q factor tests have been discussed many times in past List posts.
>>However, these tests give the Q factor in a low voltage condition. This is
>>not the TC operating Q factor. The operating Q factor would give the
>>secondary voltage with the equation
>>    Vs = Vp * Q
>>where Vp is the primary peak voltage.
>>
>>To find the operating Q factor would require only a scope and the proper
>>probe and the knowhow. To do the test find the half power points while the
>>Tesla coil is operating. Then determine the Q factor with the equation
>>    Q = Fr/(Fh - Fl)
>>where Fr is the resonant frequency, Fh is the higher half power frequency,
>>and Fl is the lower half power frequency. The Q factor would be the voltage
>>gain from the TC input to the TC output. This gain could then be used to
>>find the overall efficiency of the TC system. This would be done using the
>>energy equation
>>     Vs = sqrt(2J/Cs)
>>Overall efficiency would be the Vs(half power) test volts divided by the
>>Vs(energy) theory volts.
>>
>>This operating Q factor and TC overall efficiency may be a first in the
>>design and engineering of Tesla coils. However, Terry Fritz may have
>already
>>done this? Have other coilers done this?
>>
>>John Couture
>>
>