Re: [TCML] Is this right?

[resonance@xxxxxxxxxxxx]

Brooke Clarke is certainly confused.  To assert that all coils operating
at resonance have a Q of only 1 is not correct.

Bart's excellent JAVATC program sets parameters that set the pri and sec
coils at resonance, and then calculates the Q factor of the resonant coil,
usually in the 200-300 range for most coils.

Experimenters can also use the 10% decay procedure using an oscilloscope
to actually measure the dynamic operating Q of any Tesla coil.  It's
usually in the range of 10 to 50.  Certainly higher than 1.

Rich Hull has also dispelled the myth about resistance being important. 
His short 34 inch long sec coil wound with #30 AWG wire was spewing forth
an 11 ft long spark and $30 AWG is certainly not the lowest possible
resistance.


99% of coilers are correct --- operating Q is almost always greater than
1.0.  Clarke is wrong --- probably never built a Tesla coil and measured
anything.

Dr. Resonance




> Hi Ben,
>
> I really don't understand how Brooke Clark could have ever come to the
> conclusion that a self-resonant coil has a Q of 1. This is easily
> refuted by a few simple measurements, and most well constructed Tesla
> Coil resonators easily achieve Q's in the range of 200 - 300. It sounds
> like Mr. Clark is simply a bit confused about Tesla Coil operation and
> practical Q measurements for unloaded and loaded Tesla Coil resonators.
> Q is a measure of the energy stored in the inductor divided by the
> energy lost PER CYCLE. One form of Q can be written as:
>
> Q = 2*pi*Fr*L/Rac
>
> where
>   Fr = resonant frequency
>   L = Inductance
>   Rac = equivalent resistance of inductor at Fr
>
> It can easily be seen from the above equation (and easily experimentally
> confirmed) that Q actually $decreases when external capacitance is
> added, since this lowers the resonant frequency of the circuit. There
> are a significant number of other inaccuracies on Mr. Clark's site as
> well...
>
> The TCML used to modify all URL's and email addresses by substituting a
> "dot" for a "." in an attempt to thwart 'bots from harvesting addresses
> for spammers. Don't know how well this worked though.
>
> Bert
>
> Ben Sneath wrote:
>> hello all,
>> i found the on the website:  www.prc68.com/I/electron.shtml
>> (if the link shows up)
>>
>> ...All of the above is very important since a coil operating
>> at it's self resonant frequency has a Q of 1, no matter how
>> it was made.  (This is something that 99.99% of the Tesla
>> coil builders don't get.)  So in order to get high Q you
>> need to load the coil with a capacitance that's
>> substantially larger than the self capacitance.   You can
>> see the it's very important to not only wind the coil in
>> such a way that the HF resistance is minimized but also in
>> such a way that the self resonant frequency is as high as
>> possible...
>>
>>
>> is this true? secondry with a Q of 1 no matter what when @
>> its res. frequency?????
>> if it is right then how does that happen??
>>
>> BTW...why in older posts was the "." replaced with the word
>> "-dot-" in links?
>> _______________________________________________
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>


Dr. Resonance

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