More Mini Coils

From: 	Malcolm Watts[SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent: 	Thursday, June 19, 1997 2:45 PM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: More Mini Coils

Hello John, all,

> From:   John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
> Sent:   Wednesday, June 18, 1997 9:53 PM
> To:     Tesla List
> Subject:    Re: More Mini Coils
> At 07:48 AM 6/18/97 +0000, you wrote:
> >
> >
> >----------
> >From:  Greg Leyh[SMTP:lod-at-pacbell-dot-net]
> >Sent:  Tuesday, June 17, 1997 11:55 PM
> >To:    Tesla List
> >Subject:   Re: More Mini Coils
> >
> >Robert W. Stephens wrote:
> >
> >> 
> >> Not to rain on your parade or anything but I just have to correct
> >> you.  What Malcolm achieved was most definitely *NOT* 60 watts per ft
> >> of discharge.  He reported producing some 4 inches of discharge for
> >> 20 watts input.  
> >
> >20W / 4in = 60W/ft by my calculation.  Remember, the unit W/ft is not
> >a length, but is rather a ratio used to determine coil effectiveness.
> >
> >> As we (that have actually gotten our hands dirty and
> >> built coils that is, and I'm not saying you haven't) know well, the
> >> ratio between input power and output spark length is far from linear.
> >> Streamers issuing from a topload terminal seem to crave increasing
> >> power at an exponential rate to their length.
> >
> >All too true :^<   Perhaps a more direct measure of coil effectiveness 
> >would be to normalize the W/ft ratio to operating power level. 
> >None the less, Malcolm's 'little wonder coil' does provide an 
> >interesting data point, in a sparsely populated area of tesla coil
> >parameter space.  Way to go, Malcolm!
> >
> >-GL
> >
> -------------------------------------------------
>   All -
>   Was that a controlled spark length? Watts per spark length for the same
> coil can vary greatly depending on who does the measuring. Maybe someday
> coilers will agree on how this important TC parameter should be determined.

Dear me. I obviously haven't been entirely clear on this. You know 
what a high-powered attached discharge looks like, right? Well that 
is exactly what I have consistently got with the system in question.
There is no leeway for error. I am talking point-point! If you don't 
believe me, reproduce the experiment. You have all the data necessary. 
I am not into giving all my hard work away, but on this occasion, I am
observing the rules applying to verification because I didn't 
photograph the result. I doubt whether anybody is going to measure 4"+
any differently from myself.

>   Keep in mind that the secondary terminal can be charged by more than one
> break/charge before it will discharge. In that case the wattage per spark
> length is doubled or tripled etc. per spark!

Personally I say that is completely wrong. I would like to see a 
substantive proof of that statement. I scoped this system running. The
secondary duty cycle was no more than 5%. It was completely quiet for 
the bulk of the time between gap fires. This is no different to any 
other system I've scoped either. 

>   Note, also, that the primary capacitor can never be charged to more than
> the source voltage by increasing the input wattage. Why does increasing the
> input wattage hopefully increase the secondary voltage if turns are not
> involved?   Vs = Ls di/dt  is not resonance.

You increase the BPS if your quench allows it. This is exactly what I 
achieved by closing the gap up. Power input was constant. It was the 
extra ionization at a lower output voltage which allowed the 
streamers to coalesce into a single channel.

>   How should the input wattage and the power factor be measured for the
> surges of input current?
>   After many years of research I am still pondering these TC questions. 

Best of luck.