Re: Conditions for opt. loading, was: In vs. Out

From: 	FutureT-at-aol-dot-com[SMTP:FutureT-at-aol-dot-com]
Sent: 	Friday, August 01, 1997 4:39 AM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: Conditions for opt. loading, was: In vs. Out

> I'll give it a shot...
> We all know there's a very non-linear relationship between coil power
> level and streamer length. John has suggested that, based upon empirical
> evidence, there seems to be a square-law relationship for Tesla Coils.
> It becomes increasingly more difficult (i.e., takes much more power) to
>significantly extend sparklength if we already _have_ significant
> sparklength. This implies that if we halve the total power going into
> one of the twin coils, we won't halve the streamer length coming from
>that particular coil. Doubling the input power will increase streamer
> length by a smaller factor - say by 1/4 or 1/3 depending on our current
> power level. 
> For example, a single coil operating at full power might provide 6 foot
 >streamers. The same coil operated at half that power might output 4
> footers. A twin system, operating at the former full power level equally
> shared between the two coils, might thus be expected to deliver 8 foot
> connected streamers - an apparent 33% improvement over a single coil for
> the same tank circuit power.  As we increase overall power levels, we
> would expect to see greater apparent benefits in increased streamer
> length versus a single coil. Twins appear to run "hotter" if we use 
> sparklength/watt as a metric, and the apparent benefits over a single
> coil improve as we increase power levels.
 >Safe coilin' to you!
 >-- Bert --

Bert, Malcolm, All,

I agree with your fine analysis, and this had occured to me also.  In
fact, I always "de-rate" twin coil spark lengths by an appropriate factor.  
Twin coils give a misleading impression of spark length improvement.
All else being equal, a twin will always "beat" a single coil in connected
spark length.

My comments about possible benefits of twin coils refered only to
ease of quenching due to possible more optimal loading, not to any
spark length gain.  (Just wanted to clarify my viewpoint, just in case
it wasn't clear enough...but it probably was.  :)

Coiling towards the Millennium, HO!

John Freau