Re: Coil Efficiency

From: 	Malcolm Watts[SMTP:MALCOLM-at-directorate.wnp.ac.nz]
Sent: 	Monday, July 28, 1997 3:51 PM
To: 	tesla-at-pupman-dot-com
Subject: 	Re: Coil Efficiency

Hi John,

> Seems to me that if one can quench the gap fast enough, this will 
> dim the gap also, even if the Q drop does not result in a critical k
> value?
> John Freau

Agree absolutely. I think that being able to do this = nirvana. In a 
sense, this is _also_ critical coupling because primary dissipation 
is minimized (minimal reflection back from the secondary). I wonder 
if this is what the Corums are referring to when they talk, albeit 
very hand-wavingly, about "critical" coupling?  Not having a gap 
system that can quench beyond what the coil dynamics allow means all 
the coils I've operated so far have been way overcoupled prior to 
spark production. The gaps in these systems quench when the energy 
has disappeared from the system.
     I would like to propose a two tests for quenching ability (and 
you _have_ to use a scope and HV probe):

(a) see whether you can quench a primary alone under single shot 
conditions (best of luck). Does your airblast noticeably affect the 
number of rings up to quench?

(b) set a system up to quench first notch under single shot conditions
and then progressively tighten coupling to the point where the quench 
no longer works to first notch. Compare this setting with that which 
you obtain with the air blower switched off. Is it the same for an 
attached spark as for an air streamer? What do the results say about
quenching affectiveness (yes, I think I already know the answers :)