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Re: 50%

Jack,
         I'd like to comment on some of the points made in your post 
to Bert

> 1. The commonly accepted  limit of 50% transfer (efficiencies?) is for the
> current and power and not for the energy transfer limitation. This is a
> common mistake made by many people.

Would you be able to make a clear distinction between the two please? 

> 2. Energy cannot be transferred instantaneously so the amount of transfer
> time is important and is determined by the coupling. The coupling must be
> correct for the 100% transfer of energy.
 
Agree.

> 3. The coupling does not take part in the energy transfer itself but is
> important in determining the transfer time. Maximizing K should be to
> coordinate the transfer time so 100% of the energy is transfered. 

I have a problem with that. Maximizing k (i.e. k approaching 1) 
certainly allows energy to get across in the quickest possible time. 
But various values of k (0.6, 0.385, etc the magic numbers) _also_
ensure that transfer runs to completion. 

> 4. Critical coupling may not give the correct time for 100% energy transfer.

Our coils are overcoupled, period. They all give a double-humped 
unloaded response. When two circuits are critically coupled, it is 
axiomatic that an equal amount of power is dissipated in the source 
and load impedances. 

> 5. Quenching the gap at the appropiate time is important so all of the
> available energy is transfered. Proper quenching is also important for other
> reasons not related to enrgy transfer.

Agree
 
> 6. To obtain more output (spark length) with maggies compared to classical
> coils would not require more efficient energy transfer for the primary to
> secondary coils because it is already at 100%. However, it would require
> less total loss in the system which appears to be possible. 

Well consider that magnifiers are typically run with a higher k in 
the pri-sec system than the typical 2-coil jobs. The magic there is 
fewer gap conductions (=losses) in effecting a complete transfer.

> I have never seen calculations of controlled tests that maggies do
> produce longer sparls compared to a properly designed and adjusted
> classical coil.

I think it is possible at higher k's for the reason stated above.

Comments?
Malcolm