Re: How to rise the secondary? (fwd)

---------- Forwarded message ----------
Date: Mon, 27 Jul 1998 06:31:51 +0000
From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: How to rise the secondary? (fwd)

  Antonio -

  Do you believe that a raised secondary TC can produce longer sparks
compared to a properly designed TC where the secondary does not have to be

  Please - yes or no.

  John Couture


At 10:34 PM 7/25/98 -0600, you wrote:
>---------- Forwarded message ----------
>Date: Sat, 25 Jul 1998 12:16:55 -0700
>From: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br>
>To: Tesla List <tesla-at-pupman-dot-com>
>Subject: Re: How to rise the secondary? (fwd)
>John H. Couture wrote:
>>   Theoretically you could go a 10 ft beyond the arc-over point and it would
>> only take more time to transfer the energy and would produce the same spark
>> length. However, if the tuning is inseparable from the coupling then there
>> would be a reduction in spark length because tuning affects the amount of
>> energy transferred.
>The tuning affects the coupling, as it affects the geometry of the system and
>the primary inductance, but just moving the secondary does not affect the
>inductances. If it changes the tuning the reason must be due to changes in
>parasitic capacitances. The main reason why the energy transfer decreases to
>far below the ideal theoretical value if the secondary is moved too far away
>from the primary is because the primary field couples to other "receptors"
>nearby, and little energy effectively reaches the secondary.
>>   There have been hundreds of articles in the past that have tried to
>> explain how a Tesla coils works. All of these articles ignore many details
>> that indicates we still have a lot to learn about Tesla coil operation and
>> design. When it comes to magnifiers we are only in a primitive testing stage
>> so empirical design is not possible. It could turn out that when we learn
>> how to design the optimun classical Tesla coil the magnifier will not be
>> required.
>I don't think so. A Tesla coil, or a magnifier, is a very simple device,
>and there are no problems at all in modeling how it works with the known
>With very little theory it is perfectly possible to build one that works,
>as effectively there is no optimum design, or the optimum is very broad, and
>in most cases it is possible to reach the optimum by just tuning one or two 
>points (primary tuning and coupling).
>The theoretical problem is how to obtain accurately the correct parameters to 
>model the several distributed affects in these devices. And consider also that 
>the main objective is to produce sparks, that are a very randomic phenomenom,
>subject to subtle influences from many factors.
>Antonio Carlos M. de Queiroz