Re: A few Q's from a beginner

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>" <FutureT-at-aol-dot-com>

In a message dated 3/30/02 2:29:00 PM Eastern Standard Time, tesla-at-pupman-dot-com
writes:

Robert,

I am not as confident as you are that the best form is a 45 degree
form.  I also don't see anything difficult about building it.  I also
would not say that a flat primary has less efficiency.  I also would
not say that a solenoid coil has the best coupling or power transfer.
I also would not say that solenoid coils have more racing sparks,
and arc over problems.  Any of the primary shapes can be easily
adjusted to give optimal coupling, and power transfer, without 
arc-over or racing sparks.   

It's true that a solenoid coil can give the tightest coupling, 
but tightest does not necessarily mean optimal. 

I've used a flat primary for a tube coil, and that worked fine too,
and was quite efficient.

Certain shapes may have less inductance for a given wire length,
thereby increasing the losses, but the results on spark length 
will probably not be noticeable.

Cheers,
John


>
> Brad: the costruction of the primary is a trade-off. The best form is a 45o
> cone slightly above the base of the secondary. This is hard to construct and
> mount. A flat primary has the least coupeling problems and is easy to
> construct, but has the least efficency. A solinoid primary has the best
> coupeling and power transfer, but the most arc over and running arc
> problems. It is the easiest to construct and most trouble. Tube TC coils use
> the solinoid coil primary because they nead the best coupeling to oscilate.
>