Re: tapped primary

["Finn Hammer" <f-hammer-at-post5.tele.dk> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Jeremiah!

When you start to design your coil, there are unknown factors that need
to be accounted for. So you build some slack into it.
Relating to your specific question, this means that you build the
primary coil with more turns than you really need, and then "tap" it at
a point further in on the coil, than at it`s outher end. The connection
to the coil that can be moved is then called the tapping point.

When you set the coil up for the first run, it will at best be in
marginal tuning, that means that the resonant frequency of the primary
and the secondary cap/coil circuits are not quite equal. To bring the
coil into tune, resonnance, you then move the tap point, untill the coil
is in tune.

When you have got it into tune, you will probably want to make
alterations to the coil, in attempt to get longer sparks, and this can
be done by making the topload (toroid) bigger, which will lower the
resonant frequency of the secondary circuit. To make the primary circuit
follow, you then need to add turns to the primary coil, you tap
outwards. This will make longer sparks with the same power input.
Or you might want to increase the tank capacitor to a point where this
means that you actually have to decrease the amounts of turns on the
primary coil, even with a bigger topload.

As you will see, the tapping point, in conjunction with a primary coil
that has a generous amount of turns, is the key to obtaining initial
tuning, as well as allowing further experiments to be performed.

Hope this helps, 

Cheers, Finn Hammer

Tesla List wrote:
> 
> Original Poster: "Jeremiah" <jmeizis-at-metallicafan-dot-com>
> 
> ?  what does this mean?  What are some specifications, information etc.
> Thanks