Re: Ratio of primary outer dia.

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

Original poster: "Dr. Resonance" <resonance-at-jvlnet-dot-com> 


There is no "exact ratio" because the design depends on two factors, not
one.  These two factors include the primary inductance and the primary
capacitance.

Our procedure goes something like this:

First, more capacitance usually provides higher peak currents and more
energy available to couple into the secondary system.  Keeping this
important factor in mind, we tune as follows:

Using a "scrap wire" primary, usually 24 turns to 30 turns, we tune the
system with the size capacitor a computer program dictates.  Now, you have a
basic tune with fixed capacitance.

If you are in the range of 6-12 turns (with NST) or 3-8 turns (with pole
xmfr), you have a good, but not optimum capacitance.

Now, we tune for optimum capacitance by adding more capacitors and reducing
the # of primary turns.  Our final goal is 6-12 turns with NST or 3-6 turns
with pole xmfr.  A large capacitance value provides more peak current and
additional energy available to couple into the secondary system.

This "turns reduction" as I call it usually provides significant improvement
in secondary output (assuming your spark gap is up to proper quenching of
additional current).

If you increase the cap size you may also have to adjust your power supply
to provide more energy to charge the larger cap.

These procedure are time consuming but assist in the quest for optimum
output for any system large or small.

Dr. Resonance

Resonance Research Corporation
E11870 Shadylane Rd.
Baraboo   WI   53913
 >
 > Does someone have a rule of thumb for determining  primary outer diameter
 > based on secondary diameter and height?
 > I did an archives search, but came up with nothing definitive.  I am sure
 > that there is a ratio for optimum performance.  Also, if John Couture is
 > reading this, are you planning on publishing an updated version of your
 > construction guide?  Mine is from the early 90's, and I was curious if you
 > are planning to integrate some of the last decade's developments into a
new
 > book.  I certainly hope so.
 >
 > Thanks,
 > John Richardson