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Re: Simulate!


    If you would like to take a look at what simulations can do to a tesla
coil take a look at these multiple resonant tank circuit readings, and the
basic schematic for it.

http://members.xoom-dot-com/suckyfish/melissa/6.jpg

    You see, I was messing with this software simulation of a circuit, and I
decided to make it do some hard and accurate math.  These are the results of
the software.

http://members.xoom-dot-com/suckyfish/melissa/5.jpg
http://members.xoom-dot-com/suckyfish/melissa/4.jpg

    I couldn't believe that I was only applying 24V AC, and getting between
kV peak to peak, and kV PP.  So, I did breadboard a facsimile of the
circuit, and it really did the same thing.  It was tough coming up with the
right capacitor values, and the right values because, it consists of banking
parallel values.  With time, and a few months of it just breadboarding I
figured this thing out to a T.

    It's all based upon frequency, ring values, and resonance.  This thing
fails the test if you're trying to charge capacitors, or using reactive
components but, as long as you stick with resistive loads, it kicks up to
the same outputs as the simulations indicate.

    I haven't displayed the chaotic technique which has an absolute average
output that would be straight off on 5 kV using the same step up, step down,
step up, step down arrangement as shown in the first schematic.  I can tell
the trick to achieving the chaotic output.  In the last stage, the capacitor
value is half of the resonant calculations value, or double the frequency.
The modulated output is the result of a phase difference that results from
how impossible it is to precision tune to tank circuits to exactly the same
frequency.  I have watched the simulation fall off in microseconds,
milliseconds, and up to a full second.  The closer you get to exactly the
same frequency on the primary, as the secondary the longer the delay before
the output starts to appear more natural.  The trick doesn't like to occur
at frequencies lower than 500KHz, and can be guaranteed at 1MHz.
Personally, I prefer a chaotic output because, the output power is averaging
to the maximum so frequently in the signal that you don't get a millisecond
into the signal before that average is maximum power out.

    It does work breadboarded but, it is a pain getting the capacitor values
to add up, and finding the volt watt rating for them.  Second, impedance
matching of the driver circuit is a must to the value of Xc, and XL in
parallel as if they were only DC values of resistance if the Oscillator is
going to start the circuit, and cause it to operate in the same fashion as
the simulation.  So, the right amount of current is a must to drive the
first stage tank circuit.  Personally I would use a collector output, and a
bypass capacitor of a large value with a emitter resistor of a value that
would be 2 times the impedance of Xc, and XL in parallel.  At this point a
good designer of oscillator circuits could build a better tesla coil using
this series of tanks in the design of the driver for the final stage.  I
have found that you will need parallel primary windings for the maximum
power output values.  I suggest that you wind the secondary first on a
phelonic core to step up the voltage on a 1 to 10 step up, and rely on
coverage of parallel primarys.  Which is like using ten times the same
diameter of wire for ten times the windings on a secondary, and ten primarys
being sure that your windings are all in the same direction to keep them in
phase, and make a point of it for yourself if you choose this project.

James.