I checked tuning and it was spot on.

also reconnected the load, and saw the load when properly connected, does indeed damp the magnetic current at these low settings
I used it bit more psu 1,4V

I feel if I push up the power it will show the right phase for voltage and current again

yes phase is now good.
pushed to higher voltage psu 1,72A 2.4V
If I go higher, the disruptive event comes back. so for now, I need to keep the drain voltage under 180V
which is fine.
but the HV must really increase a great amount.

lets connect the center tap again, and see if there is a difference, so I can let it go

1.76A 2.6V psu (seems I can go higher in voltage, with the same current and output, previous 2.3V)

this is with the bifilar series connection used and probed.

voltage is a bit higher, and still stable with 200V on the drain.

is the green curretn lower?

phase is as expected, so the load was definitly not proper connected at the previous tests (and video recording)

zoomed into the current spikes. it looks like it first becomes negative.
current is definitely wrong in phase.
should I reverse the coil,
or reverse connect it?
NO I am just probing the wrong side of the coil again....

nope other side has the same current phase :shocked:
I think those current probe distortions should not be taken for accurate measurements of polarity.
They are just an indication of the strong dV/dt and displacement currents.

Phase is good.
displacement current and magnetic current are now fully in phase when loaded.
when unloaded, the voltage and currents are 180 degrees out of phase.

I had disruptions again at lower voltages. only 120V @ drain now. psu 1.5V

So both sides of the HC coil have the same currents and the same polarity, when the center tap is used.

I would call this true parallel resonance, as the capacitor is fed from both sides with equal amounts of current, with the same polarity.
I still dont fully understand how that works.

but. if the bifilar current coil has simular currents at both ends, then if they are induced by the displacement currents, the magnetic currents must flow in both directions simultaniously.

when looked at from the center tap, one winging is clockwise, while the other is counter clock wise. so that explains how this is possible.

Still is the current correct with a unifilar coil? yes it is. when it is connected on the left side.

This is the design plan for the new AC high voltage transformer.
a single or dual iron core toroid, inside the tesla coil, at the same high of the primary, to provide more inductance, so the coil can be kept small, while also at a low frequency (65kc/s)

iron core, and primary are movable. this should provide a disbalanced output, which still is out of phase.
the lower voltage is for the mosfet, while the much higher voltage is for the extra coil (HV coil)

Since I had everthing I needed, I tested the Idea.
and it doesn't work.

Yes the output is less.
but the freqeuncy is also different, since the smaller coil end, now has less inductance, and thus has a much higher resonant freqeuncy (blue)
damn...

I m going to reverse the coils, meaning the AC hv coil and MOSFET and ground will be on the other side.
see picture.

connected as previous post.
HV coil bifilar series connection not used,
AC and Drain connected to one side of the parallel capacitor.
all looks good at low levels.
load not connected, but load coil is grounded on the resonant side of the HC coil (opposite side of mosfet)

Seeing those large signal swings on the orange need to be fixed.
it is the signal from the delayed tl494 to the gate of the mosfet.
10x larger then the drain but same.

let see how it behaves under load.

swapped and under load.
green current phase has shifted -90 degrees as it always does. which is good.

now to fix those spikes...

90V on drain, with 510V loose probed on the HV coil...  also still a problem

nice
went up to 250V
no disruptive event, altough audio cut out again.

system was still grounded, which i now removed

so the challenge still is this.

I need thousands of ac volts
to charge one plate of the hV coil capacitor.

the other plate needs to be low enough in voltage to be swichted to ground by a mosfet.
(900V max but better lower)

the low side now is out of phase, but maybe it also could be in phase.
not sure how that would drive the parallel resonance.

so my AC high voltage transformer gives equal amounts of very high voltage on each end of the secondary

could I transform one side to a lower voltage?

if not I might need to make a new coil.
with much higher capacity so it will work with lower voltages.

I would need much larger tubes, with more length and diameter.

hmm

ac resonant high voltage transformer with hV primary, and low voltage secondary ?
would need capacitive coupling again.

wrap a wire around the HV lead and use that?
More surface area would bring the voltage down.

wire would need to be shorted out so it would not behave as a coil but as a plate.

I am going to wrap some copper tape around the isolation of the hv lead
the larger surface area should lower the voltage for the mosfet

just like the mantle of a coax cable.

I made it from two candle holders. 4cm diameter.
copper tape.
wire of the AC HV transformer through the middle.

Now the frequency has shifted up, which is ok.
to around 45kc/s
This is due to the parallel capacitor now being reduced in size, by this series capacitor.

one problem, is that somehow the AC HV transformer now starts hissing, and wont produce high voltages.

Another thing is that the low voltage side, now is 180 phase shifted.
But that is actually good. this will cause the field to increase voltage, demanding a charge current from the ambient.
like a vacuum, due to the sudden voltage increase.

sadly there also is a lot more ringing.

The voltage also cant get much higher.

At least I also found the probable anomaly cause. This happens when the signal delay on the edge of its capabilities.
I needed to retune the delay signal because the frequency is now so much higher.

Finally, I need to reduce the parallel capacity of the HC coil, to again match the new higher resonant frequency.

Since I have a dead line,
and this demands more engineering, I will stop the quest for now.

The ideas are always good, but again and again lead to more engineering challenges.
step by step I will get there.
I have come this far!
I will resume is time is available again

I found a working solution to reduce the voltage on one side of the AC transformer.

I placed a 15k ohm resistor is series to neutral.
This cable is also close coupled to the cable to the drain of the mosfet, to reduce ringing.

I tested with the drain connected.
blue shows the reduced voltage.
it is somehow slightly phase shifted.

this is with the load connected.
previous post only output coil was earth grounded. one side open ended
now it is grounded and connected to load

already much less ringing, I will tape down the neutral to the drain lead.
only the current probe shows high ringing at the discharge which is to be expected.
but also (not visible here) inn other segments

3.2kV with 110V drain
nice!

nnow why is it what shifted with the 15k resistor? would it have enough capacity/inductance to cause this?

I want to reverse the high voltage coil and see if it works.
if not I will revert back to my pancake coils.
like in my experiment of last summer

Using the AC high voltage tranformer to get the  voltage up, while the pancake coil acts as the capacitor plate extra coil, this time agian reversed / flipped over

load is to be rectified so one half of the cycle can collect energy while the other half loads it down.

But first a bit more rest.

I tried solenoids
but they dont work as needed
and I understand why.

the trick to mix the displacement current with the magnetic current is much easier with a pancake coil.

with a solenoid the two currents are 90 degrees separated not in phase but in direction.

it is due to the way the coils are capacitive coupled, which is related to which direction the displacement current is flowing in relation ship to the direction if the magnetic current (energy flow).

the hard to wind high voltage solenoid was done to create a change in direction of the displacement current.

but with the pancake coils, the direction of displacement energy flow is in the same direction as the magnetic energy flow.

IF one of the two pancake coils is 180 phase shifted or flipped over.
this is because these two energy flows are opposing in nature. so to get them to work together they need to be flipped on one side

let me explain it simple.

using capacitive coupled solenoids is like pushing a swing from the side

while a capacitive coupled pancake coil is like pushing a swing from the back

the push is the high dV/dt in combination with the capacity

and what is being pushed is the magnetic field, the magnetic current which is amplified by the displacement current .

this is another eureka

And then I can use the high voltage primary to create the impulses to fast charge  the dc offset capacitor.

using only one mosfet.

the question then becomes,
is the discharge at the right point?

well it should be. or else the HV coil phase should be flipped ,which is easily done by reversing the polarity (which side of the secondary is grounded)

single mosfet no delay
would it really be that easy?

input power 4.92A 10.3V =50.7 W
Fres=22.2 kc/s
33.2A pp (inside rim)
5.9kV pp (1cm distance air probed, so actual voltage is much higher maybe 15kV)
in phase
 :cool:

Welcome to the edges of mathematics, physics, and beyond.  Using a series of circles to approximate a Square Wave
https://twitter.com/pickover/status/1778766761615143082

Tesla’s Spark Gaps
https://www.facebook.com/photo/?fbid=1675830886156962&set=a.134555690284497

This website allows you to draw your own fourier epicycle drawings
https://www.myfourierepicycles.com/

if water electrolysis is a resistive load it would be an interesting way to convert power.

I wonder how constant the resistance is.
would probably depend on the concuctivity of the water.

so it could be tested with a soda solution.
the produced gas would need to be replennished with water to keep the solution in equal concuctivity.

then tested at different voltage levels to see if the resistance is constant

I placed my load current probe away from the coils at 54 cm.
used 33 240W halogen measuring 5.5 ohm cold
F res= 26.3kc/s
current does show some fluctuation when I add a 1uF (960nF) cap to the hc coil
no output.
HV tuned to max V just below ozone sizle

even bigger load, would lower cold resistance.
need to check load voltage