Tube cell reloaded

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Hi there,
now as i have a much better knowledge of electronics, semiconductor parts, circuits and calculating everything i have setup something again.
Made a tube ready (see pic) and built the vic circuit.

Unfortunately there is no superelevation of voltage at coils or cap.
The coil is around 0,2m long, bifilar wound with ferrite core (i believe). Gap of the cell is around 0,001m.
Diodes are 1N4007 (1000V,1A). One freewheel diode and the blocking diode.

Problems as of now:
- My selfmade signal generator using a mikrocontroller isn't stable, frequency is switching
- No transformer yet, the only one's i have is 12 V : 230 V
- don't know the capacity of the cell. Ohmic resistance is there, but also not measurable because it's not linear (draws 0,5Amps at 3,9V and 1 Amp at 5V)

Next steps:
- I'll connect the cap to 230V / 50Hz plug-AC and measure the current and then calculate the capacitancereactance of my cell at 50Hz
- I will use the transformer i have, the dude on hyiq.org did the same and it seemed to work for him.
- Also, I'll have to build another signal generator.

I'll be posting regularly

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alright.
frequency of the generator is stabilized a bit,
i have the transformer (12V:230V), which strangely enough creates sine-waves from square pulses. 12V in around 150V peak to peak out.
measuring that with the oscilloscope is fine, but as soon as the diode get's in it becomes 75V direct voltage. probably the diode is acting as a capacitor, don't know. frequency was 220kHz.
when connecting the tube cell there is no voltage at the cell and no voltage at the transformer, i guess too much power needed to have the voltage stable.
what bugs me most is that with the diode i cannot measure any pulses or half-waves even.

pictures to come

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alright.
frequency of the generator is stabilized a bit,
i have the transformer (12V:230V), which strangely enough creates sine-waves from square pulses. 12V in around 150V peak to peak out.
measuring that with the oscilloscope is fine, but as soon as the diode get's in it becomes 75V direct voltage. probably the diode is acting as a capacitor, don't know. frequency was 220kHz.
when connecting the tube cell there is no voltage at the cell and no voltage at the transformer, i guess too much power needed to have the voltage stable.
what bugs me most is that with the diode i cannot measure any pulses or half-waves even.

pictures to come

Looking forward to your progres and pics!   
My 2 cents:
You have a deadshort condition when you hook up the wfc to yr trafo....
When you measure the cells resistance, or when you do dc tests and you measure amps and voltage, you will know resistance.
Something like 1 ohm for a parallelcell or even less......
However...if you go from a 50% duty towards a 5% duty cycle, you might be able to pulse very short bursts and you prevend the current from going thru the cell.....


Steve

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My idea was similar. The resistance of the cell is very low (maybe even 1ohm as you said). Therefore at 75V dc it would need 75 Amps direct current. The transformer obviously isn't able to deliver 75A and thus the voltage breaks down to zero, similar to a dead short like you said, even if it isn't a real dead short.
I'll try the smaller pulses, duty cycle was around 40% at the moment.

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Pics:
(http://j.imagehost.org/t/0566/IMG_6969.jpg) and (http://j.imagehost.org/t/0622/IMG_6967.jpg)
Container with tube in it. Didn't have a better one or money for a better one. I put calcium in the water for conditioning (white insulating layer). Will probably wrap the inner tube with thin plastic. Brown muck is generated slowly, but nearly nothing anymore.

(http://j.imagehost.org/t/0039/IMG_6971.jpg) (http://j.imagehost.org/t/0633/IMG_6972.jpg)
PWM Generator, Multimeters, Bifilar coil, Transformer.

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Took some measurements today.
Coils are both 1,2mH, the cap without water is 4,2mF (!).
That means it built a resonance circuit for 50Hz without water, unfortunately with water the capacitance is > 300mF and the resonant frequency shrinks to 5Hz.
Damnit i never have thought that the capacitance can be too big. I hope the LCR-meter used the wrong method and calculated a much larger value :/

does anyone have a good way of measuring capacitance? my plan to use 230V grid voltage wouldn't work out that well, if the cap is really 4,2mF then it would draw > 250Amps at 230V. Not a good idea.


Update: had the great idea to use my 230V:12V transformer and measure reactance in series with 12 ohm resistor on the 12V side. Didn't work out as my cable on the 230V side overheated and broke in a second. Anyway i then took apart the tubes and dried them. The white coating already started to build nicely, but on the inner side of the outer tube.
I put everything back together dry again and this time my RLC meter showed a more stable value (no water) of 270pF or 0,27nF which is much more likely.
If insulated and filled with water the capacitance should be around 21nF +- 2nF and the resonant frequency in the range of 22kHz.

Update 2: Found out that RLC meters use direct current and measure how long the cap needs to be charged fully. Not the best method and it only works if it's absolutely sure that there is no charge left on the cap. So i think the 270pF is probably the more accurate value.

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I've read a lot of posts where people can't get the right capacitance, one thing i remember reading is that some instruments will measure the impedance and not the capacitance, and then people start talking about how the cell is a resistor as well as a capacitor and so on...

Your project is coming along good, I hope you find some results soon

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Some say you have to calculated the surface of the tube...

Steve