U core vic

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well... this is my first try at the U core vic
I couldn't find anything close to the core size Stan was using. Has anyone found one?
Anyway, The secondary and both inductors are 2000 trurns of 29g wire and the primary is 100 turns of 24g wire. The core is ferrite and has a high permubiltiy. I had a miss calulation and it came out with inductors four times the size that I wanted! So I recalculated my resonant frequency. It should be resonating around 1000hz but the highest voltage I get is around 20k and the frequency is half that at the cell. I calculated resonance with the possitive inductor values and water cap values. The highest voltage I can get is around 240 volts at the cell with 12 volts input. I'm still using my old tube cell which is 4 times too big. I'll have my new tune cell done soon, as close to Don's spects as possible.
Anyone have any advice why it doesn't resonant properly? or anything else I can change to get this working properly?
 

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here is my coil winder for those that were intersted, it makes things way easier but it still takes forever because I don't have a wire guide

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well... this is my first try at the U core vic
I couldn't find anything close to the core size Stan was using. Has anyone found one?
Anyway, The secondary and both inductors are 2000 trurns of 29g wire and the primary is 100 turns of 24g wire. The core is ferrite and has a high permubiltiy. I had a miss calulation and it came out with inductors four times the size that I wanted! So I recalculated my resonant frequency. It should be resonating around 1000hz but the highest voltage I get is around 20k and the frequency is half that at the cell. I calculated resonance with the possitive inductor values and water cap values. The highest voltage I can get is around 240 volts at the cell with 12 volts input. I'm still using my old tube cell which is 4 times too big. I'll have my new tune cell done soon, as close to Don's spects as possible.
Anyone have any advice why it doesn't resonant properly? or anything else I can change to get this working properly?

The AWG of the VIC inductors are all the same and the Sec, choke1 and choke2 have not equal wire length.
What high permeability value are you talking about? And what are the core specs?
If you have Unipolar Pulsed voltage at the secondary you are in business.

Br,
Webmug

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Nice winder

You have a very nice VIC build, Dave!
Maybe you can add a resistor between your cell and VIC.
Question: How many tubes you have hooked up to the VIC?
Its 1 VIC per tube, accoording to Stan and Don.

Steve

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This is a very nice build. It appears that when i did the photogrammetry on the VICs that the
coils had more of a random wind.  If the value of the inductor is  too large consider using whatever tubeset you have but use another capacitor in parallel/series to alter the frequency of the LC circuit
 
regards

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Thanks everyone for the replys and compliments!
 
Webmug, You are right! I should have specified; my chokes are 2030 turns and 1900 turns and the secondary is 1950 turns. I wound a primary of 29g wire but it doesn't work very well, I need to wait for my new bobbins to come to make another one. Permubility of the core is 2000. Here is all my info on the core. How can I detect a unipolor pulse? my scope is still not working
 
 http://www.surplussales.com/inductors/pdf/ich-ui-1f4.pdf
 
http://www.surplussales.com/inductors/pdf/ich-ui-1f4.pdf
 
Steve, thanks! It took some time. I'm only using one tube set. I'll add a resister and see what happends
 
Jim, Thanks as well! Don said that too, I just thought they may work even better if they were as close to perfect as possible, and i've been adding caps, I can get high voltage across the caps but it doesn't raise the water caps voltage, so far
 
 

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I've pretty much finished all the testing I will do with my current setup. nothing out of the ordinary to report. I can't get it to resonate properly or achieve the voltage I would like across my water cap; I will test it again as soon as my new cell is finished. This new cell will be built as close to dons specs as possible, I haven't been able to find a ss tube with a .030" wall. The closest I can find is .028", has anyone found something better?

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your not getting resonance because your cell has too much current leakage.
I would hazard a guess that your using tap water? Or water with too many impurities. The impurities act like electrolyte lowering your cells resistance. This is all the current in your cell traveling through like it is a resistor rather than a capacitor.
In SM's notes there is mention of different types of water and their amp draw. If possible increase your amp loading on your primary. How much to increase it by is hard to tell but once you hit the point where the amps can't pass through your waters resistance it will bounce back (increasing voltage) and try on the next cycle.
Remember your equation for resistance is "R=V/A"
As i see it, your cell will resonate, increasing in voltage, until it has built up enough volts to allow the applied amps to transfer through the resistance (water). So if your cell will allow your applied amps (note that your applied amps is the OUTPUT from your VIC) to transfer through your cell at 120V then that is your voltage point.
To fix this (as per the above reasoning) you will need to INCREASE your cells resistance, or INCREASE your amp output from your transformer. Just a bit of IMO