### Author Topic: Resonance WFC  (Read 48716 times)

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##### Re: Resonance WFC
« Reply #32 on: May 09, 2010, 15:02:56 pm »
Update:

The dimensions of my resonance cell I have build...

free space permittivity = ?0 = 8.85 pF/m
length (l)    =    120     millimeter     =    0.12     meter = 4,72 inch
outer conductor diameter (b)    =    17     millimeter     =    0.017     meter = 0,67 inch
inner conductor diameter (a)    =    12.7     millimeter     =    0.0127     meter = 0.50 inch
Gap is 2.15 millimeter = 0.085 inch

Total calculated capacitance (C)     =     1.8305852039534E-9     farad  = 1.83nF
Got strange measurements when I used a LCR-meter! It measures 573uF in H2O tap water!
Can measurements be done using LCR-meters on a WFC? Also the resistance is not constant! Can we use the calculated values or the measured ones?

You can see my HV transformer and my Amplifier I want to use for the resonance cell. The Amplifier delivers 50Watt per channel 20V Vpp AC signal, so I can use 10 Vpp DC as a pulse signal going into the HV tansformer. (20-20kHz) The HV transformer is an ESL one step-up 1:125. Input resistance on the primary is 1ohm and sec 3k Ohms (input frequency dependent).

br,
Webmug

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##### Re: Resonance WFC
« Reply #33 on: May 09, 2010, 15:32:52 pm »
nice work, i read that the C meter will read the impedance of the wfc, not specifically the C, JLN shows a difference between his calculated and measured too, and he actually found resonance, apparently, maybe his results would be worth another read for you at this stage in the game, maybe get some more ideas.

Also, I'd be interested to see if you can reproduce mine and warps results on your delrin cell, because I found lots of em interference being thrown off the cell, the delrin is probably supposed to direct all that energy into the water gap.

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##### Re: Resonance WFC
« Reply #34 on: May 09, 2010, 16:36:04 pm »
OOOO MY webmug , I will warn you of something right now .

If your amp is the ab push pull type then you should watch carefully the commutation period between both waves with that large transformer . start with a high resistive load at first .

A transformer like that stores alot of energy , I have discovered that class a push pull transformer coupled with much static current is the only thing that will result in pure sine and not be affected by the bemf since its already conducting a large static current of lets say 700mA to 1 A , transformers only pass through the oscillations on the secondary and not dc , kinda like a coupling capacitor , but it will not be forced to throw out high voltage spikes if lets say the current goes from 1 A to 2 A at the max peak oscillation . The water itself it very resistant and always over 100 ohms , even with 6 large tubes in parallel in regular tap water .

Once those 2 transistors are at their transistion phase there is a time of very high resistance , and the transformer might give out a destructive pulse .

If you blow up that amp , Pm me and I will send you a design , it is not efficient but it is better for this type of application .
« Last Edit: May 09, 2010, 17:15:40 pm by Dankie »

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##### Re: Resonance WFC
« Reply #35 on: May 09, 2010, 20:53:43 pm »
WM,

I would go for the calculated C and not for what your LCR meter is showing  :-)
I seen the same on my meter.

Steve

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##### Re: Resonance WFC
« Reply #36 on: May 09, 2010, 22:06:02 pm »
Measurements are difficult to do on a WFC, I think I will go for the calculated one then...
I want this setup to go into resonance in 20-20kHz range so a choke L in mH range could work.

My idea is to connect at least 25W or more (4-8 ohms resistors) on the Left and on the Right channel at the amplifier output. (amplifier doesn't work if one channel is connected) Then connect to output channel (Left or Right) a diode (rated 3Amps) to make the sine wave signal DC pulsed. This will go into a HV transformer (1ohm 15-25Watts). Amplitude can be adjusted, going into the amplifier input.
Finally the signal would go into the blocking diode, choke and resonance cell.

My idea for a test signal going into the HV transformer could do AM modulation (gate) This on-gate signal does not fall to zero Vpp DC. So voltage amplitude would be present in the on-gate to keep potential on the cell. Off-gate signal is then Vpp max.

Isn't it so that the first diode (before HV transformer) could block/prevent a bemf from the HV transformer going into the amplifier?

br,
webmug

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##### Re: Resonance WFC
« Reply #37 on: May 10, 2010, 02:42:48 am »
Measurements are difficult to do on a WFC, I think I will go for the calculated one then...
I want this setup to go into resonance in 20-20kHz range so a choke L in mH range could work.

My idea is to connect at least 25W or more (4-8 ohms resistors) on the Left and on the Right channel at the amplifier output. (amplifier doesn't work if one channel is connected) Then connect to output channel (Left or Right) a diode (rated 3Amps) to make the sine wave signal DC pulsed. This will go into a HV transformer (1ohm 15-25Watts). Amplitude can be adjusted, going into the amplifier input.
Finally the signal would go into the blocking diode, choke and resonance cell.

My idea for a test signal going into the HV transformer could do AM modulation (gate) This on-gate signal does not fall to zero Vpp DC. So voltage amplitude would be present in the on-gate to keep potential on the cell. Off-gate signal is then Vpp max.

Isn't it so that the first diode (before HV transformer) could block/prevent a bemf from the HV transformer going into the amplifier?

br,
webmug

What kind of amp is this ?

Is the amp going to do a unipolar pulse ? aka relay type with pnp or n type mosfet . If so then yes it stands a chance of working since you can put a freewheel diode , no need for static DC.

But is you had the idea of puting  transfo from grround of supply to your push pull amp with true AC then No , this cannot be done  easily , perhaps a series parallel resistor or something , paralle resistor and cap .

but then resonance and noise gets multiplied a thousand fold ....

You never know enough about amplifiers to keep you prepraped for what problems are headin ur  way lol ....

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##### Re: Resonance WFC
« Reply #38 on: May 10, 2010, 15:38:53 pm »
Measurements are difficult to do on a WFC, I think I will go for the calculated one then...
I want this setup to go into resonance in 20-20kHz range so a choke L in mH range could work.

My idea is to connect at least 25W or more (4-8 ohms resistors) on the Left and on the Right channel at the amplifier output. (amplifier doesn't work if one channel is connected) Then connect to output channel (Left or Right) a diode (rated 3Amps) to make the sine wave signal DC pulsed. This will go into a HV transformer (1ohm 15-25Watts). Amplitude can be adjusted, going into the amplifier input.
Finally the signal would go into the blocking diode, choke and resonance cell.

My idea for a test signal going into the HV transformer could do AM modulation (gate) This on-gate signal does not fall to zero Vpp DC. So voltage amplitude would be present in the on-gate to keep potential on the cell. Off-gate signal is then Vpp max.

Isn't it so that the first diode (before HV transformer) could block/prevent a bemf from the HV transformer going into the amplifier?

br,
webmug

What kind of amp is this ?

Is the amp going to do a unipolar pulse ? aka relay type with pnp or n type mosfet . If so then yes it stands a chance of working since you can put a freewheel diode , no need for static DC.

But is you had the idea of puting  transfo from grround of supply to your push pull amp with true AC then No , this cannot be done  easily , perhaps a series parallel resistor or something , paralle resistor and cap .

but then resonance and noise gets multiplied a thousand fold ....

You never know enough about amplifiers to keep you prepraped for what problems are headin ur  way lol ....
Do not know the amp class. It's a car audio amplifier. It also can be bridged.

The idea is to connect one channel to a large resistor (at least 25W 4ohm) then halve rectify the voltage formed over the resistor (unipolar pulse). This is then going into a transformer.

Can this be done? If the transformer is connected in parallel over the resistor?
Am I thinking wrong here? (too simple )

br,
Webmug