### Author Topic: My new approach  (Read 62545 times)

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##### Re: My new approach
« Reply #424 on: May 07, 2024, 09:15:55 am »
So now how can we couple the bifilar resonant coil that is now around the cell to the Vic magnetically?

Well that’s a very simple question!!!

Well we simply make another primary around it and put in parallel with the primary of the Vic!

Or we place the Vic coil very close to it and put a gap on it

So the bifilar coil resonance will be excited directly reducing the needed current thru the cell another step further

Or increasing if we kind of want to revert the polarity

Adding a variable coil between the primary and the primary we can than have a manual adjust of this coupling!!!!!!!!!!!

This is getting so interesting that I’m not stoping until is working!

Now you see that we have the same schematic of the Vic?

From the image you see that I’m using a cable as the bifilar… I hope the resistance is not too much … this cable has a magnet wire in it I mean it glue strongly to a magnet however the resistance is not as high as stainless steel I guess

Is a kind of cable made for sensors it came with this labview cdaq stuff I believe was for the temperature sensores thermopair

« Last Edit: May 07, 2024, 10:12:05 am by sebosfato »

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##### Re: My new approach
« Reply #425 on: May 07, 2024, 23:13:13 pm »
My hand hurt some winding so many turns…

I took a foil of brass inside a acrylic cup  and I will mix graphite with epoxy to have a variable resistor

Hope it works.. the idea is to have a resistor that can value with some wide range and be able to dissipate some power from the mismatch

I’m considering that the bifilar will behave as a kind of quarter wave or hopefully a 1/2 wave transformer ….
Because it would make a impedance output equal to the input and it seem that makes things simpler

A quarter wave would on the other hand provide impedance transformation making the voltage increase more and more as water became more resistive

Not sure only testing will show the way

So I going to use the usual technics to calculate the impedance based on known conditions

« Last Edit: May 08, 2024, 00:30:01 am by sebosfato »

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##### Re: My new approach
« Reply #426 on: May 08, 2024, 01:59:31 am »
To find the inductor that would produce the opposite phase angle in the same case (5kHz frequency), you can use a similar formula, but with the reactance of the inductor:

Phase angle (θ) = arctan(2 * π * frequency * inductance)

Since we want the opposite phase angle, we can set it equal to the negative of the phase angle produced by the capacitor:

-10.41 = arctan(2 * π * 5000 * inductance)

Solving for inductance:

Inductance = tan(-10.41) / (2 * π * 5000)

Inductance ≈ tan(-10.41) / (2 * π * 5000)

Inductance ≈ -0.0186 H

So, an inductor with approximately 0.0186 H (Henries) would produce the opposite phase angle of -10.41 degrees at 5kHz.

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##### Re: My new approach
« Reply #427 on: May 08, 2024, 16:11:31 pm »
I did first some tests to find the coil arameters

It has around 360 turns divided into 15 layers of bifilar

2,8mh each 4nf between them and one have 33 ohsmns and the other 132

When connecting to dc I could it 40 watts easily and it would heat up slowly some 50 degrees above ambient temperature with no ventilation whatever

The magnetic field is a little deceptive

From the inductance I can see that it will not have much high voltage and that indicates also that I need more turns and less space occupied

So I better find a copper bifilar with very tiny wire or simply make some cavities and wind two wires at once (pair twist)

Also I could make some tests with different coils and the thinner the wire the higher is the magnetic field per watt!!!

I think the ideal inductance would be around 80mh so the current needed to generate a magnetic field will be within the Range of the wire and also the voltages in it will be satisfactory and most importantly the magnetic field will cost less power and be more concentrated!

The same magnetic field a 18awg wire does consuming 500 watts the 29awg does the same consuming 59w

This coil I just did would have a reatância of only 87 at 5khz meaning I would have 174 v for 2 amps in resonance

Would be better to have a 2500 ohms with a ,3 amps giving around 800v

This is where design come into play

Meyer eft his drawings of acol with many cavities and tha is to may maximize the magnetic field and not simply for high voltage isolation

I put together some formula I’m using

Also don’t forget meyer use brooks coil formula on the techbrief

That is a coil for audio best know for having the maximum inductance possible geometry

Now come the nice part put this into resonance to try seeing any amp restriction

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##### Re: My new approach
« Reply #428 on: May 08, 2024, 23:40:49 pm »
I did some calculation it seem that the goal is to have 3  coils having 5k turns 170,5 ohms each 3mm spaced apart

It will weights around 1kg

The field will reach 1tesla with 0,5 amp peak and it has 1,9Henrie

The cell poses a short circuited turn so we can expect that value to be smaller

30mm brooks design

The main objective of this is to keep inductance some what small and also the self capacitance of the coil

Why?

Well we need it to be workable in the kHz range and if we have it self resonating beliow the frequency we want that is a problem if it’s above we can aways put a capacitor in parallel but if not will be necessary load the coil

When we split the coil into cavities in air we reduce the inductance

We reduce the capacitance

And we increase the magnetic field and frequency range

So basically we can also put this coils in parallel if needed !

Or they can be pulsed in a special sequence for example like 3phase

The thing is that this coils will be at high voltage level

A thinner wire could be used for the second coil for example 36awg or even thinner as the input current will be very small

So would be a bifilar but with two dissimilar wires

In this case it can be on another cavity for isolation the important is to maintain the same level of care to keep the capacitance small

It just need to have the exact same voltage induced as the big coil

That is important to be able to make the Vic work allowing the feedback to be clear

Im sometimes feeling like if I was macgyver kkkk

Hope you are all following on YouTube because I’m posting something’s there too…

I will start to make it hard to understand very soon because it’s going to get more complicated and I’m going to have less time to do it

I’m very happy that I’m finally finishing this projet wish my dad was here to see it!

Hope we are not wasting our time

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##### Re: My new approach
« Reply #429 on: May 09, 2024, 09:09:35 am »
Ok so this is the scenario

Capacitor 10nf coil 2,8mh resistance 33ohm resonance 30khz wavelength 2,5cm half wave reactance 527

Coil 360turns bifilar 1amp causes 33w power loss this is not copper

This voltage is only the resonant voltage

Quality factor will be lower than 10 probably because the electrodes act as a short too

I’m hoping that can increase the field near the electrode but is just a feeling

If we need this to be series resonance to the input we need the input circuit to have the remaining inductance since the
Bifilar cancel out most of the inductance and so you are charging the capacitor

That mean that for correcting the timing the input inductance the Vic I mean must have that specific inductance and so

Applying 33v should give 1 amp in series resonance if we would exclude waters resistance and the other coil

So my educated guess is that it will be charged with high voltage instead

The equivalent voltage you need to apply is that of the resonance you wanted and this is why thT value is important now

The voltage is a indicator of the fields when across the coil only

So the secondary can have maybe 2000v for full power

I have 45 turns primary coil that makes my 900 turns coil perfect for the task 20:1

And I can go little higher and put 150v to the primary

The coils will fry ?

Certainly haha

But the idea is that it can get a good test

The idea is to try to first zero in the current with the cell when driving the circuit without the cell in series

Driving only the resonance by other means like making a few turns and drive it in series while leaving the rest of the circuit connected

So we can add resistor inductor whatever needed

With that will be possible to go and check the ultrasonic for any feedback

Luckily my cell can be tuned but probably that frequency will be somewhat too high and so the wave length incompatible with the size of my electrodeszzz

Hope you get the idea

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##### Re: My new approach
« Reply #430 on: May 09, 2024, 16:00:39 pm »
I had to fix the gate circuit befor proceeding as it was causing a audible noise that could be heard on the speaker video

To solve it added a 2,2kohm resistor from VCc to the output of lm393

And a capacitor from its output to the positive input

Is working as a negative amplifier having a 10k pot for the duty cycle and 5k forming a divider to the vcc amd another to ground

Fucking autocorrection

The negative input has a 10kohm coming from the 555 ramp wave

Now the wave is perfect and I can proceed

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##### Re: My new approach
« Reply #431 on: May 10, 2024, 06:37:25 am »
I spend the day testing

Actually the circuit is capturing noise above some power level

Specially using the dividers probably because I have long wires

More than ever I want to make the pro pcb

I found better way to generate the scanning signal using only the 555 timer

Working on 5v s not so easy we need amplifier with rail to rail and I could not found a reasonable price

So I’m using the signal from the 555 ramp but I will manipulate the threshold by setting the control voltage and the trigger by adding some diodes

So it goes from 1 to 4 v without need of opamp

The pll give a very noise result when pulsing hard

It seem even the gate start to get cray

It may need a complete enclosure to be operable

Also need to look e into the filter capacitors

Is possible that I will need to add a different one for each range

If any of you want to have a pro pcb with this circuit send me now 50 dollars

I will make 5 pcbs for me and one can be yours with this preorder

If you want to wait to see it ready will cost 150 -200 dollar / euro

After I place the order for the pcbs the value will be raised!

This is simply for the costs and work done if you don’t value it your opinion isn’t valuable  too.

Send me inbox to get instructions please!

The boards will be arriving at your home in 2 or 3 weeks

I will try to send direct from china to you the board so it don’t need to come to Brazil and pay taxes here first

Anyone want to have it?