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Author Topic: partzmans board ATL  (Read 36180 times)
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Yes that is correct on both cases.  IOW, the 680pf charged to 64v is just 1.4uJ in stored energy.  Notice that even this small cap is barely discharged after C1 has reached 2.97v .

I'm using small jumper wires for most of the connections which is really not the best.  Short, soldered connections would be the best.

"Yes that is correct on both cases.  IOW, the 680pf charged to 64v is just 1.4uJ in stored energy.  Notice that even this small cap is barely discharged after C1 has reached 2.97V"

WOW!  Please let us know if you do more tests... 
and thanks again.
Steve
   

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Jon,
What you are measuring there is not the voltage across C1.  If you put a short across C1 your scope will see just the single turn output.  So even if there remains zero voltage axcross C1 your scope will measure that single turn value.  What would be interesting to see is how the single turn (no C1) waveform looks in comprison with your result here.  If it is identical then C1 has no voltage on it.  However the induced E field from -dA/dt would be expected to polarise the dielectric.  I would expect that polarization to yield some difference between the two measurements, perhaps maximised if the parallel plate capacitor were turned through 90 degrees.

In following your earlier work in this area where you had 4 turns each with a central capacitor, I am preparing a paper that shows how the induced E field polarization there does influence the results.  To verify that I am using the axisymmetric version of FEMM which is a true 3D simulation.  In effect FEMM simulates a ring of current of the dimensions of the ferrite ring core (thus like a superconducing magnet).  The current value can represent the ring core flux value Phi.  The H field from that ring of current then exactly models the A field around the real core.  Taken further the current value can represent dPhi/dt then the FEMM H field represents the -dA/dt E field.  This can be taken further by emplacing very high mu regions representing conductors or resistors where the magnetic reluctance value exactly models the real resistance value.  Can't model capacitors though, but this does give insights into what you are observing using just resistors.  The biggest problem is that whatever you put into the model in 2D actually is 3D around the axis, so a (almost) full single turn conductor is a conductive sheath over the whole core with a small slot around the outside.  A resistor in place of your capacitor would be two concentric cylinder electrodes with resistive material between them that in FEMM become two concentric cylinders of very high mu material with low mu material between them.  When you move this from outside the ring to inside the ring you have to adjust things to keep the resistance (reluctance) values the same.  I will have a go at this and report back.

Smudge
   
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Jon,
What you are measuring there is not the voltage across C1.  If you put a short across C1 your scope will see just the single turn output.  So even if there remains zero voltage axcross C1 your scope will measure that single turn value.  What would be interesting to see is how the single turn (no C1) waveform looks in comprison with your result here.  If it is identical then C1 has no voltage on it.  However the induced E field from -dA/dt would be expected to polarise the dielectric.  I would expect that polarization to yield some difference between the two measurements, perhaps maximised if the parallel plate capacitor were turned through 90 degrees.

Smudge,

OK, as seen in the pix below, C1 is positioned in the core with a shorted turn on the outside of the core connected across C1.  In the first scope pix, CHR1(wht) is the prerecorded voltage across C1 with the short in place and CH3(pnk) is the voltage across C1 with the short removed.  There is enough differential between the two measurements that would seem to indicate I am measuring a valid single turn voltage on C1.  The wave shape of the shorted turn voltage to me indicates that C1 is resonating with the inductance of the shorting wire and C1's own internal inductance.  IOW, if the short was ideal, we would see no voltage across C1.

In the second scope pix,  the positions of C1 and the shorting wire are reversed.  IOW, the shorting wire is now inside the core with C1 outside the core.  CHR1(wht) is the prerecorded voltage across the shorting wire with C1 connected and CH(pnk) is voltage across the shorting wire with C1 disconnected.

BTW, the position of C1 within the core seems to make no difference in the OC voltage across it.

Quote
In following your earlier work in this area where you had 4 turns each with a central capacitor, I am preparing a paper that shows how the induced E field polarization there does influence the results.  To verify that I am using the axisymmetric version of FEMM which is a true 3D simulation.  In effect FEMM simulates a ring of current of the dimensions of the ferrite ring core (thus like a superconducing magnet).  The current value can represent the ring core flux value Phi.  The H field from that ring of current then exactly models the A field around the real core.  Taken further the current value can represent dPhi/dt then the FEMM H field represents the -dA/dt E field.  This can be taken further by emplacing very high mu regions representing conductors or resistors where the magnetic reluctance value exactly models the real resistance value.  Can't model capacitors though, but this does give insights into what you are observing using just resistors.  The biggest problem is that whatever you put into the model in 2D actually is 3D around the axis, so a (almost) full single turn conductor is a conductive sheath over the whole core with a small slot around the outside.  A resistor in place of your capacitor would be two concentric cylinder electrodes with resistive material between them that in FEMM become two concentric cylinders of very high mu material with low mu material between them.  When you move this from outside the ring to inside the ring you have to adjust things to keep the resistance (reluctance) values the same.  I will have a go at this and report back.

Smudge

I look forward to your results.

Regards,Pm
   
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I'm going to jump ahead a little and share the details of a potential generator using DIvE or Dielectric Induction via the E_Field.  Apart from the dielectric induction, it has another unique feature in that the input energy required for L1 is taken from the output to Vload.  This is positive feedback due to the fact that at the instant in time when S1 closes and the voltage at Vc1 is imposed across L1, the voltage at Vc1 increases due to the dielectric induction.  This in turn increases the voltage across L1 which increases the voltage at Vc1, etc.  Since we are only utilizing the equivalent of two turns with C1 and C2 on the secondary, the positive feedback factor is small so runaway will not occur.  However, consider the possibilities if the output equivalent turns is greater than L1's turns.

The first pix is the schematic.  D2 clamps the voltage across L1 to ~ 0 volts after S1 turns off.  C1 and C2 are connected in series with wire on the outside of the core.  Vload is 64v DC and C3, located close the toroid core, provides bypass to negate the inductance of the power supply leads feeding the circuit on the bench.  R1 provides the current path to pre-charge the series connected C1-C2 to 64v DC.  D1 is the current path for the positive current flowing into Vload due to the increase in voltage across C1-C2 that is caused by the dielectric induction.

The second pix is the scope shot.  The trace ID is-

CH1(yel) = Switch S1 input
CH2(blu) = Voltage at VL1f
CH3(pnk) = Starting and ending voltage at Vc1 and the mean voltage both across C1-C1
CH4(grn) = Mean current flowing into Vload
Math(red) = Mean power of CH4*CH3

In this example we are going to measure between the vertical cursors before the voltage across L1 returns to zero.  If we allow the voltage across L1 to return to zero, the voltage across across C1-C2 will lower and that is not the purpose of this example.  What I hope to show here is the fact that energy is supplied from the outside to C1-C2 via dielectric induction with the obvious measured gain.  We will address the voltage across L1 at a later date.

So, from the traces we see an energy loss in C1-C2 (combined capacitance is .53uf) with starting and ending voltages of 63.92v and 63.22v respectively to be UC12=(63.92^2-63.22^2)*.53e-6/2=23.6uJ .

We also see that the power supplied to Vc1 over 2.344us is 100.7W for an energy UVc1=100.7*2.344e-6=236uJ .  Technically, the mean current through C1-C2 of 1.51A is feeding the 64v DC at Vload over the same time period so calculating this energy would be UVload=1.51*64*2.344e-6=227uJ .  This does not include the loss in D1.

Here we see COP's of 10 and 9.61 depending on which values one chooses to use.  Keep in mind that the input is taken from the output.

This is not the final solution for an OU generator but I hope the potential is obvious to those interested.

Regards,
Pm 


 
   

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Smudge,

OK, as seen in the pix below, C1 is positioned in the core with a shorted turn on the outside of the core connected across C1.  In the first scope pix, CHR1(wht) is the prerecorded voltage across C1 with the short in place and CH3(pnk) is the voltage across C1 with the short removed.  There is enough differential between the two measurements that would seem to indicate I am measuring a valid single turn voltage on C1.  The wave shape of the shorted turn voltage to me indicates that C1 is resonating with the inductance of the shorting wire and C1's own internal inductance.  IOW, if the short was ideal, we would see no voltage across C1.

In the second scope pix,  the positions of C1 and the shorting wire are reversed.  IOW, the shorting wire is now inside the core with C1 outside the core.  CHR1(wht) is the prerecorded voltage across the shorting wire with C1 connected and CH(pnk) is voltage across the shorting wire with C1 disconnected.

BTW, the position of C1 within the core seems to make no difference in the OC voltage across it.

I look forward to your results.

Regards,Pm

@Pm,

It is clear from the few comments here that many people do not understand the manner in which the dA/dt time-changing magnetic vector potential works to induce voltage hence also current into circuits.  The first image below shows the induction E field from a ring core carrying time-changing flux.  The size of the arrows indicate the magnitude of the E field so you can see how it changes throughout space.  FEMM only gives half the full plot, the blue line is the symmetrical axis and you can imagine a mirror image of the field plot for the other half.  Any closed loop that encircles the flux has an induced voltage around the whole loop that equals the volts/turn, but the voltage induction varies around different parts of the loop.  The E field applied to a conductor whose resistance is negligible will quickly transport mobile charges to one end leaving the other end having the opposite charge, so if the conductor encircles the flux the voltage will be seen at the ends.

The next image shows the situation with the capacitor outside the ring core with the scope probe across it.  The scope sees the full voltage across the C and the current is of a value to charge that C.  The next image has the C inside the ring core.  Here the scope still sees almost the full voltage across the scope probe capacitance but that is not the voltage across the C because a large part of that measured voltage is actually induced into the scope connections that encircle the flux.  A better method of determining the voltage across C is to integrate the current flow.  Alternatively to measure the induction into the scope leads that encircle the flux which I suggested could be done by shorting C so the scope then measures just the volts/turn, then subtract that from the previous measurement with the C in place.  I did not intend the short to be outside the core as shown in the final image where the scope is measuring the voltage across that external short.

Having said all that I can say that working with FEMM is discovering unusual effects that might lead somewhere.  This particularly applies to Pm's earlier experiment where the C inside the ring core is carrying charge from an external battery.  The division of the induction between the external circuit and the internal C is something that has not been properly explored AFAIK and is highly unexpected.  You will have to wait for my work to be completed on this and I cannot devote myself full time to this because my wife needs me to care for her.

Smudge         
   
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Smudge,

Thank you so much for doing this analysis! O0  I know how difficult and time consuming it is when a loved one is not doing well.  My prayers go out for you both.

I'm sorry I misunderstood where you wished the shorted wire to be.  I agree with you on the results in the position you stated originally.  However, from some of my tests I may be able to show
that there truly is a voltage across the capacitor in the core.  More later-

Regards,
Pm
   
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Smudge and all,

The general consensus from image 3 in your post #404 and from other comments I've received, is that the voltage as measured across C with the scope probe connected as shown in your image 3, is not the real voltage across C but rather represents the voltage across the 3.9pf probe capacitance.  I humbly disagree!   

I do agree that the scope probe resistance and capacitance provide the completed path for the dA/dt generated E-Field to C, but C is actually charged to the voltage measured by the scope which results in a real relative
energy in C.  I will show proof of this in the following data and images.

The first pix is the schematic test circuit for this demo.

The scope ID's are CH1(yel)=V1 voltage, CH3(pnk)=C1/Vc1 voltage, and CH4(grn)=L2 current.

"DCE Test Circuit 1" is a scope image of the circuit with just the probe attached to C1 which is positioned in the core.  We see the average voltage measured by CH3 is 2.907v .  L2 is disconnected at this time.

For the remaining two scope pix, L2 is connected between the output of Vc1 and ground by the mosfet switch M1 ~1us after L1 is connected between the 64v DC supply V1 and ground via S1 and S3.  The idea is to transfer whatever energy exists at Vc1 into L2 from this point in time to the end of the cycle at 4.916us.  This should tell us which capacitance is supplying the dominant energy.

"DCE Test Circuit 2" gives us the starting and ending voltages across C1 at Vc1 of 2.987v and 2.199v respectively.  So, the energy loss in C1 is UC1loss=(2.987^2-2.199^2)*.461e-6/2=942nJ .

"DCE Test Circuit 3" shows the current rising in L2 to a peak of 178.3ma at 4.916us.  So, from this measurement we can calculate the energy reached in L2 at this point in time as UL2=.1783^2*60e-6/2=954nJ .

We have added the output capacitance Coss in M1 of 100pf to the circuit plus there also exists the self capacitance of L2 which is 160pf that is connected in series with Coss when M1 is off.  This net capacitance is in parallel to the 3.9pf probe capacitance.  However, when M1 turns on, Coss is shorted, so only the self capacitance of the air cored coil L2 of160pf is in parallel with 3.9pf for a total net capacitance of 163.9pf.

Now, using the starting and ending voltages at Vc1 we can calculate the loss in this net capacitance as UCnetloss=(2.987^2-2.199^2)*163.9e-12/2=335pJ .

At this point, it is obvious C1 is supplying the dominant energy being measured.  C1 reaches this energy level with no apparent means.  Therefore, I stand by my position that this outside energy comes from the aether and offers us at least one opportunity to build OU devices!

Regards,
Pm     

   
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Jon, I just have to check. 
 In your PDF, the C2 was at 680 pF,  Pico-farads, right?
Where, 1000pf = 1 nano-farad.

I want to make sure I'm getting this right.

And now, above, 3.9pF  and 100 pico-farads -right?
Double-check, 100pF = 0.1 nano-farad. Right?

Those are very small capacitances...
   

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Pm,

You said
Quote
"DCE Test Circuit 1" is a scope image of the circuit with just the probe attached to C1 which is positioned in the core.  We see the average voltage measured by CH3 is 2.907v .
How was the probe attached to C1?  Your circuit suggests it is connected between ground and Vc1 in which case it is not giving the voltage on C1 as there is voltage induced into the probe connections.  I thought I made this clear in my reply #404  with my "Capacitor inside.png" image.

Smudge
   
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Jon, I just have to check. 
 In your PDF, the C2 was at 680 pF,  Pico-farads, right?
Where, 1000pf = 1 nano-farad.

I want to make sure I'm getting this right.

And now, above, 3.9pF  and 100 pico-farads -right?
Double-check, 100pF = 0.1 nano-farad. Right?

Those are very small capacitances...

Steve,

You are correct with all the capacitance numbers above and yes, they are small.  This is the point!!

Jon
   
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Pm,

You saidHow was the probe attached to C1?  Your circuit suggests it is connected between ground and Vc1 in which case it is not giving the voltage on C1 as there is voltage induced into the probe connections.  I thought I made this clear in my reply #404  with my "Capacitor inside.png" image.

Smudge

Smudge,

When I first discovered this, I thought that the open circuit capacitance placed in the center with no outside connections was, induced by the E-Field to a potential equal to the V/t.  This was wrong! I now realize that it takes a complete path for the C to be induced with potential.  So yes, I agree with you and your image #3 but my point is, the C is charged to the V/t potential even through the 10M resistance and 3.9pf capacitance of the probe.  This is not conventional.  If you contemplate my last two scope pix in post #406, where does the energy come from to charge L2?

Regards,
Pm
   
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OK, let's see if I can make this more clear!

Below are tests which IMO prove that there is dielectric induction in the E-Field which yields unconventional results.  Criticism is more than welcome!

First the schematic.  The 64v DC supply is applied to the L1 primary by switches S1 and S3.  We are therefore generating an E-Field of 3.2V/t.  We have C1 (1.06uf) placed in the core window and C2 (5.9pf) soldered to C1 and is first placed outside the core.  A scope probe will be connected to this arrangement as well as L2 (35uH) later on. 

A pix of this test arrangement is shown.

P1 shows the scope probe connected across C1 (which is inside the core) and C2.  We measure 2.945v mean across C1/C2 with CH3(pnk).  CH1(yel) is the pulse input to S1 and S3.

We now reverse the positions of C1 and C2 that is, C2 is now in the core and C1 is outside.  P2 shows the measurement results on CH3 of -151uV C2/C1 which is the basic offset of the channel.  So no output and little to no energy in C1.

Now we re-position C1 and C2 so C1 is now back in the core.  We also now connect L2 across C1/C2.  P3 now shows the measurement results of this configuration.  CH4(grn) is the current in L2 taken with aa current probe.  We see the starting and ending voltages measured across C1/C2 by CH3 of 2.982v and 2.425v respectively.  The loss across C1 (ignoring C2) is therefore UC1loss=(2.982^2-2.425^2)*1.06e-6/2=1.596uJ .

P4 now shows us with the CH4 cursor 'b' the near end current peak in L2 of 286.9ma.  This equates to an energy level in L2 of UL2=.2869^2*35e-6/2=1.44uJ .  The absolute peak current of L2 reaches 298ma so the final energy in L2=.298^2*35e-6/2=1.554uJ .

P5 shows the same as above with the scope probe removed but laying in proximity of the assembly.

Apart from all this, I don't know what else to say at this time!

Regards,
Pm 
   
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Here is one example of an OU generator utilizing Dielectric Induction via the E-Field.  This design takes advantage of the positive regenerative feedback from the rise in voltage of C1 at VC1 back to the input L1 at VL1.  With only 3 turns on L1 with 64v DC applied when M1 turns on, we have a resultant V/t~21. 

First the schematic is shown below with the scope probe designations.  Note that C2 is 5.2uf made up of paralleled mono ceramic capacitors for low loss.  L1 is also wound with 15-34 litz wire for low loss.  This arrangement is made with two 2" toroids stacked on top of each other to increase the permeability over one core.  The primary L1 is then wound over both with a resulting AL=14.8uH/N^2 where N is the number of turns.  This helps reduce the input current to L1 and thus the load requirement on Vload.   A pix of the device is seen below minus the feedback wiring for clarity.

The first scope pix P1 shows the mean power delivered to Vload to be 1.223kW over 1.66us.  Yes, the numbers are correct!  The energy delivered to Vload is UVload=1.223e3*1.66e-6=2.03mJ .

P2 shows the starting voltage at VC1 to be 63.81v .

P3 shows the ending voltage after the E-Field has collapsed (although it is ringing) to be an average of 37.98v .  From this we calculate the loss in C1  to be UC1loss=(63.81^2-37.98^2)*1.06e-6/2=1.393mJ .

Therefore, we see an apparent COP=2.03/1.393=1.46 .

I am not sure what the results will be if the secondary number of capacitors equal or exceed the L1 primary turns, but we are going to find out!

Regards,
Pm

 

 
   

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PM

i was reading in an earlier post #394 that you use there the TPP0500B probe as a load (10Meg / 3.9pF), but after looking at this video: https://youtu.be/Pk7pMguQDy4?t=374 i understand that those value's are only correct at DC or very low frequencies.

So i measured two probes the same way as in the video using the RF spring for ground and measured the following using my nanoVNA:

The frequency range of the nanoVNA was from 10kHz to 60MHz and the marker was set to around 1MHz:

TPP0500B probe (spec: 10Meg / 3.9pF) measured at 1.059MHz 25.1K / 5.9pF
P6139B probe (spec: 10Meg / 8pF) measured at 1.059MHz 16.3K / 9.2pF

See below VNA output traces which show that the capacitance stays fairly stable (but somewhat higher as the specs) right after the start range, but the impedance quickly drops considerably between start and 5MHz range to only a fraction of the specified 10Meg.

 
FWIW Itsu
   

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Pm,

You still haven't understood what I am saying.  To measure the voltage on the C inside the toroid you must connect the probe as shown in the image here.  Then there is no voltage induced into the probe connections The way you do it you are seeing the induction voltage, not the C voltage.

Smudge
   
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Pm,

You still haven't understood what I am saying.  To measure the voltage on the C inside the toroid you must connect the probe as shown in the image here.  Then there is no voltage induced into the probe connections The way you do it you are seeing the induction voltage, not the C voltage.

Smudge

Smudge,

OK, I see what you are saying about measuring the C with all connections from the scope inside the core window.  I have a pix of the results of this below.  Basically, I would expect to see no voltage across C if the leads were placed perfectly symmetrical in the core window.  Only if there is a difference in the lengths and positions would I expect to see any voltage across C.

I do not understand what you mean by "induction voltage" verses the "C voltage".  Perhaps you could clarify this for me.  I think you are trying to say that the voltage measured across C is not real?

My position is that any voltage induced quickly on C by the E-Field via any outside path such as the scope probe capacitance and resistance, is very real and accounts for real energy at the level of voltage reached.  I think I have shown proven this is my posts #406 and #411 but I'm very willing to be corrected.

Regards,
Pm   

   
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PM

i was reading in an earlier post #394 that you use there the TPP0500B probe as a load (10Meg / 3.9pF), but after looking at this video: https://youtu.be/Pk7pMguQDy4?t=374 i understand that those value's are only correct at DC or very low frequencies.

So i measured two probes the same way as in the video using the RF spring for ground and measured the following using my nanoVNA:

The frequency range of the nanoVNA was from 10kHz to 60MHz and the marker was set to around 1MHz:

TPP0500B probe (spec: 10Meg / 3.9pF) measured at 1.059MHz 25.1K / 5.9pF
P6139B probe (spec: 10Meg / 8pF) measured at 1.059MHz 16.3K / 9.2pF

See below VNA output traces which show that the capacitance stays fairly stable (but somewhat higher as the specs) right after the start range, but the impedance quickly drops considerably between start and 5MHz range to only a fraction of the specified 10Meg.

 
FWIW Itsu

Itsu,

Thank you for taking the time to do the VNA measurements as the results are enlightening! 

However, the capacitance and resistance changes with frequency that you show for the TTP0500B Tek probe, would have very little effect on the overall dielectric charging of a 1uf film cap that reaches 3v peak in 35ns.  The probe capacitance and resistance create a voltage divider with the 1uf which in this case reduces the overall charging by a minuscule amount.

The scope probe provides the completed path for the E-Field to allow the rapid charging of C via the aether.   I of course could be wrong and I'm certainly open for any criticism!

Regards,
Pm
   

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OK, I see what you are saying about measuring the C with all connections from the scope inside the core window.  I have a pix of the results of this below. 
Please contrast this method of VC1 measurement with the one you've been performing before.
   

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Smudge,

OK, I see what you are saying about measuring the C with all connections from the scope inside the core window.  I have a pix of the results of this below.  Basically, I would expect to see no voltage across C if the leads were placed perfectly symmetrical in the core window.  Only if there is a difference in the lengths and positions would I expect to see any voltage across C.

I do not understand what you mean by "induction voltage" verses the "C voltage".  Perhaps you could clarify this for me.  I think you are trying to say that the voltage measured across C is not real?

My position is that any voltage induced quickly on C by the E-Field via any outside path such as the scope probe capacitance and resistance, is very real and accounts for real energy at the level of voltage reached.  I think I have shown proven this is my posts #406 and #411 but I'm very willing to be corrected.

Regards,

Pm

I take it the pink trace is the true voltage across C1 now which is now only 8mV, so different from the volts you used for your C1 energy calcs.  Please redo the C1 energy calcs using this new voltage.

Smudge
   
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Please contrast this method of VC1 measurement with the one you've been performing before.

OK.  Below is a diagram comparing what I call "Cullwick vs Dielectric Induction".  I use Cullwick for the internal connection method as that follows his 'on axis' method of measuring for his paradox inside the core window.

With the internal connection, both the "Z" and "C" see the same E-field potential.  Therefore between like potentials, no current will flow thus no opportunity for any aether flow into "C".

With the external connection, "C" is subjected to a higher density of E-Field when located in the core window than "Z" located outside the core.  Therefore current flow is possible between the differing potentials allowing the flow of aether into "C".

Regards,
Pm
   
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I take it the pink trace is the true voltage across C1 now which is now only 8mV, so different from the volts you used for your C1 energy calcs.  Please redo the C1 energy calcs using this new voltage.

Smudge

OK.  The energy calculation is now UC1=8e-3^2*1.06e-6/2=33.92nJ . 

What I'm failing to see is how this relates to my measurements in my experiments.  IMO, this is comparing apples to oranges and I reference my response to Verpies in post #419.

Regards,
Pm
   

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OK.  The energy calculation is now UC1=8e-3^2*1.06e-6/2=33.92nJ . 

What I'm failing to see is how this relates to my measurements in my experiments.  IMO, this is comparing apples to oranges and I reference my response to Verpies in post #419.
Yes it is comparing apples with oranges as you did not do what we expected.  Perhaps the image below will help.  This suggests an experiment as per your Culwick where the scope measures two voltages, Ch 1 is across your C and Ch 2 is across your Z.  Now you can rotate the ring core to 3 different conditions, first with C inside the core, second with neither inside the core and third with Z inside the core.  In all three positions the closed circuit encircles the core flux.  What I expect to see is a current pulse induced into the closed circuit of C and Z in series (you could even use your hall probe to get that current) yielding different voltages across C and Z.  And you get the same readings for all three different core positions.  Note that for the first core position Ch 2 is giving the voltage across Z but in your previous experiments you insist this would be the voltage across C.

Smudge
   
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Yes it is comparing apples with oranges as you did not do what we expected.  Perhaps the image below will help.  This suggests an experiment as per your Culwick where the scope measures two voltages, Ch 1 is across your C and Ch 2 is across your Z.  Now you can rotate the ring core to 3 different conditions, first with C inside the core, second with neither inside the core and third with Z inside the core.  In all three positions the closed circuit encircles the core flux.  What I expect to see is a current pulse induced into the closed circuit of C and Z in series (you could even use your hall probe to get that current) yielding different voltages across C and Z.  And you get the same readings for all three different core positions.  Note that for the first core position Ch 2 is giving the voltage across Z but in your previous experiments you insist this would be the voltage across C.

Smudge

Smudge,

OK, here is the test you detailed and the results.  First you are correct in that the results of the scope measurements are the same for all three core positions.

First is a pix of the test setup you required.  The 'C' in the core is a 1.06uf-2% film and the 'Z' is a 680pf-5% mica.  The current probe seen at the top of the toroid is measuring the current between 'C' and 'Z'.  The CH2(blu) probe is measuring the voltage across 'C'.  The CH3(pnk) probe is measuring the voltage across 'Z', and the CH1(yel) is the mosfet gate signal used to drive the primary of 20 turns which is connected to a supply of 32v.

Next is the first scope pix that shows an avg voltage across 'Z' of 1.478v and an avg voltage across 'C' of 4.381mv. 

Next is the scope pix of the current measured between 'C' and 'Z' which is seen to be 9.615ma rms at the rising edge of CH3 but essentially zero during the main portion of the cycle until the falling edge of CH3.

At first glance, these results appear to show that 'C' really has no voltage across it while 'Z' does.  This would be proving that the voltage I'm measuring across 'C' in my experiments is not real! 

Well, I disagree!  Here is my analysis of this experiment.

The voltage across 'Z' is real but where is it coming from?  As you yourself have shown via FEMM, the E-Field magnitude outside the core is far less than in the core hole.  So what we have is 1.478v on 'Z' but near zero on 'C'!  Should we not see current flow in the probe that is measuring between these two potentials?  I think so.

So why does 'C' measure near zero volts?  Because the E-Field influence on the CH2 probe that is the core center hole is equal and opposite the true voltage across 'C'.  IOW, 1.478v does truly exist across 'C' and the tip of the probe "sees" this positive voltage, but the lower part of the probe exiting the hole in the toroid is at a near ground potential.  This is because the section of the probe in the hole has the same potential across it as does 'C'.  Hence, the scope sees zero voltage.

So, the voltage potential across 'C' and 'Z' is equal and that is why we see no current flow between them.  Also, 'C' is the voltage source for 'Z'.

Regards,
Jon



 
   

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As you yourself have shown via FEMM, the E-Field magnitude outside the core is far less than in the core hole. 
The E-Field magnitude at a single point in space does not determine the measured voltage.  Rather it is the contour integral of all these E-Field vectors summed up along the measurement circuit.
   
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The E-Field magnitude at a single point in space does not determine the measured voltage.  Rather it is the contour integral of all these E-Field vectors summed up along the measurement circuit.

OK, my lack of understanding field vector analysis is showing.  So, the sum of the E-Field vectors is greater in the hole of the toroid between the top and bottom surfaces than on the outside of the core between the saame surfaces.

Pm
   
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