Bifilar pancake coil overunity experiment

[Void]

OK,how easy is OU to achieve ?
Easy
First take your bifi coil.
Set up as circuit below--secondary open.
Crank FG up until more power is being returned to the FG by the bifi coil,than the FG is delivering.
First scope shot at 1Mhz
Second at 9Mhz-->OU  . I mean,the calculated power has gone negative   
Brad

  Hi Brad. As I mentioned earlier, I have also seen conditions where my scope measures phase shifts > 90 degrees
between the input voltage and the input current, but chances are very high of course that the scope is not telling the truth. 
Phase measurements with this type of circuit at higher frequencies like that can be not very reliable at all. One way to check for
this is if you move the leads for the scope probes all around does the phase measurements shift around? If so, then your scope
is not making reliable measurements. Either way, I think the chances are very high your scope is not reading at all correctly.

[tinman]

  Hi Brad. As I mentioned earlier, I have also seen conditions where my scope measures phase shifts > 90 degrees
between the input voltage and the input current, but chances are very high of course that the scope is not telling the truth. 
Phase measurements with this type of circuit at higher frequencies like that can be not very reliable at all. One way to check for
this is if you move the leads for the scope probes all around does the phase measurements shift around? If so, then your scope
is not making reliable measurements. Either way, I think the chances are very high your scope is not reading at all correctly.

The very reason i carried out the test 
To show that in some cases,the scope will not show you what is actually going on.

As you can see in the scope shots i posted,any degree of phase shift is quite easy to achieve.
You will also note the voltage and current waveforms show very little offset,and are quite clean and stable,but the math trace is completely negative at 9MHZ.

Between 3 and 9MHZ,the circuit has a negative impedance value.
In the theoretical world,this would mean that the coil/inductor has become the source,and the FG has become the synk.
But in the real world,we are taught that this cannot be,and so there is an error some where.


Brad

[tinman]

Some details on the measurement method.

The initial method with the ground connected to the other R2 terminal is not bad in itself. We just have to understand what we're doing. The R2 resistor is not part of the device. Normally R2=0 and the output power Pout is only CH3²/R1. The input power is P=CH1*I where I is the input current.

Now how do you know the input current? This is where R2 is added, between the ground and the rest of the circuit. The voltage measured at the R2 terminals give us the current through the virtue of I=U/R, and this voltage is assumed to be negligible, without affecting operation.

BUT R2 must be very small so as not to disturb the setup. In general 1 Ω is sufficient, but here R2 is not at all negligible either in comparison to R1 (R2 represents 5% of R1), or in comparison to the resistance of the coils.  So either we take R2 smaller for example 0.1 Ω, or we measure as I indicated, R2 is then considered as part of the device and not just part of the measurement process, and we also take into account the power dissipated there.  Pout = CH3²/R1 + CH2²/R2.

If we keep the initial measurement process, then we can expect a 5% error on the measurement, which perfectly explains the COP of 1.061 measured by Itsu.
However, this does not explain at all the COP of nearly 3 measured by TK, which was well over 5%. If TK applied my correction, it shouldn't change much the result. So there is an error elsewhere in the TK measurement, or it is OU.

F6FLT

This still will not work if the FG and scope the guys are using share a common ground--which i believe they do.

You no longer have an isolated transformer,and will not obtain accurate power measurements the way you have depicted,as R2s voltage will not represent the true value of current flow,due to one end being coupled to the primary of the isolation transformer,and the other end coupled to !what is! the ground of the secondary of the isolation transformer.

Please see below diagram with FG and scope common ground added.


Brad

[ayeaye]

I don't see the scope doing anything wrong at 9 MHz, the waveforms are as they should for power to be negative. And when the power is negative, then indeed the coil generates power. This is nothing extraordinary, coil always generates power at back-emf, and the power trace has a negative part. Only in that case almost all of it is negative.

Can someone replicate? Itsu?

When the power is like 90% negative at 9 MHz, then it sure becomes negative at much lower frequency. The scopes should be well capable of it.

This last circuit proposed by Tinman, on the figure below, is the best i think, because it is the simplest, and easiest to measure. Thus the least measuring errors.

Maybe can be tried with different bifilar coils, coaxial? Not sure, these bifilar pancake coils made of thin magnet wire between cd-s or what, seem to work the best

[F6FLT]

F6FLT

This still will not work if the FG and scope the guys are using share a common ground--which i believe they do.

You no longer have an isolated transformer,and will not obtain accurate power measurements the way you have depicted,as R2s voltage will not represent the true value of current flow,due to one end being coupled to the primary of the isolation transformer,and the other end coupled to !what is! the ground of the secondary of the isolation transformer.

Please see below diagram with FG and scope common ground added.


Brad

I agree with you Brad. There is a ground problem if the scope and FG are not floating and share a common ground, which is likely.

Another problem is the  transformer itself. If it is made with two wires wound together, there is a strong capacitive coupling and the so-called "isolation transformer" is in fact a near all-pass circuit.
Even if it is made of two well separated coils, for instance coils diametrically separated on opposite sides of a tore core, the primary/secondary capacity is still on the order of pF to tens of pF, which is too much at Mhz frequencies.

Moreover the transformer adds possible concerns, for example making the FG appearing with a complex impedance.

I therefore propose the following simplified version, see picture.

No isolation transformer.
Only one ground.
The output power is easy and direct to obtain.
The input power is a little more difficult because the input current measurement is now made on the hot side of the coil. Nevertheless, I think there will be far less experimental bias than before.

If a COP>1 is always obtained, then it becomes very interesting. I hope Parzman and Itsu will try again with this new configuration.