Itsu posted this 2 weeks ago - Last edited 2 weeks ago
Thanks for showing Vidura,
So you use the Push Pull (yoke / toroid) around 18KhZ to drive the Grenade coil and series capacitors into series resonance.
Normally this series LC consists of the Inductor coil (around the lower part of the Grenade) and the series capacitors, but this is to show the relation between resonance signal and (inverted) modulation signal if i understand correctly.
Itsu
Vidura posted this 2 weeks ago
@Itsu
The images shows the relationship between the main resonator and the modulation signal, in this case for parametric excitation. Anyway for the layout with a grenade coil the signal should be extended to half of the period for better performance, as it is a circuit with lumped parameters, a travelling wave resonator.
If we consider the physical processes taking place in the BTG, being the same as in the kapagen and the eternal flashlight, then it becomes clear that various layouts and combination of components are possible. I am very confident, that the only reason for such few replications are due to the lack of understanding this underlying principles. There are millions of skilled and smart people all over the planet, but without knowing what we have to look for, the chances to get this working are like a lucky strike in the lottery.
So we have a source of high energy scalar waves or pulses as one component, then we have the main resonator, which has a resonant frequency by orders lower (mostly!). In this main resonator the process of "energy pumping" takes place, or better a transformation from one form of energy into another form more convenient for us. It is something like a heat pump, but of course with other manifestations of energy.
Then there is another part, which has the function of dissipating a form of energy at a different level. If you familiarize yourself with the thermoacoustic machines, you can see the similitude, there has to be a gradient of temperature, hot on one part, and cold on another, and the oscillations will start by itself. In most BTG devices this is the grounding wire, which is usually quite long. At small energy levels it could be the chassis or enclosure of some components as well. Then there is usually another part, which is used for removal of the output power. It is not mandatory, but the process of removal has to be controlled some way, otherwise it could stop the main resonator. If we have a constant load, it could be linked directly to the main resonator, which will be in LCR resonance in this case, but it might be more unstable.
The main resonator can also be driven by a separate coil in LC series resonance and the push pull for example, as you have stated above, but the process remains the same.
Itsu posted this 2 weeks ago
Hi Vidura,
Great info, so it’s the "main resonator" (Grenade) which needs to be in resonance too to produce the "energy pumping" process.
Many diagrams out there show not really that this Grenade is put into resonance, but instead the Inductor is put into series LC resonance to drive the Grenade.
I have tried to get both the Inductor and Grenade (closely coupled) into resonance, but this fails as they get over couple
d and reject their resonance peaks.
So, the Grenade is most important to get into LCR resonance and then have the correct circuitry for removal of the output power from the Grenade.
Thanks so far,
Itsu
Vidura posted this 1 weeks ago
Hi all, the last time I was working on the improvement of the Kacher-Brovin driver. It took many hours on the bench, something tricky the circuit. Four drivers and three MOSFET get fried on the way, but finally it came out well. Below short video:
https://youtu.be/2VFn6VtlVTkNext I will add the push-pull and main resonator, I thought to test some different options of coils and layout, as far as resources allow.
Vidura
Itsu posted this 1 weeks ago
Vidura,
looking very nice, the driver looks very efficient now with only about 9.6W input.
Also the modulation of about 10kHz comes in the direcrion of what is needed (15-25kHz).
Would be great to see the modulation pulse train on the scope together with the Kacher output one time.
Looking forward to your next steps.
Itsu
Vidura posted this 6 days ago
Here is a new coil for the Kacher-Brovin resonator; the reduced diameter allowed to increase the resonant
As the number of turns is +500 the emitted scalar waves are strong enough.
With the antenna attached, the resonant frequency is 1.8 MHz.
Below you can see the comparison with the modulation signal, which is still provided by the FG.
Here with a modulation of 18khz@50%
It can be noted that the start-up of the circuit is very fast, of course the decaying of the dampened wave after the shutdown is present.
There is some ringing because the scope is not grounded.
Due to the high ambient temperatures, we have 40ªC these days, I found that the driver becomes very hot, so for a reliable operation this needs to be improved further.