Self running coil?

[skywatcher]

Would you tell what is the DC voltage in the electrolytic cap?

Also, you use the 680 Ohm in parallel with the input i.e. parallel with gate-source, right?  What is the input square wave amplitude I wonder.

The DC voltage at the cap is 6.16 V. It's constant, as far as i can see with my multimeter.

The resistor is in series with the gate (to protect the generator against short circuit in case something goes wrong). The square wave voltage measured directly at the gate is 2.8 Vpp.

[gotoluc]

gotoluc

As you powered led with extra coil what stopped you from connecting led back to the gate of mosfet and closing loop then disconnecting function generator ?  Or using more pickup coils and power directly an oscillator chip driving mosfet ?

To everyone

One way to Isolate the signal generator is to use an OPTO Isolator and connect the switching side of the OPTO to the capacitor bank to feed the mosfet gate. I do have a 4N35 and a H11D1 which I both tried last night but they are way too slow to shut off. At 1KHz they were at 95% duty and to full on with frequencies over that. My signal generator is fixed at 50% duty. So these are not working or I don't know how to connect them correctly. If someone with electronic knowledge can recommend an Isolator which could work a up to 50KHz and still keep the 50% duty cycle using a component that I can pickup locally please look at the two suppliers in my city for stock: http://www.resetelectronics.com/VALUE/index.asp  or http://www.active123.com/

The other way is using the pickup coil to trigger the mosfet. This is complicated because the pickup coil is a sine wave that it peaks are out of phase with the mosfet pulses. So again I'm at a loss of how to use this energy or build a circuit that could create the very exact frequency, gate drive voltage and current that is needed.

I'll see if I can pickup a CMOS 555 locally and try to power it from the cap bank by keeping it in the 10vdc range.

AT EVERYONE If you know how to close the loop please provide a complete drawing of how to build it. Please do not just say do this and that. I am willing to do everything I can and I think I have done all I can with my minimal electronic knowledge I have.

Thank you for your time

[gotoluc]

with a small mirror glued on the magnets and laser pointer you can amplify the vibration effect if exist .

great work!

Good idea wings!

Thanks for sharing

Luc

[NextGen67]

Hi Luc,

<...>
Now I cannot tell you how much from this leaks through to the tank circuit, maybe others can help here too. Will think about it.

rgds, Gyula

Gyula,

Would it not be possible to simply attach only the signal generator to the mosfet and then connect the Cap to the source and drain, and just observe what goes into the cap ?

Actually a [known] voltage/amperage could be supplied to get it at the correct working point, but this can with a calculation be subtracted from the cap value later again?

EDIT: No need to attach battery I guess, since the signal generator can easily deliver enough voltage ?  Anyhow, after say 5 minutes of charge, one could see how much the cap collected.

--
NextGen67

[gyulasun]

Gyula,

Would it not be possible to simply attach only the signal generator to the mosfet and then connect the Cap to the source and drain, and just observe what goes into the cap ?

Actually a [known] voltage/amperage could be supplied to get it at the correct working point, but this can with a calculation be subtracted from the cap value later again?

EDIT: No need to attach battery I guess, since the signal generator can easily deliver enough voltage ?  Anyhow, after say 5 minutes of charge, one could see how much the cap collected.

--
NextGen67

Hi NextGen,

If you remove the toroidal coil, you cannot get resonance at all, hence there cannot be significant voltage developed in the cap if you test your suggested circuit.  This is what I think.

Luc already exactly maintains equlibrium between the output circuit losses and the input power from the generator, I am afraid, because you can see from his video the zero current is achievable in the 1 Ohm resistor between the electrolytic caps, this resistor just monitors the current taken out or pumped into the tank circuit.  Luc can get both positive and negative currents in the resistor, so just zero value shows equlibrium: loss=input (this is what I think).
Notice here that I did not mention the output power received in the pick up coil or later in coils, that would be already an extra gain.

Gyula