25mV Joule Thief powered by peltier merely using our body heat -Free energy 24/7

[gyulasun]

Hi magpwr,

Your idea on the copper tube and toroid cores around it reminded me of mainly Russian youtube videos where such transformer assembly was shown BUT there were a multiturn coil around the outer surface of the toroidal cores (because it has a normal cylindrical surface, such as Conrad shows above in his photo too). 
So I think the 100 turn may go onto the outer surface of the toroidal cores put close to each other, the 4 or 5 turn feedback coil would come on top of the 100 turns and the output may come from the thick piece of wire put through the copper tube as shown in this video:
http://www.youtube.com/watch?v=eH2TWPJiwEA 

I hope you understand how I mean the 100 turn coil, and I do not mean any extra output from such a transformer could be gained, I just trying to show a variant with the copper tube + toroid core type transformer.  By the way no any extra output is suggested from such "magic" transformer on the Russian sites as far I know.

rgds, Gyula

PS Here is a short video where a coil is shown as wound onto the outside cylindrical surface of a longer toroidal core, see from 0:17 to 0:23 :  http://www.youtube.com/watch?v=2qtVR1LkLSc

[magpwr]

Hi gyulasum and conradelektro,

From the russian demo by looking dates of posting youtube.It looks like original design came from Russia.
But video was not easy to understand,but some in youtubers managed to figured how it works and showed a better demo which is easy to replicate.

I'ts very interesting seeing a bulb lighting from a drill bit or copper pipe or screwdriver version from youtube user "Larskro".
Knowing all this metal got very very low resistance.How did bulb light from a straight metal still pretty much puzzles me with such a low current.

Since i was using the "Larskro's approach" and observed the "double amazing joule thief" video from a other youtubers.
I understand oscillator is needed to "resonate" the copper pipe(very low resistance,low voltage would definately be measured across pipes).Unfortunately i have not got the time to head down to hardware store to get myself copper pipe which toroids could be fittted.

Once i got copper pipe i will start with scaled up version(1.5V) then scale down from there to <100mV .Then figure out if need to stepped voltage from copper wire inside pipe since i believe the output is likely not rectified or DC output.

To conradelektro,
Please try higher voltage first 1.5v.Please take note the if your running something inside pipe may need to "insulate straight wire inside,unless it's insulated 14 or 18AWG copper wire" to prevent it from touching the inner walls of pipe like shown in double amazing video.

[conradelektro]

To conradelektro,
Please try higher voltage first 1.5v.Please take note the if your running something inside pipe may need to "insulate straight wire inside,unless it's insulated 14 or 18AWG copper wire" to prevent it from touching the inner walls of pipe like shown in double amazing video.

@magpwr: I tried the insulated wire through the copper pipe and Voltages up to 1.5 Volt.

@gyulasum: these strange transformers with toroids over a copper pipe are an interesting thing to explore, but I think they are not suitable for very low Voltage and low power. In the videos which magpwr cites there seem to be quite high currents (several hundred mA) flowing through the circuit. That is why the presenters in the Videos change the 1.5 Volt battery or 1.2 Volt rechargeable battery to have a fresh one.

Transistors ALD110800 and ALD110900:

With an ordinary Joule Thief circuit (bifilar windings over a toroid) I get oscillations down to 0,1 Volt and 10 µA. This is the lowest supply power I have ever seen in a JT (selfstarting). But I can not do much with these oscillations, wherever I place the LED, it will not glow. I will play a bit more with the ALD110800 and ALD110900 transistors.

It seems the ALD110800 and ALD110900 transistors need a connection to the negative rail (pin V-), then they behave well. The very low power consumption seems to stem from the "Drain Source On Resistance" of 500 Ohm. This opens interesting possibilities (one has great freedom with the coil at the Drain without causing too much current through Drain / Source) but also limitations. One also does not need any resistor at the Gate. May be that is bad for making LEDs glow, but for building a very low Voltage and very low power oscillator, this helps a lot.

Greetings, Conrad

[conradelektro]

Some success with the ALD110900 transistor in a Slayer Exciter type circuit:

The ALD110900 just wants to oscillate, no matter how badly matched the coils are.

Look at http://www.youtube.com/user/GBluer ,  GBluer shows in his videos many different Slayer Exciter type circuits and many different coils. I used the toroid I had from the 2SK170 experiments ( 4:100 coils) which is a very bad choice, and still it works fairly well.

See the attached circuit (hardly any components) and the photos. I will wind a tuneable coil (with a Ferrite rod that slides in and out), which should be more suitable for this type of circuit. The toroid dampens the oscillations down to about 100 KHz (due to its high inductance), a Slayer Exciter wants MHz.

The 2SK170 is still better for low Voltage (LED glows at 50 mV), but the 200 mV and 200µA I achieve with the ALD110900 are pretty good (given that it needs no additional components besides the coils, because the 100 µF capacitor is optional).

The ALD110900 pin V- is connected to the negative rail. Note the internal diode from the Gate to the negative rail. In a Slayer Exciter there always has to be "something" (diode, capacitor, inductance) between Gate and negative rail.

Greetings, Conrad

[gyulasun]

Hi Conrad,


Data sheet for your ALD MOSFETs says:

"For most applications, connect the V+ pin to the most positive voltage and the V- pins to the most negative voltage in the
system. All other pins must have voltages within these voltage limits at all times."   

I know you mentioned you connected V- pin to the Source which is at the most negative voltage in your schematic and maybe it would be good to connect V+ pin to the positive pole of the supply voltage. Of course this latter is valid for quad device ALD110800 (its V+  is Pin 13) and there is no such V+  pin for the ALD110900.
One more thing: you surely noticed the pins with asterisk symbol as (IC*) and these pins are also recommended to connect to V-  i.e. to the most negative voltage rail.  Such pins for the quad device ALD110800 are Pin 1, 8, 9 and 16 and for the dual device ALD110900 these are Pin 1 and 8.

You mentioned the Drain Source On resistance is 500 Ohm, however this is valid whenever the Gate Source voltage is +4V (at Vds=0.1V). And how well this condition is fulfilled in your shown oscillator circuit, an oscilloscope could be used to see the Gate source AC voltage waves with respect to the Source pin as being the most negative point.
OF course if you connect the dual device in parallel, then you would have about 250 Ohm RdsON and for the quad device this would be about 125 Ohm.

You also mentioned the internal diode between the Gate and the V- pins and it occured to me that while current can only circulate via this internal diode and via the 100 turns coil and via the LED when the induced AC voltage polarity across the 100 turn coil corresponds to the forward direction of both the LED and the internal diode (this is why the LED direction is important) so IN CASE the internal diode is a normal Si diode (albeit a very fast one) the forward voltage drop across it may be at least 0.6V and this lowers the useful voltage that may feed the LED from the total induced AC voltage peak so I wonder if connecting a Germanium or Schottky diode across the Gate Source pins in parallel with the internal diode (anode to anode and cathode to cathode) you may be able to gain some more brightness from the LED. Maybe this extra diode influences oscillation too much and you get just a dimmer LED, well I hope not... and if you agree and feel like testing it, please do. Even another Si diode like 1N914 or 1N4148 might be worth trying if you do not have any Germanium or Schottky diode at hand.

You have very nice results!

rgds,  Gyula