Lasersaber strikes again. A joule thief king ?

[totoalas]

http://www.instructables.com/id/Electricity-Generating-Footwear/step12/Installing-The-Insole/
Another way to charge the caps using piezo electric disc .. can integrate   this as well
totoalas

[d3x0r]

edit: oh yes, anyone know if the 200 turn collector coil is wound as the first or second coil, thanks.

I would guess from prior schematics and habits that the primary is the inner winding...

[SkyWatcher123]

Hi folks, Hi d3x0r, thanks for the information, i kinda figured that.
Though i wired one with 200 turn as first coil 30 awg. and outer coil 100 turns 30 awg.
Got lasers v3 to work, charged a 10 volt 3300uf electrolytic cap and it lights led for about 10 seconds and sometimes sputters back lighted again. 2n3906 pnp transistor was used.
Though i may have used to small of an e-core.
I get the feeling one needs the core he is using to see similar results.

So after that, today i decided i wanted another non-modified led bulb lamp that was a bit brighter than the child's led bulb lamp i built.
Well i got it brighter with another ferrite flyback core, using joule thief style wiring with secondary coil.
Though it was a little less efficient than the child's lamp, so i decided to wire it joule ringer style and it was much brighter and higher frequency.
Thing is, the efficiency dropped to around 105 lumens per watt for a 75 lumens per watt rated bulb.
Then i put in the older version of this 6 watt ecosmart led bulb and it was less bright, but the efficiency went very high, to around 167 lumens per watt at 1.22 watt input.
Again same bulb, just a previous version, that must have different circuitry inside and it is built differently, the newer one seems much cheaper built, though solidly built.
This joule ringer is giving 2.2 times more lumens per watt from this bulb, compared to wall powered.
Granted it's only giving 207 lumens at that efficiency, though again, i can imagine what that g7 filament led bulb would do at its stock 138 lumens per watt and not to mention that bulbs power factor is around .5 or so, so even more room for better efficiency.
I watched that video by OUbrads and it just proves how we can get very usable light for little input.
Let me crunch some numbers here.
If we used that g7 vintage led bulb rated at 138 lumens per watt and used an efficient ferrite flyback or equivalent core, maybe even like laser is using now and since i'm getting 2.2 times more lumens per watt than stock rating, we may be able to get 303 lumens per watt with this type of setup.
I do observe that these high lumen per watt results, only seem to occur at lower brightness levels.
Though that is not a problem really, because if using the one bulb is not providing the needed light output, then we just use 2 or 3 to do the job, while maintaining the same high lumen per watt setup.
I have a gutted 6 watt cree led bulb here and i will test to see how well it runs with this joule ringer setup and i will probably gutt one of these newer 6 watt ecosmart bulbs to see if it can run more efficiently, though it doesn't look like it was meant to be taken apart. (el cheapo)
peace love light

[d3x0r]

Hi folks, Hi d3x0r, thanks for the information, i kinda figured that.
Though i wired one with 200 turn as first coil 30 awg. and outer coil 100 turns 30 awg.

can't really confirm if higher inductance is better or not; but the litz wire is like 50 strands of 30awg in parallel which would have much less resistance....  my 32 guage coil barely works

[conradelektro]

2n3906 pnp transistor was used.

Though i may have used to small of an e-core.
I get the feeling one needs the core he is using to see similar results.

My experiments with LaserSabers very low power circuit show without any doubt, that the transistor is the most crucial element.

My best result was with a MPS18 transistor (which I bought from MOUSER http://at.mouser.com/Search/Refine.aspx?Keyword=MPSA18, but you also find them on ebay). All other transistors I tested cause a power draw which is at least 10 times higher.

Look at my post http://www.overunity.com/14591/lasersaber-strikes-again-a-joule-thief-king/msg405416/#msg405416

The MPSA18 transistor (in this circuit) has a very short "on time" of about 600 nano seconds, much shorter than with any other transistor I tried.

The type of core, the wire and the exact number of turns of the two windings (ratio primary/secondary) have much less influence on the result. The right coil can still improve the result, but not by more than by a factor of two or three.

The brightness of the LED depends much on the LED type.

So, get some MPSA18 transistors and you are in the game (in case you are interested). There might be other transistors with a similar behaviour, but one has yet to find them.

I also suspect that the MPSA18 transistor allows some current feedback to the power source (electrolytic cap). Negative current from the secondary leaks from the base into the emitter and draws the primary below ground which then causes a higher "back EMF" which feeds current back into the cap. But this is just a wild theory to explain the 10 fold power requirement drop with a MPSA18. My expertise is not good enough to clarify that.

Greetings, Conrad