Joule Thief

[jeanna]

@xee2

Just as a test, try holding your finger on the windings and see if that decreases the brightness of the LEDs. Your finger will increase the capacitive coupling between the windings. If this is the reason for the differences you are seeing, then by making the secondary winding a separate coil around the toroid instead of winding it over the top of the other windings should reduce this effect.

I cannot see any difference from touching the lights. I looked for it today directly, and also I didn't see it last night, (and with all the fiddling to make the different wires touch the array, I would certainly have noticed it somewhere.)

EDIT: It would be interesting to see if the LEDs are brighter when the two coils used for the basic JT are separated as Mk1 does than when the two coils are wrapped bifilar together as is normally done. The added capacitance between the base and collector will be less when the two coils are not close together (but the inductive coupling will be the same). I always use separated coils but I never actually did this test.

Checking for brightness is very difficult. A meter that detected brightness could do better than one's eyes.

II checked the rectified voltage with the same materials arranged
1- the way MK1 did it and
2- the little toroid style.

28v and 29.v rectified volts off that 52 turn secondary for the MK1
and
29v and 25v in 2 directions rectified volts off the secondary when made the other way.
I called it hybrid because it used the same number of turns of the same types and sizes of materials, but made the little toroid way.

Sorry for the confusion and edits, My notes confused me.
The 52 turns of the secondary gave the same rectified voltage on both

I had some extra length when I was making the hybrid, and so I tried making more turns and got a bunch more volts each way when rectified.

I will look, but it would need to be very different for me to see a difference, I think.

@MK1

@jeanna

Thanks !

you're welcome.

@jesus
PERFECT. VERY NICE PICTURE.

THANKS.

@Arctic Knight

Please look at page 177. Jesus just made a very nice drawing of the circuit.

thanks everybody,

jeanna

[jeanna]

MK1

What are the specs on your last one?

Last I heard you were having trouble replicating the first one.

Also, please tell us what went wrong? It will make it easier for us to skip some of the mistakes. (I usually have to make them all myself, anyway, but it might help us.)

Thank you.

[innovation_station]

@ mk1


im gonna have to dup your toroide i have a few bigger ones ... not too big tho i will find them then i will build your style unit ...

my 12vdc bulbs are like 60ma  as i recall now have not dug them out yet....

and here is a pic cap to cap test unit to mesure in vs out

caps are 35vdc 4700uf both

ist

well i just ran the test board ... and .... 

well tests indicate OVERUNITY....  i could be wrong tho .... but in a 1 shot kinda deal i put 2-3 vdc in the out cap ....

hummm

[xee2]

@ jeanna

Thanks for the test results. It would seem that you have shown that there is not much difference between winding the JT coils separately and winding them as bifilar. That seems like valuable information to know. I think it also shows that adding a little capacitance between coils does not seem to make much difference in performance. Therefore it seems that your experiments are indeed showing that the secondary wire diameter does make a difference in performance. Very interesting. Thanks for doing the tests.

[electricme]

@all
Cheesy Smilie missing from line up.

Has anyone beside myself  noticed the cheesy smilie is not there? I noticed this when at home using XP,
I am elseware right now using anothe PC, I installed Windows 7 BETA on it and I still got the same icon missing.

jim