Joule Thief

[Pirate88179]

General Jim:

This is a question better answered by either Gadgetmall or MK1.  I have watched their work and came to the conclusion that if you change wire size, as in smaller diameter, then you need less resistance because the smaller wire has more than larger wire.  The core material changes the equation as well.  At first, I thought we needed ferrite but MK1 used powdered iron and said he got better results with it. (I believe your green toroids are powdered iron)  Same with changing the transistors....a different one of different value will require more/less resistance in the circuit.  Now, you know I never claim to be an expert on any of this stuff but I have been paying attention and this is what I believe to be correct.  These guys here can give you a more exact response but I think it is clear that the variable resistor, or resistors, is the key to being able to adjust for the other factors in the circuit.

Also, you really should not post a picture of my ex-wife like that.  She might get upset and get mad. Ha ha!!!

Bill

[timmy1729]

The backwards one will work off the emitter of the 2n2222 it will allso work off the base.
Going off the emitter is 6v going off the base is 9v.
This is off a 1.5v AA.

For the positive there both going back to negative source.

Then you can pick up the positive back emf off the collector of the 2n3055

@Slayer
Can you post a drawing of what you are talking about for the less experienced among us, such as myself 
I have got to try this BEMF stuff.

[timmy1729]

http://www.youtube.com/watch?v=XLNItTf9NrM&feature=channel_page

@ All:

Have a look at the above video.  This fellow says that we can double the amount of back emf by using a few tricks.  This may well apply to our research here.  Check out his other videos as well because he explains how this works.  See what you think and let me know.  Thanks.  http://www.youtube.com/watch?v=zP4dfxXhxxg&feature=channel  This video, he charges 4 batteries with only 2 batteries.

Bill

That was cool!

I have taken what I thought were a bunch of transformers off of a PC power supply and tried to replicate this first video. Well, I attached my meter to the other side. Anyway, no matter where I connected the battery or meter, I couldn't get any kind of reading. These are small transformers too. I thought those would work on a AA battery. Here are the pics of the power supply boards again.Are these big yellow squares transformers? What about the big green one? The green one has 4 pins on one side and 3 pins on the other side. They are equally spaced and I could not find any kind of transformer drawing with the 4 to 3 like that where the 3 were equally spaced. I haven't tried the BIG yellow one yet. But, even then, I don't know how to hook them up properly. I want to try the BEMF from that first video! That was just too cool!

[slayer007]

@Slayer
Can you post a drawing of what you are talking about for the less experienced among us, such as myself 
I have got to try this BEMF stuff.

Here's a drawing Xee2 redrew I penciled in a few spots where your can pick up BEMF.

The negative BEMF you can eather go back to negative or positive of the source battery for the BEMF positive.

For the positive BEMF you can do the same I like to go back to negative of the source battery.

This can allso be done with rectifiers instead of diodes.
I think with rectifiers you even get better results.

[Koen1]

@Timmy: yes, those yellow things and the green one too are transformers.
Not sure how you hooked up your meter there, but if you fed a steady DC
into them it may well be that you didn't measure much on the output side,
as typically induction in trafos happens when the current builds or drops
and when the magnetic field builds up or collapses, but not really when a
steady current maintains a magnetic field. Generally trafos work with pulses
or alternating currents. I may be telling you stuff you already know and if so
then forget about what I said just now, I'm not trying to act smart, I'm just
trying to think along with you there on why you didn't get a reading on the secondary.

By the way, I see a couple of really nice looking ring cores there too,
should be usefull in winding your own JT coils if you're going for that

@slayer: thanks for pointing out that suggested bemf connection.
So, if I'm folowing you, you're just saying connect the positive bemf feed to either the circuit positive or the battery negative,
and connect the negative bemf feed to either the circuit negative or the battery positive
And again, not to be a smartass, but doesn't a rectifier consist of diodes?

regards,
Koen