Joule Thief

[resonanceman]

They couldn't have given this device a better name.

because i feel like a Stole something !!!!

Smoky

I remember the feeling   

Really  it is more like you  found something that was stolen  from  us .

This  kind of stuff should  be  taught  to   our kids  in school .......but  if you  ask  someone  that is " educated " in electronics   they  will tell you  what we are doing is impossible .



gary

[jeanna]

Wow,
What an active crowd today!

I just want to add a couple of pieces.

Xee2,
I am going to try again, but so far I have not been able to get the germanium to turn on the jt using the EB. That is the reason for my silence. I tried the parallel cap supercap like Bill's first red led last year, and still no.

After that failure I moved the probes and I am thankful for the reminder. I keep forgetting to go out to set this up during the day.

@All,
I have started to time the 4 inch fluoro tube. I am giving it 10 hours of leeway since xee2's lasted that long. I will report tonight when it is out.

@Gary,
I always wondered if part of Bill's immediate success was because he used that really fat wire along with the cap.
My new EB has speaker wire which is fairly thick too.

@DonL,
I agree with xee2,
You have come to the right place.
Please read the thread, because there is such a wealth here.
I have read the whole thread up to page ~350, 3 times. It is an easy and enjoyable read, and full of valuable information.

@Sm0ky2,
I had trouble with the 3055. I had 2 of them so it wasn't the transistor.
It turned out to be a combination of things for me.
The number of turns,
The resistance of the base resistor
There was a cap needed. I was not in the habit of using a cap to help get the system going. But it is with this set-up.

Now, thanks to the difficulty you had, there is one more thing i/we can add to our ways of making this work. - a pearl of wisdom.

@ist

i just put a 33 ohm resistor on the  pos side of the battery ... my out put went from 240vdc to 15v .......

Yes, in fact I am using a 33 ohm resistor right at that spot to keep from blinding myself with my ac from secondary experiments. It makes a very big difference!
I think this goes together with the fat wire thing.

Fat wires have much less resistance.
In playing with the sliders at barrys coilgun site, it quickly becomes clear that the frequency and volts out and the general success of a RLC is dependent on keeping the resistance low.
Good discovery. I am glad you shared it.

jeanna

[xee2]

@ jeanna

Xee2,
I am going to try again, but so far I have not been able to get the germanium to turn on the jt using the EB. That is the reason for my silence. I tried the parallel cap supercap like Bill's first red led last year, and still no.

What is the part number of the germanium transistor you are using. I will try to find a data sheet. If you have a data sheet can you post it? They have lower gain than silicon transistors and so you will need a lower base resistor value. I have not made one so I have only guesses. Maybe Gadgetmall can help you.

[resonanceman]

Smoky

Just  a little tip about   taking pictures .

I  assume  you are  using  a simple  digital  camera .....the  point and shoot kind .
Everything  should  be in focus .
The  reason  that  everything is out of focus  is called  camera shake .
When you push  the  button  you are also pushing the camera a little .....it causes the  camera  to pivot   as you take the picture .
A way around  this is to  place  your  finger on the button  and your   thumb  directly   opposite   your finger  on the other side of    the  camera and gently  "pinch " the  camera when you want to take a  picture .
When   you  pinch  the camera  the  forces     are  in line .......so no camera pivoting .......your  pictures   will come out much clearer .   




gary

[xee2]

The GDT sparkgaps work. But, they are not as good as a real spark gap. However, they are easy to use at low currents and voltages.