Joule Thief

[SkyWatcher123]

Hi folks, I'm finally able to access this website again, was not able to for a week. Well I checked back in the archives of this thread and found the information jeanna referred me to, it is on page #732. Here is quote from jeanna.

Hi everybody,
I unwound the tor-61 which I was using for today's tests. This is  1 1/2 inch OD  if that.
I wound it 4T,7T,74T and saw that I had over 600 volts at 20khz or so. This is great, because the frequency makes it quiet!!
It easily lit a neon and I stuck on the 10w cfl
Half of it lit.
Next, I lit the 7w tube. It was easy to light.
So, encouraged, I pulled out the 20w tube.
This is interesting, because it lit about 1/3 the tube, but it lit it all at the one end. I could let go, no problem, but it would not expand to fill the whole tube.
This is where some heat could probably help, but this is cold electricity and it must do it without heat.
I include 2 pix.
1- is the 7watt tube. Notice how close to the ends it fills the tube with light. (>600v)
2- is the 1/3 lit 20watt tube.
@Bill, way to go!
Isn't this sooo much fun?
jeanna

I cannot get my 1" diameter toroid to light a fuoro, though maybe it is too small, since jeanna was using a 1 1/2" toroid. I used 26 gauge secondary pickup about 70 turn and used 24 gauge 4 turn base and 7 turn collector and tried 25, 50, 100 and 150 ohm base resistance. Though my DMM set on 750vac shows that it is exceeding 750 volts because it is going off the scale, yet it still is not lighting any fluoro and I have some smaller fluoros, small tubes, small cf's that should light up. My only guess right now is that the core just is not big enough, or does not have the right characteristics. Any help appreciated. Of course my intention is too power leds, though would like to get a fluoro going. Thanks.
peace love light
Tyson

[SkyWatcher123]

Oh and I tried an pnp tip42 and tip42c.

[jeanna]

Hi folks, I'm finally able to access this website again, was not able to for a week. Well I checked back in the archives of this thread and found the information jeanna referred me to, it is on page #732. Here is quote from jeanna.I cannot get my 1" diameter toroid to light a fuoro, though maybe it is too small, since jeanna was using a 1 1/2" toroid. I used 26 gauge secondary pickup about 70 turn and used 24 gauge 4 turn base and 7 turn collector and tried 25, 50, 100 and 150 ohm base resistance. Though my DMM set on 750vac shows that it is exceeding 750 volts because it is going off the scale, yet it still is not lighting any fluoro and I have some smaller fluoros, small tubes, small cf's that should light up. My only guess right now is that the core just is not big enough, or does not have the right characteristics. Any help appreciated. Of course my intention is to power leds, though would like to get a fluoro going. Thanks.
peace love light
Tyson

Hi Tyson,
I remember that I had to use a pair of 47uF caps in parallel with the battery to run the sketchy jt circuits.
I suggest this.
I also remember hazens used a cap ?? 100uF?? across the secondary leads.
I didn't find that a help, except one time when I had barely 425volts.

So, if you have not tried a capacitor, give that a try.
If you actually do have 450v, then you are very close.
Try adding a magnet to the connectors at the light.
Sometimes, I put a magnet at one or the other light end, then touch the light slowly down the bulb, then when it goes on it stays on, and I can even remove the magnets, once it is on.

The potentiometer might be a necessity.
Gadgetmall said it was. I have been able to use a straight resistor, but usually the tuning is so exact, the pot is better.

How s this circuit with a 20-28 led bulb meant for a 110v mains line? I bet it is great, and a lot brighter than the fluoro tube.

sorry for the silence. I have been busy away from my computer,

jeanna

[resonanceman]

Hi folks, I'm finally able to access this website again, was not able to for a week. Well I checked back in the archives of this thread and found the information jeanna referred me to, it is on page #732. Here is quote from jeanna.I cannot get my 1" diameter toroid to light a fuoro, though maybe it is too small, since jeanna was using a 1 1/2" toroid. I used 26 gauge secondary pickup about 70 turn and used 24 gauge 4 turn base and 7 turn collector and tried 25, 50, 100 and 150 ohm base resistance. Though my DMM set on 750vac shows that it is exceeding 750 volts because it is going off the scale, yet it still is not lighting any fluoro and I have some smaller fluoros, small tubes, small cf's that should light up. My only guess right now is that the core just is not big enough, or does not have the right characteristics. Any help appreciated. Of course my intention is too power leds, though would like to get a fluoro going. Thanks.
peace love light
Tyson

Tyson

I am not  sure that it is possible  to light a CFL with a one inch toroid.
You  have more than enough voltage. 
I would  suggest tuning your toroid to a lower voltage....... around 450V
More primary windings may be a way to get there?

Did  you try tuning  the primary to the toroid when  you first started?
If not .......try  putting a few wraps on  a toroid  for a secondary ........then put on your primary  with more turns then required.......then take  off  your primary winds  one at a time while  checking for voltage across  your secondary.....
Once  you  have  the best combination of turns  on your   primary you can take off the  test secondary and put on a bigger  secondary to get higher voltage.

gary

[SkyWatcher123]

Hi folks, Hi resonanceman, thank you for that information. Hi jeanna, thank you for your reply as well.

How s this circuit with a 20-28 led bulb meant for a 110v mains line? I bet it is great, and a lot brighter than the fluoro tube.

oh yes, it is surely adequate for my 20 led string, though I wanted to try and go a little brighter, so I took off the 26 gauge and put 120 turns of 24 gauge on it for pickup and it works even better, though the main reason is, I have no more 26 gauge on hand. Also I have to remove the 3 resistors in this string like I did the previous one and it will probably be as bright as plugged in the wall. it has 3-540ohm resistors in the string and i cant see any diodes that are obvious. Thanks, though i gave up on the fluoro with this small toroid, sounds too finicky anyway.
peace love light
Tyson