Joule Thief

[xee2]

@ sm0ky2

Your 2 in series JT may be generating enough voltage to light a neon bulb (about 120 volts). There is no need for the rectifiers, just put the neon across the leads of the last secondary coil.

[jeanna]

i made the rectifier out of LEDs,connected to the secondary of the first JT.
using the output to operate the second JT, which had many many turns on its secondary

I will have to try that.
I like the idea of using the lights as rectifying agents. very efficient.

cap charges to 60v after about 12 seconds.
removed the cap and shorted across it and got large sparks.

How much in 4 seconds? or 2 seconds?

as far as i can tell the current drawing from the battery ...

strange things we're doing with a single cell battery thats near death...

Yes,

The secondary is where the action is on these.
I mean there are people who think a joule thief is to drain a battery really down. but it is much more than that.

The secondary of one of the joule thiefs is enough to give you 60 volts easily without a daisy chain. Some people light neons with just one and that is over 100v way over, because it seems you need more volts when they are spikes like this, but still they are easy to get once you get the hang of it.

And yes, the battery is not being used for much more than to turn on and off the transistor. It is a remarkable little circuit.
This is really cool what you did. I will see about it tomorrow.

I think.

My son's fiancee just told him she wants to get married this summer instead of in 2 years,

and it might be next week. 
I may be too busy for a couple of weeks.

jeanna

[resonanceman]

I threw together a JT with components I already had. It turned on the first time   

2n3055
3 super bright clear deep red LEDs 2.5V Max, 25mA Max 110mW Max 3500mcd
3 super bright clear amber LEDs 2.4V Max, 25mA Max 100mW Max 5500mcd
5K ohm pot - I need to get a 1k for finer tuning.
6" x 1/2" diameter ferrite rod with 110 bifilar wound 22awg magnetic insulated wire

The 6 LEDs "look" the brightest at about 220mA @ 1.17volts.

When the POT is turned to extreme settings, left then right, the measurements are:
left: 47mA @ 1.27volts
right: 748mA @ .835volts.


How do these results fit in with what you all are finding?

Thank you,
DonL

Don

Sounds  good

You might be able to  get the  current  a little lower   if  add a cap across  the  pot to make a tank

The  tank  resonates  ......the  output  goes up and the current draw  goes down


gary

[dllabarre]

My son's fiancee just told him she wants to get married this summer instead of in 2 years,
and it might be next week. 
I may be too busy for a couple of weeks.
jeanna

Kids... gotta love'em.
I have 6 myself and not a week goes by that at least one of them surprises me with something. 

DonL

[dllabarre]

You might be able to  get the  current  a little lower   if  add a cap across  the  pot to make a tank
The  tank  resonates  ......the  output  goes up and the current draw  goes down

gary

Good idea... I'm familiar with a Tank circuit and it's behavior.
I'll try that next.

Thanks,
DonL