Joule Thief

[FreeEnergy]

so what i am getting is that you can use a core-less toroid? just use the coil itself?

[xee2]

so what i am getting is that you can use a core-less toroid? just use the coil itself?

Cores are not needed. But the permeability of the core reduces the number of turns required for a given inductance. The higher the permeability is the fewer the turns that will be needed.

[jeanna]

.... RadioShack TIP3055 NPN Transistor:
The transistor works fine, but its NOT a TIP3055... its a MJE3055, which is rated at 75W not 90W.Was ...


I ended up ordering 10 from Digikey as they were cheaper and, hopefully, TIP3055's.

Bill

Thank Bill.

I looked them both up and there is a dizzying amount of information because so many different manufacturers make these.
I am glad the mje called tip3055 from rs worked so well.
I am also glad the tip31 from allelectrronics  worked well.
I guess I had better try the rs version of the tip31 today along with both others to make a personal comparison.

The good news is that so far they are all lighting the cfl.

And, from my experience, the little 10w cfl which I found at wallmart in a 3 pack behaved like lidmotor's jeanna's light.
I could get the rheostat to turn it way down with much more movement in the knob than the 20 watt, so I could be more precise, and I liked that part.

Now, each one of those cflights comes with 2 transistors.
They are different too.
I am not sure what they are doing, but the 10 watt has a little plastic half round in 2 places, and the 20w has one with the built-in heat sink.
These might be useless to us since the design assumes a starting voltage of 110v sinusoidal, but someone who loves to sort through the junk piles might be able to help tell us if these components are useful here.

(Oh, and... MS paint won't light your table... )

jeanna

edit add

so what i am getting is that you can use a core-less toroid? just use the coil itself?

There is really only one way to know.

jeanna

edit add2
So xee2, is it this?
j
fixed per xee2

[gadgetmall]

Thank Bill.

I looked them both up and there is a dizzying amount of information because so many different manufacturers make these.
I am glad the mje called tip3055 from rs worked so well.
I am also glad the tip31 from allelectrronics  worked well.
I guess I had better try the rs version of the tip31 today along with both others to make a personal comparison.

The good news is that so far they are all lighting the cfl.

And, from my experience, the little 10w cfl which I found at wallmart in a 3 pack behaved like lidmotor's jeanna's light.
I could get the rheostat to turn it way down with much more movement in the knob than the 20 watt, so I could be more precise, and I liked that part.

Now, each one of those cflights comes with 2 transistors.
They are different too.
I am not sure what they are doing, but the 10 watt has a little plastic half round in 2 places, and the 20w has one with the built-in heat sink.
These might be useless to us since the design assumes a starting voltage of 110v sinusoidal, but someone who loves to sort through the junk piles might be able to help tell us if these components are useful here.

(Oh, and... MS paint won't light your table... )

jeanna

edit addThere is really only one way to know.

jeanna

edit add2
So xee2, is it this?
j

Hello Jeanna Are these marked COOL WHITE . or Daylight  > I assume cool white .
Al

[xee2]

so what i am getting is that you can use a core-less toroid? just use the coil itself?

See lidmotor utube video with tunable inductor. He starts with coreless coil.