Joule Thief

[Pirate88179]

Jeanna:

Very well done.  I had another 2 cfls burn out in the last week or so which gives me plenty of parts to try this.

The toroids in the cfls I have seem to be the painted sintered iron ones, is this what you used?

Great presentation.  I have not yet figured out how to place photos in my videos yet.  That looked really good.

Bill

[jeanna]

I took it off.
The last pic which is a bright beauty got clipped off. It only flashes one frame.
I will redo it in the morning.

jeanna

[jadaro2600]

I noticed that loading the toroid on a tertiary causes effects, not sure how profound, but they are destructive on the derivative that I built.

I thought that, on a standard setup, with two driving coils and a large secondary, a small tertiary coil be incorporated.

The tertiary coil be three to four winds of copper, rather than attaching this to anything that creates light, it could have a varistor / potentiometer attached between it's leads which creates a shunting load - this may have the effect of an electrically isolated tuning apparatus.

This thought was inspired by IST's tuning coil mod, but it makes a simple effect and uses less equipment.

Not sure how useful this would be though, as the circuit goes into resonance as it already is, the idea would be tuning for both directions of the flux, as the potentiometer usually has three leads, an optimum could be set; using previous data - a diode on the middle lead, and have the other ends connected normally ..this would allow less resistance in one direction than in another and thus circulating pulses and magnetic fields could be experimented.

Red is the mod, green are the common coils to base and emitter, while blue is the secondary.

As is, the image is most basic in design, the idea would be to first find an optimum for each direction and incorporate additive or subtractive resistance as needed.

edits: had to sign it, been forgetting that lately. 

[crowclaw]

Here is a pic of those small toroid's found in CFL's this one is seen as removed and has three windings. What I have done is wired up as a JT without rewinding the coils. The yellow wind is left untouched. The scope screen PC shot shows the wave form, and the circuit was running at 1.5 volts  with a 10K adjusting pott. Frequency 158KHz. I just put this in for those new members who want to try the "Joule Thief" circuit out using scrap.

[crowclaw]

PC sope shot of small toriod