Joule Thief

[Pirate88179]

@ Pirate88179 and Freezer

Magnet causes bright spot on tube because it pulls the stream of ions from the center of tube causing more of them to hit the phosphorus coating on the tube (more ions = more light). Transformer sound may not be getting quieter, it may be getting higher in frequency (going above audible). Higher frequency is good if that is what is happening, because more energy will go through a given capacitance value at higher frequencies. Thus it is easier to light tube with only one wire at higher frequencies. To see if C or D cell will harm circuit, check the current draw when using AA battery and D battery. If current for D battery is not significantly higher than AA battery  then D batteries are safe to use and will last longer.

Excellent point on the higher frequency that I am unable to hear.  I am leaning toward that as what is taking place. (now that you pointed it out)  I did not notice a bright spot near my magnet on the lit tube.  On the second tube, it altered something inside the tube to allow me to "drag" the light the full length of the tube to have it light also.  I like your explanation though, it makes sense, the more ions that strike the coating on the tube, the more light.

I still wonder why my hand would not do the same thing?  Maybe I was grounded too much?  Not enough?  Very dry inside my place and a lot of static builds up when you walk on the carpet which may affect it one way or the other.

Question:  How do I check the current draw of this circuit without frying the fuse in my meter?  Is it safe to check coming out of the battery?

Bill

[WilbyInebriated]

@ Wilby:

Nice circuit.  Hopefully, I will give that a try.  Then it would be easy to make our own led bulbs, or run these tubes from the wall power.

you can run multiple led's from ac with a resistor and a cap. you can also use it to regulate mains voltage pretty well for a 5v supply with a zener. i take apart my old incandescent bulbs that are burnt and put 2-4 white led's in them along with the cap and resistor. it all fits pretty nice and works well.
see this page for more details.

[WilbyInebriated]

Have a great Christmas.  I still got to pick up some more presents, and am not looking forward to weaving through the crazy mobs.  Today it took 20 minutes to find a parking space. :/  When I was leaving an old couple was patiently waiting to take my spot, and in swoops this jerk and takes the spot from them..I should went back and said something, but I didn't feel like getting into a confrontation over a parking space. 

the mobs... seriously, take one of your circuits with you in some discreet hand held package like a tic-tac box. it makes a great 'cattle prod'. also, the 330volt caps make nice tazer projectiles when they are fully charged. they fly nicely with a tube of paper attached to end opposite the leads. would be perfect for those swoopers.

[innovation_station]

well!!

there better uses.....  hummm 

anyhow...

i made you guys a vid of my flashlight modded

ist!

http://www.youtube.com/watch?v=ml5-tviRPCQ

[xee2]

@ Pirate88179

Good question about meter. They usually say on front what max current they can take. Always start with meter on highest scale and work down. I was not suggesting putting the meter across the battery. I meant to put the meter in series with the battery while the battery is powering the circuit. My AAA is running at about 360 ma. So you should use a meter able to read at least one amp to be safe, but I suspect that the current will not be much higher with a D cell than with AAA battery. Try measuring your AA battery first.

EDIT: I could not find a D cell, but I did find an old flashlight with C cells. The C cell was running at about 440 ma driving the Fuji board.