Joule Thief

[Pirate88179]

Nice work. Ive tried to make the simplest joule thief for kicks with 3 different toroids I had laying around. Works with 3 volts but not 1.5.

What transistor were you using?  If you use the 2N3904 it should work very well on 1.5 volts and then down to about .3 volts or so.  If you use a germanium transistor, you can get it down even lower.  If you post a pic or two of your efforts, perhaps we can help you get it to work on a single AA.

Thank you,

Bill

[guruji]

Hi guys I've build the Jesus charger but it did not charge my AA battery. I used a 104 cap maybe this is not good. Near the first diode it was giving me about 1.77v but it went down on the two diodes.
Any help please?
Thanks

[ian middleton]

G'day all.

@ Bill,  nice work with the flashlight. Given there are various levels of "deadness" in your batteries how much longer do they last , on average?



Ian

[xee2]

@ kooler

If you try my biasing technique I recommend using a 10K resistor in series with the zener instead of the 1K as shown in my last diagram. It triggers fine and reduces the stress on the zener.

Unfortunately, my ignition coil is shorting inside and I do not think I will buy another one just to try this. So I am not sure what I will do next. I hope you will continue to post your results.

[IotaYodi]

This lights up fine with 3 volts. Maybe the toroid isn't ferrite. I tried a choke off a monitor cord but thats more cylindrical than toroid. Yes Im using the 2N3904.