Joule Thief

[crowclaw]

Crowclaw's circuit:

Many thanks Bill.  Merv

[jeanna]

IMHO, chiliqueen's circuit is not a joule thief.
I do not see a bifilar (centertapped) primary on a toroid... or even without a toroid.

I always seem to be going in the opposite direction from the crowd.

While I am dreaming and working on downloading information about how this is done without a transistor, some others are adding transistors.

I did even buy a pnp to match the npn because suchayo asked me to replicate his design which I think is a lot like this one, but somehow, I just have other things to work on that seem more free.

@crowclaw in the beginning 100 pages of this thread there can be seen many circuits (both simple jt with secondary and gadget's fiji mod) that use 20mA or less and drive many leds.
The lamp at my bedside table has 24 leds and runs with that little amount of mA. It has run for over a month of normal use and I expect 6 months will be minimum before a recharge will be needed.

@All, So, why use a second transistor???

Why not expand on the principles that have been shown lately?
For instance,
xee2 had a filament bulb lighting from kooler's circuit.
This is real potential.

Why not follow up on this and take it to higher limits?


BTW
I am coming to the conclusion that switches cannot take the effects of the higher volts.
For the second time and second switch, I have seen that the unmodified led bulb, which keeps the High voltage oscillating after the switch is off, has drained a battery over night to the point of leaking.
It was a cheap chinese AAA so I tossed it and washed the battery holder, but this needs to be solved.
We need a better way to switch the battery on and off.
I think an extension of Bill's idea or some kind of physical removal of the battery wire with easy replacement in the dark is good to work on.

thank you,

jeanna

[kooler]

@All, So, why use a second transistor???

Why not expand on the principles that have been shown lately?
For instance,
xee2 had a filament bulb lighting from kooler's circuit.
This is real potential.

jeanna
the circuit xee2 and me ar working on does indeed light small bulbs
i'll make a video soon showing it.. it just to cold in my cellar to work right now..
the whole reason for me trying to light bulbs is to make heat with low ma draw

but till video day i have another circuit schematic here that i use in solar lites
it last 6-10 hours on a AAA battery... very much like a JT..lol

[Pirate88179]

Jeanna:

I may have misunderstood you earlier about your switch.  Are you trying to turn on and off your pick-up coil leads (HV)?  If so, no wonder you have problems with it.  If you do that, your JT is still "on" even though you have turned "off" the HV leads, and it will drain the battery.  Just get a decent toggle switch and cut your power on and off from the positive side of the battery line like I did.  The switch then only has to be able to handle the bat's 1.5 volts and mA's and I believe my switch is rated for at least 12 volts and probably much higher.  (I got it from Home Depot)  My switch is inline (series) with the lead coming off the + side of the battery...it then goes out of the switch to the 35 ohm wire wound rheostat and then to the base resistor (VR in this case) and then to the base.  You should not have any problems this way.

If I am still not understanding your problem, then ignore the above.

Bill

[Mk1]

@all

I make a proposition , first lets make a jt that truly makes ac , then lets make a real mag amp.

There are some really knowledgeable people around , i wish we could all make it together , i know Jeanna is up for it .

What do you guys think?

Mark