Joule Thief

[jeanna]

@Detrix42,
May I recommend a scope?
Mine may not be very good for posting pictures but it is flexible, portable and very handy, and at $180 it has more than paid for itself in helping me get the answers I need.
A freq gen will not give you as much information because all you are doing is controlling what you put in. The real information comes from learning what you are making (at least that is what I think. )

It was because I had my scope hooked to the secondary wires while I tuned the resistor that we all learned that when the voltage goes one way the frequency goes the other, at least in a joule thief.

Anyway I bought a HPS10 by velleman, and I recommend it.
You can spend a little more and get a back light so your pics will look good.

That and an induction meter really did the trick for me.

jeanna

[innovation_station]

I have been doing some research in the TPU thread.  This is supposedly the natural frequency of Earth's magnetic field.  I thought if you tuned a JTC to 175KHz, this would resonate with Earth's magnetic field and use Earth's magnetic field to generate more electricity.  I have taken the core out of a flyback transformer, and want to tune a JTC to 175kHz with it, and see if I get any extra juice. 

Detrix42

: )

well you dont want to tune right in .. as it will blow ..  a  freq genny at 180 and a magnet .. on the core  probally do the same ...  OR YOU CAN HIT ANY HARMONIC YOU CHOOSE .. ; )

if you buy a scope .. for god sakes get an OLD ANALOG ONE ... try for 50 mhz min .. dual trace ..

: )

ist!

@ j i didnt need a meter to see the MOT has a short fat wire and a long skinny one .... : )  lol

is it a 2 part fly back core ...  i was thinking of maybe building a syncotron  but putting magnets between the out side and putting a pancake on the inside split ..  then jt the 2 half cores...  but so they BUCK THE MAGENT at 175....

like this

11111                 m = magnets  like poles forced togather
1      1
m     pancake
m     pancake
1      1
11111

the more i think about this is this ...  first you pulse the pancake a few times ..  you recover from the flyback core to a cap that powers the jt wound on the core ... ; ) 

so then when your jt's are running at high voltage and pushing back you pull from the place you energized the device from ..  a device like this requires a jt that runs with gain ...  that means low low ma draw high high spikes ...  long wire ... and a short fat one ..  : )

[tysb3]

hi,
@ Pirate88179

Qx5252 same as JD1803

http://pdfaz.com/download/qx5252-5106270.html

http://translate.google.com/translate?hl=en&sl=zh-CN&u=http://search.china.alibaba.com/selloffer/k-JD1803%25B2%25DD%25C6%25BA%25B5%25C6IC_n-y.html&ei=qoXYS4adK4T4sgPatNSdBg&sa=X&oi=translate&ct=result&resnum=5&ved=0CBkQ7gEwBDhG&prev=/search%3Fq%3Djd1803%26start%3D70%26hl%3Den%26sa%3DN%26rls%3Dcom.microsoft:en-us:IE-SearchBox%26rlz%3D1I7ADBS_en

[detrix42]

Hi, everyone.  Just wanted to show off a little project I did for my wife.  She had a tin that she wanted used to build a joule thief flashlight.  Just a little show and tell.  Nothing special here, just wanted to show it off.   

Detrix42

[mscoffman]

@all:  I need some help here.  I do not have an oscilloscope, and so I can't do this my self.  I would like to know exactly what is necessary, component wise, to get a joule thief to oscillate at 174,926Hz.  Or let me know if this is even possible.  Thanks for any help.

Detrix42

Get a JT that can operate at slightly over this frequency. Then
get a  quartz crystal cut for this frequency. Attach the crystal
leads to various points in the JT untill it locks in. Make sure you
are not "stepping" on anyone during its use.

:S:MarkSCoffman