Joule Thief

[electricme]

@all,
I just found this little place on the net, it could help people with calculating.

Resistance Chart      Power Wheel wall chart       Power calculator

Trey this link here  http://www.leonaudio.com.au/res_code.htm

and for a ceramic chart, try here     http://www.justradios.com/uFnFpF.html   


jim

[stprue]

I think you have it!
hooray!

let-r-rip!

jeanna

I now know/think I know why my recent coil didn't work!  I was going between every wire but to do this my crossovers alternated one in the going accross the front of the winding and one going back across over the winding.  Maybe the fields cancelled eachother out!

[stprue]

@stprue,
Thanks for your interest in what I am doing.

I have made a crt of the 1st experiment I did with my 7 toroid primaries in series.

jim

Well it is very interesting work to me!  Have you seen any benifits to this set up in conparison to a single coil set up? (Data)

[stprue]

NICE my 100 20,000mcd leds have just come in

@Pirate

Can you let me know where you got your magnesium and carbon from?

[resonanceman]

I have been busy.

It  has  been  a few days sense I have had time to read  any posts here .

I am going to  post  a little about  my new JT

I am calling it  LM1 

Sorry I don't have any pictures
I tried to send  some from my  phone but they did not  show up for some reason .


This kind  of  JT requires a lower  voltage LED  than most .  I am using  a red one .  (2 V )

LM  stands  for  Lazy Man     
So it is pretty easy to make .

I started  with  a full coil of red Radio Shack magnet  wire .
That is 200 ft  of  #30 mag  wire for the non Radio Shack people here . 

This  wire comes with the  start of the wire  sticking  through the   center of the  spool .
I sanded  the enamel  off  both ends .............OK ...... the secondary is finished  .
It is time for the primary .

You have to understand how to  tune a coil to make this kind of  JT .
There are MANY options for cores  ...... 
I have found  that  around  15 wraps bifilar  works well with no core . (2 wires each about 6 ft )

Using  2 Electronic Goldmine 5 for $1 toroids in the center of the spool  works well at around 8 turns


This is  a low power JT but I have been  getting  good results  with it .

I am working on  a driver  for  a 60 LED array  out of a LED floodlight .

The  basic  LM1  isn't strong enough to light  this array. ( 1.2 volt   AA  battery ) It  runs  around 50 volts with only the  original JT LED 

For LM1.2   I used  an empty Radio  shack  spool  and  put some #38 mag wire on it .
The wire broke when the spool  was maybe 1/4 full   ( about the same as  radio  shack  puts on them )
I did not look it up ........but if  someone remembers  how many ohms per foot  #38 wire has this coil  is 355 ohms
I put a temporary primary on it .
The temporary primary  was made  with a pair of wires from a cat5 cable
6 wraps ( 32 in )
160 V  with no load .
Driving the array the voltage drops to 74 V     
The  array is by no means at full power . It is more like 1/4 power
I intend to power it  with an 18 V battery eventually. 
I  tried 3V it was MUCH closer to  full brightness .
No  core on this JT
I would  have tried it with  a toroid or 2 but I would have had to  cut the wire  off of  some  of my old  JTs first .
I  think  that  the JT will handle   more power  with  the toroid in the center.
The voltage  drops  slightly when a core is added (at least if it is tuned for no core)  but the LEDs got brighter

gary