Joule Thief

[resonanceman]

I am  playing  with  my 3rd JT 

It  is wound  with  4  wires  plus  a shorter wire for  the  connection to the   transistor base.
15 turns  for base ......I think 22 for the  other 4
I used  the  black  toriod from  electronic goldmine    at  22 wraps I could no longer get the wires through the  center of the core . .

I wound all the wires at the same time ...like one  large wire.

I expermented  a little  with  a cap  on the  transistor base leg ....... I ended  with a .1uf     with the pot  I am using  this  combination  allowed adjustment  from  a few flashes per second .....to very bright  near the other side of the pot . 

One  question .     when running  full  brightness  the  transistor  a 2N3904 is  to hot  to hold  my finger on . ....is this normal ?




I have been playing  with  the "secondarys "
I pulled  the  " original "  JT LED out ......  I believe Jeanna  said it  used up   to much  current  in that position.

I am  low on  LEDs  need to order more.
Right now I have  all my spare leds lit up .

3 ultrabright 5mm  and   ultrabright  10 mm 
I am sure  that I could light more because  the LEDs that were already lit changed very little  when I added more.

The  last  LED that  I  hooked up  was  the led  I  pulled out  of the  original JT LED position .
I  only had one  set of  secondary leads left ......I had  the my DMM  hooked to  those leads .
My DMM  was reading  1.380  AC     when I hiiked up the  last LED  the meter went to 1.384
Can anyone  explain how  I can gain .004  by adding more load?
It  has been running  for close to an hour and a half ........  the  voltage   of that secondary  has been slowly  dropping ........it is now  1.354

I can't wait toget some more  LEDs and  load this thing up ?   

sorry if  this  stuff is way behind what  you are doing .
Part of  why I am posting it  is  for others just starting out .

gary

[jeanna]

Hi Gary,

First you are not way behind.

Yes, Isn't it strange how you can get higher voltage when you add another light? I have had this happen too.

I hope you can give a better description of what your wires are like. I mean, what of the 5 wires is doing a back and forth dance and what ones are straight? At the moment they sound independent of each other except as they are all effected by the mag field of the toroid.

Did you say you are using a 1kohm resistor at the base?

I never get any heat. I believe it is because I always protect my base with at least 480 ohm resistor, and that is when I am adding the 20k pot to the 480. I think heat is because too much voltage therefore amps is going through the base.

Oh also, do you have a bridge rectifier you can temporarily put on your secondary? This will give you the rectified volts. I think you may be surprised how much voltage you are producing there.

thank you,

jeanna

[resonanceman]

Hi Gary,

First you are not way behind.

Yes, Isn't it strange how you can get higher voltage when you add another light? I have had this happen too.

I hope you can give a better description of what your wires are like. I mean, what of the 5 wires is doing a back and forth dance and what ones are straight? At the moment they sound independent of each other except as they are all effected by the mag field of the toroid.

Did you say you are using a 1kohm resistor at the base?

I never get any heat. I believe it is because I always protect my base with at least 480 ohm resistor, and that is when I am adding the 20k pot to the 480. I think heat is because too much voltage therefore amps is going through the base.

Oh also, do you have a bridge rectifier you can temporarily put on your secondary? This will give you the rectified volts. I think you may be surprised how much voltage you are producing there.

thank you,

jeanna

Jeanna

I tried to explain  the  wires  in as much  detail as I can
Not sure what you mean by back and forth  dance .
The  5th  wire .......the  short one  went  to the  base of the transistor .
One  end  of  the short  one connected to  one of the other wires ........as in the basic   JT  schematic  you  posted .
That left  3 wires for  secondarys 

I  am using  a 1K pot ......with  the .1UF cap   the  wiper  is  near    to the  end of its  travel ....... I  am not  sure if that is near 0 resostance or near 1k ....... I did not measure it yet and I  don';t know much  about RC resonance .....    at the  other  end of the pot  the  lLEDs flash maybe  once a second   .


..I  got a couple  bridges ....I  will play with them tomorow .


.I am  going to order some more  LEDs  then call it a night   


gary 

[Mk1]

@all

I sneak peak at the mk8.

The meter is connected to a high amp diode rectifier it lowers the voltage , in a big way , but i still have good stuff out , the meter is connected to only one coil, so 15 left.

No Claims here. except canadian tire have nice and cheap meters.

Mark

[weri812]

hello all

@is  that is a vfo "variable frequency oscillator"  or use  a pll  "phase lock loop"  and a  vco  "voltage control oscillator"

all will give a variable frequency.

God Bless
wer