Joule Thief

[jeanna]

Another neon JT test using toroid with 10 and 100 turns. This works with base resistor as high as 2500 ohms and only uses 16.1 mA from battery to light the neon. So it seems that using more turns on the collector coil does provide better performance (lights neon with less battery drain).

So xee2,
I have never used a neon for anything. I can go to wiki, for info, but I assume it is a high voltage number that takes few amps. Is that correct?

I want to ask about the way you are winding your toroid. Since you only have 2 wires, the only way it would shift back and forth would be if the 100 turns were starting in the same place and going in the other direction from the 10 turns. You have already said center tapped, and this is what I am stumbling to describe.  Sort of like the MK1 only stripped down into 2 wires and 2 directions. Is this correct?

thanks,

jeanna

Oh yes, one more q. A long time ago you said that transformer in the camera circuit had was it 720 or was it 1720 turns?? Did you count them? did you calculate them?

thanks

[gadgetmall]

[quote @TheNOP  ]
could you please get what lead are for witch coil ?

you will have to de-solder the transfo to read resistance between each pins.
if you could also mesure the wires size too, it would be great.
thanks
[/quote]

what ? Not me Bro i got light 

[gadgetmall]

good going xenomorphlabs
sort of like bell labs only different... 

@gadget and all,

I made some progress on the tank. Here are some numbers

base resistor 453r
toroid 5+5 bifilar and 50 turns secondary
Variable resistor parallel with cap in line between base resistor and  toroid.

Testing variable resistor and 3 different caps 101pF, 103pF 104pF (I want the one in the middle!)


VR= 10K6r  101pF  7.68mA  light on
                  103pF   6.9mA   light on bright
                   104pF  6.4mA   light on less bright


interesting

jeanna

SEE that is what i was trying to tell everyone but i forgot most of my Glossary(had a brain stroke 2.5 years ago ) . Thanks for reminding an old radio head that  is was a dang Tank circuit . SHEEEEsh ....
Al

[gadgetmall]

the most important parts of the fuji jt is the transformer and its transistor.

i would like to know how this T1 transfo is winded relative to the schematic in this post
http://www.overunity.com/index.php?topic=6123.msg155334#msg155334

also, the resistance/wire size values would help to build a same ratio toroidal transformer.

the transformer must not be in a circuit for the ohms mesurement to be valide.

Hi . Oh . No i got no idea man . Maybe some one else will tear theirs apart and unwind it and have calibrated eyeball and tell you the size of wire . i can make a guess   All i know is i can Mod the sucker and get 12 hours of CFL light for free . and i explained the best i can to do the Mod .. ...thats all i really know ..  I would say 15 turns of 26 -primary - 1750 turns secondary of 36 .. two legs are not used that i see on my board

[xee2]

@ jeanna

Yes. Neon is high voltage low current (but more current than LED). It proves that there is over 90 volts with at least some current. If neon lights then it is possible to light lots of LEDs connected in series.

No. My windings are not center taped (I never said that). They are two separate windings. It does not mater which way coils are wound but they need to be connected so that they are polarized as in diagram. Best way to do this is connect it and if it does not work reverse the leads on one of the coils.

One of the Fuji schematics showed something like 1750 turns. I do not remember the exact number.