Joule Thief

xee2 · February 04, 2009, 02:24:55 AM

I was able to light a neon bulb dimly with a normal JT circuit by adding a cap and changing turns ratio (also used a big toroid).

gadgetmall · February 04, 2009, 03:16:47 AM

Quote from: innovation_station on February 03, 2009, 09:04:53 PM
i feel like a yo yo lol

errr

you guys build gadgets unit plerase show CLEAR PICS and all mods ...

when you get it finial i will then build it

im gonna build the new mag amp .... with a feroite transformer core ... and the PROPER JT

i think it should have 2 transistors 1 out put coil secondary ... 2 bifillar windings oppesit each other ... left and right hand ....

will build this tonight too ...

ist!

GADGET CAN YOU PLEASE MAKE A TUBE VID TO CLEAR THIS UP SHOWING RESULTS...

Hi WIlliam . IF i had some MONEY i would buy a Decent CAMERA . . My video camera is a hacked CVS video camera i bought for 3 bucks . and my still Camera is a casio i bought on ebay 7 years ago that has a macro switch on it but no zoom so they are as clear as i can get em .. Sorry

gadgetmall · February 04, 2009, 03:21:20 AM

Quote from: xee2 on February 04, 2009, 02:24:55 AM
I was able to light a neon bulb dimly with a normal JT circuit by adding a cap and changing turns ratio (also used a big toroid).

So the Turns ratio is not 10 / 40 ?

xee2 · February 04, 2009, 04:01:30 AM

@ gadgetmall

Quote from: gadgetmall on February 04, 2009, 03:21:20 AM
So the Turns ratio is not 10 / 40 ?

Turns ratio is as shown in diagram. Normal JT is usually about 10 and 10. Actually neon is bright for a neon but that is dim to me.

gadgetmall · February 04, 2009, 04:06:51 AM

Quote from: jeanna on February 03, 2009, 08:10:00 PM
This is just a bit more. inspired by what ist just said, although I am not sure what ckt the comment was about??

I just changed the cap on the base resistor which is now 2.2k down from 4.7k (but it is the same for the following:)

Using 100pF the lights of the secondary dimmed a little, but easily seen change.

Using 10,000pF, the lights of the secondary brightened BUT the cost!! The amperage went up 10 times!

@Gadgetmail, you said there was some tuning involved and you ended up with the 68pF. The closest Radio Shack had to 68 was the 100pF and my next larger size is100 times greater and the use was 10 times greater.

The change went from 2.5mA with 100pF (it sez 101) across the base resistor, to 23.6mA with the 10,000pF (it sez 103)

With more amps there was more light. (I don't think 10 times more though) I think I will shut up for a while and wind a new toroid so I can make some planned changes. syl.

thank you,

jeanna

You are at the right spot when the lights got brighter and the current went up . replace your 2.2 with at least 5 to 10 k . I can tell you that the effect of current drop is VERY DIFFERENT using a little carbon vr with the little cap across the legs of it then using the wiper and one end to adjust it THAN using a hard resistor . I proved that to My self .total two different outcomes using the exact same resistance set with vr verse hard resistor . I think the Vr has a little reaction going on with the metal or contact . maybe like a using coil a bit . i don't really know but i thought it worked better on Jt's.

Oh and Jeanna - My HANDEL IS GADGET MALL not GADGET MAIL