Joule Thief

[xee2]

@ Yucca

hi xee2

here's the flyback schematic with pin labels for the samsung flyback.

Thanks.

[Yucca]

@ Yucca

Thanks.

No worries, when your flyback arrives, just doublecheck and DMM across the drive and trigger coil pins, across pins 9 and 10 you should see ~0.6 Ohm across pins 1 and 2 you should see ~1.2 Ohm. I look forward to seeing it running.

[jeanna]

@ Pirate88179

This circuit runs for 30 seconds from the 0.047 F capacitor after the battery is removed.
....
The LED is illuminating a piece of paper 6 inches in front of the LED. For the first 20 seconds the LED is bright enough to see what is on the paper.

Hi xee2,
I have 2 questions to ask you.
Q#1
I cannot find where you tell how long the charge time was?
Was it instantaneous?
I can get 4 or 5 seconds from a mere touch to turn the light on then let it run down.
4 seconds of on and it takes 26 seconds to go out, and the components are different etc. but I would like to know how long the charge time is for the 30 sec run time.

Q#2
I have been thinking about the ignition coil.
I measured across the 2 screws and the amount was 2.2ohm.
When I measure from either of those screws to the end of the secondary in the pipe, I get um 13 ohm... I forget exactly, but the point is it is the same amount.
I am still trying to figure which is the primary that is connected to the secondary. There is a + and - sign on them, so which is the 'twisted pair or center tap'? Would it be the + just like my joule thief + side?

I don't dare touch this to anything until I can get this answer!
But, I would like to try it outside on my EB and see what goes .

thank you,

jeanna

[xee2]

@ jeanna

I can get 4 or 5 seconds from a mere touch to turn the light on then let it run down.
4 seconds of on and it takes 26 seconds to go out, and the components are different etc. but I would like to know how long the charge time is for the 30 sec run time.

Great. What size capacitor are you using? My 0.047 F caps reach full charge in less than one second, but I usually leave them connected for about two seconds just to make sure they are fully charged. I think the time it takes to charge will be a function of how big your capacitor is. Bill says his 600 F caps charge up really quick, but I still find that hard to believe. Are you going to post your circuit?

[xee2]

@ jeanna

I am still trying to figure which is the primary that is connected to the secondary. There is a + and - sign on them, so which is the 'twisted pair or center tap'? Would it be the + just like my joule thief + side?

My secondary is 11.6K ohms. I could not tell which side was connected from the ohms readings so I just tried both ways. The results I got were the same both ways. So I guess it does not matter.