ok i got what I'm looking for now. but how would i put these two circuits together so the LED AND the solar work right.

Picture attached.

i have my ferrite wrapped like in :http://www.solarbug.com/whiteled.html

Attached Images

2curcuits.jpg (23.5 KB, 24 views)

 

Would this work?


pic attatched

Attached Images

new-circiut.jpg (27.6 KB, 17 views)

 

ok call me an idiot. i built this one here:


was working GREAT. then what do i do? forgot the battery was hooked up and grabbed the LED leads to bend and get to fit in my 35mm canister. Then the LED was REALLY dim. took it out and replaced it. nothing now. replaced the transistor and metered the resistor. all good. the only thing i can think of is the ferrite. could i have burnt it out? i'm only getting 1.5 volts at the LED leads. man i hope i did not burn it out. that was a mother to wrap. had to do it 3 times. about 30 minutes each time. please leave me some input. i'm off to bed.

thanks guys.

 

hi,
Nice to see you are a component scrounger/recycler, its suprising what you can find on old electronic items.

It sounds as though the circuit is not oscillating, that could be due to a number of causes..
You have changed the LED and transistor correctly and with the same type???

It maybe a shorted turn on the ferrite, check the windings for contact with ferrite ring.. dont worry about burning out the ferrite, its not going to happen.

Is the ferrite cracked across its annulus?

Do you have a dry joint on the winding due to the enamel coating?

Lets know what you find.

BTW,, S/H is second hand and PSU is power supply unit, its an easy way to write, bit like BTW!

EDIT: can you post some data for the solar cell you are using? .. Volts/mA etc

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

Hi Hero,

I bet you know this, but just in defense of the guy (Richard Cappels) who originally built the nail-as-core circuit: it's just to prove that it can be done, and that the inductor value is not terribly critical (somebody correct me on that last one if I've misunderstood).

But I do agree with you: don't try using a nail or scrounged bolt or something. Or do, but not with high hopes. I got a week's runtime (7 days 5 hours, IIRC) out of a bright white LED using this circuit from the same page: http://www.cappels.org/dproj/ledpage...d_Garden_Light using one AA Energizer. I think I used 4401 transistors. I used a generic ferrite toroid core and put on the recommended 20 wraps-tap-20 wraps of green Radio Shack* enameled magnet wire. I haven't tried the nail yet.


Torben


* - I hate saying "The Source by Circuit City".

 

i give up for now. i have done everything. redid the ferrite, re did the whole thing from scratch and nothing works. still only getting 1.5 volts at the LED.

 

hi,
Sometimes its better to walk away from a project for a few hours, come back with a clear head.
Its probably something so simple you are overlooking it.

Lets know when you come back on stream. EDIT: remember give us info on the solar cell.

As a last resort, we could sacrifice a chicken or something in order to placate the project gremlin gods!

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

Did you use a flashing LED with the voltage step-up circuit?
When the LED turns itself off then there is no load on the voltage stepup circuit so the voltage skyrockets to a very high voltage that destroys the transistor and the LED.

I hope you know that the two coils must have the proper phase for the oscillator to work.

__________________
Uncle $crooge

 

Did you check the phasing on the coil?

Try swapping either the feedback or driver connections round and see if that works.

__________________
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Make a center-tapped coil which is easier to wind because it has only 20 turns of doubled folded wire, then its center-tap is obvious, the two ends have the correct phasing and it doesn't need a pcb.

Attached Images

Joule thief.PNG (12.0 KB, 9 views)

__________________
Uncle $crooge

 

You mean a bifilar winding?

That won't help because the middle tap will need to be broken and the oposite ends of the each coil will need to be connected to each other.

__________________
I also post at the following sites:
http://www.stop-microsoft.org http://www.heated-debates.com
Screen name: Aloone_Jonez

 

I see what you mean. The two coils must be in series for them to be a single coil with a center-tap.

__________________
Uncle $crooge

 

why not use the good old LM3909 CHIP TO BOOST THE VOLTAGE it only needs a small cap to boost the v output to a led and it produces good flashers for 3mth from a AA batt maybe longer. and it will fit in a 35mm can .

 

The old LM3909 is obsolete and has not been made for many years.
Its datasheet shows a pretty big 300uf timing capacitor.

__________________
Uncle $crooge

 

na 100uf even 50uf made very good pulses yes maybe its atleast 20+ years ago . dunt time fly