Joule Thief

[jadaro2600]

Hi . you dont need two batteries . One will will run a 555 . they will operate on very low volts and current if given the proper circuit . . So they are juts like leds in a way they are all measured at dc values not PDC . PDC will run brighter with less current . . Yes its cool that you are trying to reinvent the inverter , i want to too but run it off the earth instead of Mucho batteries . Lets .get to work !!

Gadget ..

This isn't exactly what I was hinting at, but ..

I was more referring to using two separate energy sources, one to power the 555 and one to power the JT.

[electricme]

@Jeanna

I am taking a liberty her and reposting your Berry and Widdow JT (which appeared midway down on P482) test, for the purpose of us all here to go over it again.
You have started another JT setup you know, don't you? This is another way to use the JT as a POWER SUPPLY.


I recommend us all to take a look at this again, and see if we can improve on it, if this is OK with Jeanna, of course.

This is similar to what I did wayyyy back just after I joined this thread, but I didn't think to piggyback another JT powered by the FIRST JT
I went on by powering another torid, which if I recall it had a "primary and a adjustable "secondary" which had "taps" coming out which had a 12gang switch so I could "select" whatever output I need at the time.

OK everyone,
While you were all typing this morning, I was trying out something I have wanted to test for a while.

This is what I called a piggyback a few weeks ago. For non americans, it means one carried on the back of another.

I wondered if the hay-wagon could give a lot more free rides.

First I set up a bjt using the one from the pic this morning. That is the 'berry'
the berry has 11T,11T with 36T2^o
I tested its amps and stuff

Then I took the berry's 2^o wires and tried two different things with them
1- I put them through a full bridge then into the battery rail of another jtc
2- I put them straight into the battery rail of another jtc.

This battery rail is the input for a second jtc which is pretty closely matched.
I just named it 'widow' because it is black and red.
it has 5T, 8T, 40T 2^o

There are 2 breadboard circuits.
Both use 2N3904
around 800-950 ohm resistor at the base of the transistor.

(I know,I know, I can get more bigger results with lower resistance here. This is a study.)
The battery is starting to run down. It is at 1.31v.
===
here goes:


I used the berry for the first jt

The first jtc draws 26.2mA by itself.
When the secondary wires are passed through a full bridge it I can collect 22 -37 volts in a cap(wow)
Also from the secondary, the scope sees 8.22 v with 1 wave showing at 120 kHz.
We already know this berry lights lots of leds 5 in series or 29+  in parallel.

[I also checked out using a 3 volt battery, but more on that later.]

Then I put the widow into its own breadboard.
This by itself draws
33mA with a led
38mA with no led
Between the secondary wires, the scope reports
11.5volts with no led
6.9 volts with a led in the bjt place.

==

Now for the fun

I put the secondary wires from the berry through the bridge then jumpered them into the battery rail of the widow.

The bjt led of the widow actually went on although dimly,
The secondary wires from one jtc actually started up a whole second jt circuit!!!!!.]
I tried using a 104pF cap across the transistor base resistor and it did not help with the light or it was not noticeable.

MK suggested I try the piggy back without rectifying and so I stuck the secondary wires from the berry straight into the battery rail of the widow's circuit, without rectification.
This must reduce the effect by half since the rail is designed for dc from a battery.

The light went on dimly.
I used the 104pF cap in the base resistor place and the light steadied. It was still dim, but no longer flickery.

Now, I checked the widow's secondary wires 2 ways.

1- through the full bridge.and collected in a cap it filled the cap to 1.4 volts (not much but more than the starting battery.)

2- Without the bridge the scope reported 0.51 volts between the 2 secondary wires, (even without the led and 104pF cap)
and the widow's secondary cannot light a led.

===
Oh, and with both circuits going, the amps draw was 27.8mA higher than the berry alone, lower than the widow alone.

After a rest, I will reverse the places of the 2 circuits and put the widow in first.
-===-==-

I am pretty happy with this.
That it works at all is amazing.
I think it will be possible to find an amplification.

I would like to find a way to put the secondary from the berry directly into the toroid of the widow to get its vibrations going without the effect of the rectifier or the battery rail.

Maybe if I put it across just the base it will start up the second transistor.
Then would I use a cap across the C and E?
Hmm starting to sound like Stubblefield.

I better take a break!

thank you all,

jeanna

I took a picture of them both  piggybacked lighting a light.

Jeanna, if you have this circuit, might you post it here please.

jim

[electricme]

@all,
Got myself a whole lot of Green LED's,    saw this at the Dalby scrap place I frequently go to, I took the chance they would all be blown, Payed about a $5 for the lot, they had been exposed to the weather, got a bit dirty, but they all work, he he.
So what is it? It's is a green traffic light
What else did I get? well a heep of Torids on 3 circuit boards, along with some big relays and thyristers and neons.

AFTER FEASTING ON THIS LOT, go back and read Jeanna's item ABOVE.
see if you can understand it

jim

[jeanna]

OH Jim,

It gets even better!

I will post today's wonderfulness as a schematic so you can look at it right away, then I will add to the post with an edit later so they are together, and I will be explaining it.

wow. you really got some prizes today. ye shall be known as, "Jackpot Jim".

,

jeanna

EDIT

To explain.

I added some sophistication by re-naming this as a 2Tier Joule Thief Circuit. This explains itself.

Also, Most of the following description is what I did with the second tier. If I did it to any element of the first tier, I say so.

The first tier is a pretty straight forward joule thief with secondary.

Widow Toroid - "Charcoal Tor-23"  5T,8T,40T2^o
2N3904 Transistor
237Ohm Resistor at Base of transistor
1.35v battery

The secondary is fed into the - and + of the second tier battery rail.

XTree toroid "Charcoal tor-23"  7T,7T,116T2^o
NO transistor
NO resistor at base either
BJTLED is necessary and on
3 LED in || running off the secondary
The orphaned JT lead with no transistor connects to the - side of the Secondary leds for increased brightness.

Once it was going I tuned the base resistor on the first tier to achieve best brightness. This was 237 ohm as drawn.

When I removed the second transistor and saw the lights all stay on and maybe get a bit brighter, I looked around for a place to stick the orphaned lead from the toroid.

Connecting it to the - battery rail (second tier ), all the lights went out.
Connecting it to the + battery rail (second tier ), the BJT led stays on, but all the secondary leds go out.
Connecting it to the - of the secondary set of leds all the lights stayed on and the secondary fed lights got a bit brighter.

Since the led is a diode I replaced it in the BJT position with a 1N4001 type diode (the only kind I have) observing polarity and all the secondary lights went out.

I can put the BJT led into the - and + slots of the 2nd battery rail, but the secondary lights go out. This may be because I am limiting it because the bjt is a yellow and the secondaries are white.
The BJT can be white. BUT not in the battery rail. It won't light there.


Finally I checked the amps draw at the battery, because it seemed to me that there was much that was dependent on a good flow.
It was 54.21mA so, it was drawing a lot. And when I connected the battery + in series to the 10 ohm resistor for checking the amps, the secondary lights (on the second tier) went way dim.
If I use a bright white for the BJT of the second tier, the amps draw goes down to 52.6mA.

I am no longer working with matched bright whites. I will spend some time to match a few, I think I am confounding a few things I don't need to by using unmatched LEDs.

But, anyway...

YES!

jeanna

[Pirate88179]

@ Gadgetmall:

Thanks Al, good to see you again.

@ Jim:

Nice find at the scrap yard!!!  I ran across a place on the net that sells used traffic lights....just the leds....I'll see if I can dig it up.  Good way to get a bunch of them.  Nice toroids!  Looks like some of them are pretty thick, you will have a lot of fun with those I'll bet.

Bill