|Renewable Energy Discussion on various alternative energy, renewable energy, & free energy technologies. Also any discussion about the environment, global warming, and other related topics are welcome here.|
negative-R -- still confused...
Thanks for the explanation ... but I'm still a bit confused by
this phenomenon... You seem to just accept it as if its no big deal.
My understanding is that negative resistance is suppose to be impossible.
It was a highly debated topic among physicists ... or so I understood.
Perhaps it is just a debate about semantics.
HP has announced a break through with memristors --
claiming they will be able to make very small memories now -- or
so they hope.
This seemed like a huge deal ... and yet I find that
NEON ... and other gases have had this property all along ..
and it has been known about for more than 100 years.
So yes its seems that OHMS should be a measurement that
is ONLY positive ... so that we can keep our sanity.
If you measure a circuit ... and end up with a calculation producing
negative resistance ... there is some unaccounted for effect.
Take Mutual Induction & Non-Conservative fields.
If you were unaware that mutual inductive fields were affecting
your circuit in some way, when you measured things ...
and calculated the value of some resistance, you might find
it is negative ... not because you did your math wrong ... but
rather because you failed to account for the energy entering
your system from the outside due to mutual induction.
So lets take a close look at NEON here. It is established
that the curve is non-linear ... and there are parts of that
curve that exhibit a negative resistance like behavior.
But WHY? Is energy entering from the outside when ionization
occurs? Yes we know this occurs due to ionization ... but
do we know WHAT occurs?
That is my question.
Last edited by morpher44 : 11-17-2009 at 06:47 AM.
@ Jeanna & All
Here is the video of Jeanna's big JT toroid coil in action. I changed things around a little and ran a small 10W gutted CFL on it with one AA. It is a pretty neat little light folks. The circuit diagram that I show in the video has an error on it. She called for a 100pf cap between the base and the negative rail and I just eliminated it. There should be no connection there to the neg. rail. As of this posting the "little light that could" has been running for 14 hours. I turned the brighness way down to a current draw of about 50mA to do it.
This would make an excellent emergency light. One of these in each room of the house and a few AAs would really help. The pleasant light would cheer things up. Kids would get a kick out of it.
YouTube - Jeanna's Light
Last edited by Lidmotor : 11-17-2009 at 07:46 PM.
As it happened...
I was unable to watch your excellent replication video because the lights went out last night!!
So, Thank you for making it so clear and simple for everyone.
I love the way you nested the light inside the toroid. It makes it a very nice package. (Maybe better than a basket! )
I am collecting a small supply of those cfl's.
I used to have the kind that didn't ever burn out, but now more and more they overheat and I collect them.
BTW, I have never had any heat from my circuit at all.
I am wondering if you used the rheostat as a precaution, or if you actually got heat on that transistor?
Thank you again.
It was my experimental 30 light circuit that lit up my living room during the power outage.
I was very pleased to find that when there were no other lights anywhere, the light from the 30leds in those 5 circuits was enough to light up the room to the point that I could see everything.
It was way more light than just enough to keep me from bumping the furniture, and way way more light than a candle.
I have made that mistake since the first joule thief I ever made.
I did not mean to perpetuate it here!
It is the emitter that connects to the neg rail and that is all.
The 100pF cap is actually in parallel with the 90 ohm base resistor.
And that is, of course on its way to one end of the jt bifilar.
On other jt circuits,I do not usually add a cap in this spot, but it often seems to reduce the amps draw, and so it helps a lot when lighting a fluoro light.
All day fun with the new light
I worked with the little light most of the day and guess what---it is still running on that one AA (dimmed down & set at 50mA). Amazing. I played with the 10T secondary trying different inductors like you suggested and even ran a second JT off that winding. One of the best things about this setup is that the toroid (at low settings) does not make much noise. There is not much heat generated either-- unless you UP things then you get noise and heat. I may box this up and use it on my boat. It makes a nice table light.
What is your 30 light circuit like? Hum a few bars and I'll try to play it.
I think this work is really really important.
There will always be storms ... lights will always go out.
What a comfort when one of you "light workers" can bring
in your goofy technology with eyeballs (yes you Lidmotor)
and make all the kids calm down and feel comforted
because the room is lit.
Electronic light, when all the power fails, is like a chain-of-custody
back to the technological world -- which seems to have
darkened and failed with that nagging "single-point-of-failure-grid-mentality"
which we know is a recipe for disaster .. but never seem to do
The "light shaman" & "light workers" will save the day since
they have practiced on this forum and perfected their magic.
I encourage those spectators out there to crack open
some basic electronic books, learn how to read a simple
schematic ... and try to make this stuff.
You will be a highly prized "light shaman" during rough times!!!
Good work gang!!!
It is interesting that low resistor settings it doesn't make much noise. I have not had lees sound unless it went above my hearing which is higher resistance=higher frequency.. Very cool.
I never got any heat either. I am so grateful to you for making a replication(s).
Yes, I hope you do make it for your boat... then I can make a replication from your ideas!!
This thread documents everything I did.
It is not too long, but I understand wanting to cut to the chase.
So, here is the schematic.
As you saw today, adding inductors (coils) in series is a very easy and effective way to boost the power you are getting from a set of pulses. (not to forget that it allows all the secondaries to work at the same time.)
I would like to know the numbers details of the inductors and caps, and the frequency of the additions you made.
Very little has been done on this since it got buried, and I would like to start seeing/writing some principles for others to be able to draw from.
So, here is the schematic.
I am open to answering questions. (if I can guess the answers, that is.)
I wonder if a new thread just for this would be a good idea? But for now, it is here.
It is also the subject of the part6 video
jtc video part 6
Last edited by jeanna : 11-18-2009 at 03:44 AM. Reason: add
I am wondering if this thread spelled "Theif" wrong because
Joule-Thief(TM) is a TI trademark.
I was a bit bummed to learn it has been trade marked.
Texas Instruments, Energy harvesting becomes reality with AdaptivEnergy’s wireless, remote solutions based on TI low power technology*|*Texas Instruments
Fly Back Transformer????
Thanks for the info on your multi light circuits. I watched several of your videos and I understand what you are doing. The way that you are running the leds in series reminds me of the SEC circuit only different. That circuit is a finely tuned RF resonance circuit that drives the leds through one wire and an Avenmenko plug.
Anyway---in my internet wanderings this morning I found this:
POWERLABS' High Voltage Solid State Flyback Driver
It looks allot like what we have done here. We may have built a sort of fly back transformer. I have a couple of TV flyback transformers and I may fiddle with those today.
Joule Thief? Joule Theif? You say toomatoe. I say toemahttoo.
I found out about the patent on the name awhile back. I think that this patent idea is slightly outdated. The orient gets ahold of any new idea and has field day with it almost immediately. It ends up in the dollar store in a year or two.
Last edited by Lidmotor : 11-18-2009 at 04:45 PM.
Joule Thief Comparison
I had an idea that you of all people might be in the best
position to give data on -- since you've replicated so many
of these circuits.
A good way for us all to compare these "big joule thief" solutions
would be to have 3 or so metrics:
1. Cost-of-goods -- an estimate of the parts needed to make it.
We can standardize on some currency and people can convert
currencies using online calculators.
If you have a solution that uses hand-made stuff ... all the better
since people can scavenge parts from electronic junk ... making
the solution a bit cheaper for us all.
2. Steady-State-Power estimate: In watts
All we are concerned with is input power to drive the lights.
3. Light brightness: This can be a sort of subjective metric ...
such as what percentage of a 12'x12' room is lit or something.
I don't think we have to get too technical on this one.
I think having metrics for comparison like this will inspire
us to get competitive here.
Jeanna's Light solution looks pretty darn good at this point ... but
that is just the last one in my memory.
We should keeping raising the bar here ... and going for lower and lower
power, cheaper and cheaper COGS ... and brighter and brighter light.
Having it work on a boat on the water is extra credit.
Sitting around the fire
What you are asking for is something that I have been working on for years and the answer is complicated. Basically it all depends on what kind of light you want.
I watched a TV show last night on the evolution of man and one of the big things mentioned was that we became very social creatures. It is thought that this may have been contributed to by our sitting around the fire at night. It was a chance for everyone to get together, get warm, eat, stare into the light of the fire, and talk.
My experiments with the light projects on the boat were very revealing about what worked and what didn't. My 'Halo Light' became the "fire" that we gathered around at night and relied on. Why? It put out enough light, you could stare at it (warm light), and with solar energy-- it took care of itself.
This last season I bought a commercial fluorescent 4 D cell light that does about the same thing. It has an 18hr. run time and worked very well on the boat. The big difference was that I made the 'Halo Light' and we would talk about it at the table at night.
I wonder if ancient people sat around the fire at night and showed off their new inventions to others. I'll bet that they did. The conversation might have been: "That's a great spear" Yugg says to Bugg. In the back of Yugg's mind he is thinking---" I can make it better." ---as he stared into the fire.
Last edited by Lidmotor : 11-19-2009 at 03:52 PM.
OK, now make them in series.
when the leds are in parallel it is very bright and a wonderful solution to making a lot of light, but see if you can make them in series, because that will push you to higher limits.
(Now, I am getting silly. I have been trying to think of a way to use that beamup for some time!)
In my experiments up until a new design last week, I would get about 1 volt per turn on an average small toroid- joule thief secondary; and with these kinds of spikes the voltage doesn't count as high, so I usually figure about 5-7 volts per led.
So, if you are getting more than 20 volts you should be able to light between 3 and 4 leds.
If you get really high voltage spikes like 80v, you will pop all those leds which are arranged in parallel, so be careful. (all of us that are on pirate's joule thief thread at ou have popped multiple leds, so this is just a kind warning.)
Anyway... great going
@lidmotor et al,
I finally found where wall mart hides the led lights. Or maybe they just began to carry them...
These lights which have regular and candelabra sized bases come in several bulb shape and color.
They are made in usa by lights of america. They use 19 strawhat leds which have a little light diffuser at the top which spreads the light around etc.
The reason I am bringing it up, is that they are made identically but some are warm light and some are cold-bright-white-led color.
The effect on the ambiance of the room is real.
The yellower and surely less brilliant bright are very comfortable and calm to the senses.
Last edited by jeanna : 11-20-2009 at 01:24 AM.
Jeanna's Light---In a box
I was so impressed with the results that I was getting that I put your light in a box today. Now it is in a truely usable form and is more than just an experiment.
Thanks again for sharing. I left the extra winding on the toroid open at a port so that I can continue to play with different ways to use that extra 10 turn coil.
Here is my video of boxed up light:
YouTube - Jeanna's Light --In a box.ASF
That is a really great video, again.
I think it is a beautiful lamp and deserves a prize. Of course just being able to make such a thing is its own prize, isn't it?
I do not want to repeat the whole thread here at this energetic forum, but when I realized I was basically alone in my interest in getting the multiple secondaries to work and simultaneously, I decided to start my own thread.
I started out defining some goals etc, and some of them have changed, but it was on this thread that I described my progress with the experimental circuit. (the one which now has 30 leds in series as bright as the 10 original ones)
In my mind this is a miniature of what it would/could be, but it is a lot easier to do this experimental stuff with small voltage, because it is easier to tell when there is something.
I am bringing this up, because you are in a position to gather some more information and put all the lights on together, if you want to do that.
I think also, it is necessary to put the inductors in place if you will be making a self charging unit in there.
So, enough talk, here is the link.
my ac from the jt thread at ou
and again, thank you,
Joule Thief secondary AC output
I went over to OU and wandered around your AC thread. It is getting pretty long just like Pirate's JT thread. There is so much interest in this simple circuit and the spin offs from it. As far as AC off the secondary, you are right there are some real advantages to that. The big one that comes to my mind right away is that there is no "line loss". Isn't that is why we went to AC many years ago? You can run thinner wires to a distant point and not lose the juice. Induction motors are usable then also (has anyone made a tiny one that runs on a AA?). Maybe there should a prize put up for the first one to run an induction motor off the secondary of a JT. It is another thing to study and goes on my to do list.
I'm glad that you liked the boxed up light. It was a fun project.
I see the penny.
I thought it was the toroid when I saw it before.
I am not sure why you have stuck 2 toroids together (have you?)
So, it might be a whole new discovery. But for now...
Just wind 20 turns around your toroid and if you have no scope, then start with 3 leds in series. If the lights are too dim then take 1 out.
This is just a guess-gauge I am suggesting for you.
I think 20 will be safe for 3 in series.
Then add turns and lights, using the same lighst/turn ratio.
Have fun and keep posting your results, please.
Last night I almost removed the link to my thread, because I looked at it again, and it is so complex and hard to understand.
Here is a story which explains a little of how it happened:
I had the idea that I could start a second joule thief from the output of the secondary from a first one. (I called it a '2-tiered-circuit'.)
The results were poor. There were 5 places where there could be a light from any of this, but they were way too dim.
Someone, had recently suggested that those 2N2222 transistors could work in reverse.
Wondering if it would help, I took out the transistor in order to turn it around... and nothing changed.
This meant the transistor was not being used therefore not necessary.
I plugged it in reversed just to see, but no, this transistor was not doing anything... so I put it and its base resistor aside.
Then I began to play with the wires and nothing I did seemed to make more than a small change in the lights.
Then, the magic happened. I was moving a wire and it slipped from my pliers and landed wire-down right into a hole on the breadboard... (drumroll)
And, all the lights got bright!!!
Astonished, I looked at this and walked around and drew it and never touched it for 2 weeks.
It was a very complicated circuit and I was confused about what it was.
But it was bright and I felt it was important.
I was alone there. Nobody else wanted to try this. That is ok.
I made some drawings which I posted, but nobody else could figure what was happening either.
Eventually, I read Tesla's lectures and began to see the parallels with my '2-tiered circuit'.
I kept reading the tesla lectures because I gained insights each time I did this.
At one point I changed how I drew the circuit, and made it like a tesla drawing.
From then on the circuit began to make sense to me.
[I also realized that by keeping and teaching the little square dc circuit box and making a ~ to designate that it is ac was a way to stifle our understanding of the way ac works.]
My research continues, and I am thrilled to have your company.
Everyone is welcome to join.
So, I can say that if you were to add an inductor to your big secondary, in series, it would stabilize it, so that it would not interfere with the 10 turn one.
In my little xtree circuit I used a 1.36mH inductor, and I assume you will need a higher H value inductor to do this with yours. (maybe even 5-7H)
I am thinking, just to be on the same page as you, I will make one with the same turns.
I like that rheostat, but I forgot to ask for one the other day at radioshack.
I have a couple of questions about the cfl.
Was that a new one?
Do you think it matters new or old? I am assuming you modified it the way Imhotep instructed.
Twist the 2 little fibers together and connect one twisted set to each side of the secondary?
Last edited by jeanna : 11-20-2009 at 08:50 PM.
Well said. I think one thing that is attracting many of us to these
circuits is that we are all so familiar to DC ... and digital electronics ...
that AC looks absolutely like magic .. and does the strangest things.
Re: Joule Thief/oscillator Innovating...
There are a ton of little transistor amplifier/oscillator circuits
that could stand a new fresh look with respect to
these sorts of low power/self-oscillation ideas.
A common-base approach provides an amplifier that
keeps the waveform completely in phase. So if you want
a 360 phase feedback path, you could use two transformers --
one to 180 it ... a 2nd to 180 it again ... and then fed back.
By using coils here ... you can get coil gains in voltage or current
... and the trick would be to power the transistor w/o batteries ..
if the coils can be stimulated from antenna.
JT is common-emitter. The phase is shifted thru transistor - 180 ...
but the transistor can have a gain .. and depending upon
the transistor you pick .. you can exploit that gain to "amplify".
So transistor selection requires a bit deeper thinking ... if
we want really really low power here.
common-collector is for impedance matching ... and so doing it this
way might give you finer control with your coils/transformers.
I was also looking at so called "power amplifiers" ... which
at a minimum utilize 4 transistors: 2 PNP, 2 NPN .. of similar
characteristics ... and do a PUSH-PULL.
Put one of these push-pull power amps into feedback oscillation,
and you might be able to tap out WAY more power.
There are so called "feedback" amplifier .. that with a slight
change ... could be brought into permanent feedback intentionally.
Next folks could go the op-amp route ... where much of the
tricky amplifier circuitry is already nicely put in a chip for you.
Making these oscillate is pretty easy ... and they can be pretty
low power. I have yet to see a Joule Thief-like device with
an op-amp. Any op-amp gurus want try that?
Realize that many here are claiming that their transistors barely
get hot ... and all the high voltages are in the coils, etc.
So an op-amp, which just has transistors inside it ... probably
can be tricked into working just fine in a JT ... reducing complexity
and part count ... making it easier for folks to replicate.
A digital flip-flop might be a digital electronics approach --
And for the old school ... or really intense engineers,
how about a vacuum tube Joule Thief oscillator? That would so cool
and you could warm your hands by it.
Jeanna, Tec, and Morpher
This is all very interesting and worth pursuing. Jeanna---Your story about the wire falling into the hole and lighting things up bright was great. I look forward to the work ahead on this circuit. Tec---I have a bunch of those little tiny toroid coils and understand what you are doing.
Morpher---- What you are talking about is something that has been bugging me for months. There are lots and lots of simple oscillator circuits out there that we could look at to see if maybe one could be tweaked and twisted into whatever we wanted. We could perhaps take an existing design, change things a bit, and make it into a super JT. Make it light up a ball park--- on one AA?
I have been using a 10/$1 one half inch OD toroid from allelectronics Tor-23
It is a bit less than the diameter of a AA and with care and thin mag wire for all the wires, I think this should fit inside the AA slot of a battery holder with room for all the rest of the parts of a small JTC
I just got 175volts from one of these the other day. It lit a neon and has room for many more turns.
I am glad you liked my story, thanks.
I was studying those wonderful physics lectures from prof Lewin at mit last summer, and according to what he said, this very big and powerful but short toroid should be able to make a much more powerful circuit if 2 (or 3 ) were stacked and then wound together as one.
It seems to be a function of the area of the shape defined by the wire. The shape of the 'surface' that the magnetic flux passes through looks like a spiral staircase when you coil the wire, but this helps me to see why my thicker toroid called the filter is the best one I have.
I have been purposely working tiny but I am sure the increase is exponential.
should battery be protected with diode in JT?
so that a humble 1.5V white LED looks like a blinding SUN!!!
Tonight I decided to go a bit more power ... switching to 12V input --
and using a TIP31 transistor. With the auto ignition coil I'm using
on the other side of the JT, I managed to shock myself quite
nicely 3 or 4 times tonight.
TIP31 gets nice and toasty! CFLs light up very nicely.
With 6V input power, I found that putting very strong NEO magnets
near my transformer, I could tune and alter the frequency and power
levels. So yes this is a self oscillating circuit ... but it can be
very easily controlled, frequency wise, using a strong magnet
near your transformer.
My little transistor was getting too hot when I was playing
with transformer-magnet ... so I had to switch to TIP31.
One thing I find a bit weird is that when the magnet approaches
the transformer coil in JT, there is a noticeable audio tone,
and I see current go way UP from input battery ... yet
the battery is really getting AC all over it and so the meter
may in fact be reading incorrect DC current.
So this circuit is a bit misleading if you attempt to measure
DC current (or DC voltage) from the input battery.
The battery is not protected from the back EMF using a diode.
I tried to do that .. and found the battery drains just a bit faster ...
probably because diodes aren't perfect. So I'm torn
whether or not a diode should be used to protect the battery.
Perhaps someone more skilled in electronics could chime
in with an opinion.
Last edited by morpher44 : 11-21-2009 at 06:12 AM.
The Lewin stuff is great. I wish I had him when I went to college.
The physics teacher I had was more of a math teacher ...and just
wanted to do math all the time ... never getting the kids excited
with experimentation. In highschool, though, I had a Lewin-like
Earth Science professor who was amazing. A good teacher
can really bring out the best in you.
The stacked toroid idea sounds good.
I would recommend larger gauge wire though.
You would be surprised how much resistance is in that tiny
mag wire. You want to keep resistance down to an absolute
minimum if possible.
In my humble little JT/Aircoil experiments I'm amazed at the
distance inductive coupling can occur. The toroid KEEPs
the magnetic field locked in the toroid ferro material ... w/o
a chance to poke out and interact with the surrounding area.
This may be ideal for a transformer to reduce losses ...
because you cage up the magnetic fields and don't let them
"move" things out side.
But ... I'm thinking really we shouldn't think of the
bifilar toroid coil as a transformer in the JT. I'm thinking
really we have the transistor BASE side ... which is your
feedback coil -- like a tickler coil in the armstrong oscillator --
and we have the DRIVE coil ... which can have a super-duper
high voltage on it since the current is impeded.
The so called base tickler coil can be quite humble.
Also, if the transistor is one that can produce a large gain,
within its operating parameters -- picking the base resistor
to place you right in the middle of the linear current gain slope --
the tickler coils feedback to the base can be a very minimal
current. By winding it with a minimalistic number of turns,
just enough for that feedback --- and with a transistor
that has large gain -- the drive coil can be more BEEFY.
The next consideration, though, is whether you want
that drive coil to have its magnetic field locked up and
contained -- ala toroid -- or if you want it to BURST
out all over the room -- ala Dr. Stiffler ... OR do
you want that drive coil to be a primary to yet another
larger -- more turn -- secondary ala Tesla.
Or ... a less turn secondary so that you can have
high current, low voltage output. This would be the way
to go to run little motors say.
So for the JT circuit, I'm thinking that you can pick
your transistor and your coils so that they play well together --
depending upon what your trying to achieve.
I like all the LEDs light ... but I'm SHOCKED at how
expensive those super brite white LEDs are.
The price for these is too high.
CFLs, on the other hand, are getting real cheap.
There are sales ... and sometimes you can buy them for
as low as $1.00 USD.
Further, CFLs can be very very bright ... at the right frequency.
So a nice low cost lighting system would use CFLs.
I am floored that you can light a CFL with 1.5V.
But on the other hand, I am aware that coils and capacitors
can bring voltages up very high at resonance -- depending upon
Q. So you want Q very high ... inductances very high.
One light bulb that went off in my head re: the Hendershot material
is that he simply is wiring several inductors in series ... winding all
over his circuit ... to create a very large inductance.
So this approach of chaining several inductors down a network
of little tuned nodal areas -- ala Eric Dollard's analog computer approach ---
shows some real promise.
One thing that holds everyone up in that regard is they
want to do circuit analysis.
But I think Jeanna intuitive approach of plugging things in various
ways to see what works ... is the same approach I'm using ...
and is the same approach many inventors of the 18th/19th/early
20th century. I think what we LOST ... in the later 20th century
is that ... "lets just try things" attitude for invention. We got
all bogged down in the theory ... and equations ... and
lost the fun of experimentation. As you read the biographies
of various inventors, though, you find that they didn't
know theory ... they just used intuition ... and figured out
theory LATER -- or had to find those who could help them
I am using it only as a source of pulses.
So, the gain is irrelevant and the fact that the mag field stays mostly inside is helpful to loop and re-loop and switch back with every re-loop.
In the primary bifilar, which is center-tapped, there is a switching of the direction of the mag field inside the toroid. So the frequency of pulses can be regulated by the resistor at the base of the transistor. The higher the resistance, the higer the frequency..(and the voltage goes down as the frequency goes up.)
It helps when you pop them cuz the voltage spikes get too high.
I am very encouraged by lidmotor's replication and the ease he had in getting it to turn on and even that he can use that rheostat that lowers the voltage...I am wondering about the 2N3055. I have a lot of trouble with those things and I just bought 1 TIP3055 which is what lidmotor used, and what xee2 always uses. xee2 had earlier success than I did (but with a smaller fluoro tube.)
I was pleased to see Eric's video. I became more confident in my intuition that it was the series part and not the transformer part that adds so much to this already pulsing system.
AND I have not yet managed to set anything up exactly like his with a cap crossing between the lines, but I want to try it.
[edit... I may have, and I don't realize it. I better study my drawings some more.]
Also, please let me repeat this.
If these things can be tested and shown at 1.2v, then increasing the output is easy.
If 1 cfl can light with 1.2v and you use 12 volts... I know it will not increase by 10 with all the components being the same, but I am guessing that the thicker version of this very big toroid will be able to supply much higher volts to the pulses... to be shown...
and silently, please think how obnoxious those sparks are. Imagine not being able to turn that off ever... not for me!
So morpher44... you in?
I need to start winding some toroids.
Last edited by jeanna : 11-21-2009 at 08:13 PM.
Charging a 12v SLA off the light
@ Jeanna & All
I got somewhat side tracked today replicating an idea that Mart Hale came up with for the one magnet no bearing Bedini. I posted a video of it over there on that thread if any one is interested. I did have some time to try something with the light today and it worked. On my 10 turn winding I put a bridge rectifier and charged up a small 12 volt SLA while the CFL was running. For some reason I am getting very high voltage at that point if I turn the rheostat up. To set the voltage right for charging I used a big cap and turned the dial up just enough to get the light on and have the cap sitting at 20 volts (on full brightnesss the voltage was up over 100 ). I let the system run for about an hour and it charged up my small 12v SLA just fine. I'm really not sure why that 1.2volt AA can do all this. There is some weird stuff going on in that big toroid.
It is the reason I was never stressed about proving ou n stuff like that.
It's in our hip pockets.
It's been there all along
Last edited by jeanna : 11-22-2009 at 04:59 AM.
I've never wrapped one of these before? Does it matter which direction you make each wrap. And how crutial are the amount of turns. What if your off by 1 or 2 turns on the primarys.
I threw one together and can light up 2 of the new led 1.2 watt bulbs in pararell. I only had a 25ohm resistor need to get a 22. Its been running for 5 hours on a C cell batttery now. Still going with running volts at .974.
The led bulbs I'm using are unmoddified and still have the circuit boards and all inside.
The true answer is there is only one way to know and that is to try it.
Each toroid is different and so is each transistor.
These 2 elements can determine how many turns of the primary wires you need to make.
The 22 or 25 ohm value of the resistors comes directly from the mix of the 2 elements.
What you must have is the end of one wire connect to the beginning of the other.
It is a center tapped primary, and it is often the case that it is off center.
But for your first one, just do it and see.
makezine has an excellent youtube video on it
Are you referring to the lights of america 19 leds bulb?
2 in series.
Any led that is intended to be used in a wall socket is heavily protected from surges. They have to be.
[The overvoltage that will do a led in is so little and the wall surges are frequently more than 10 times too much.]
This means that if you didn't modify it, you are doing well.
Mine have caps and I think supercaps because when the power goes off, the light lingers for 20 seconds or so.
This weekend I did want to focus more on the Joule Thief.
I looked around online -- briefly -- for a big ole toroid .. but
the ones I found cost a little too much for my budget.
Meanwhile, one of your comments reminded me that I needed
to use a variable resistor to the base of the transistor for
tuning purposes. Doh! I kept trying to just "get lucky" w/o
building in a way to tune.
Anyway, thanks for that. I had a variable resistor on there
a few months back ... but somehow forgot to do it again.
I made a video here proposing a simple circuit that some
might want to replicate ... if they are lazy like me and don't
want to wind a 240 plus turn coil. I've been winding all these
coils and I'm getting blisters.
YouTube - Joule Thief Circuit - Driving CFLs with 1.5v
I went to the TIP31 ... because I had a bunch of them and
because I wanted to experiment with higher voltages and currents.
On advantage to higher voltages here ... is that with those
ferro coils, you can get them way up in voltage ... and
your little transistor needs to be able to handle that.
Yes 2n3055 is good too ... although harder to plug in proto board.
I probably should have a big toroid in my arsenal. Searching!!!
Another thought I had was that "if" we could get the Joule Thief
to produce "exactly" 60 Hz (or 50Hz depending upon location),
then folks could experiment with driving traditional appliances
too. I.e. design the electronics to self-tune to exactly those
frequencies ... and have that be the design goal for resonance.
I found that my CFLs were happy, though, at about 278Hz.
One more discovery to pass along.
If I put my ammeter in the mix, its difficult to impossible to tune
and make the CFLs light. The circuitry in the ammeter alter
the situation to an unusable condition. Hence, measuring
current might be best done with an old fashioned analog ammeter.
So I switched to an analog ammeter and see I'm using about 400milliamps
or just under .6 watts with light that I would describe as "good enough
to read by". Interestingly if you change from 2 CFLs in series to 1 CFL,
the amp draw doesn't really change .. only the brightness of the light.
D cells have a typical capacity of 20500 mAh ... so this should run
for almost 51 hours from a fresh battery ... probably less since
some threshold will be reached whereby the JT will no longer
Last edited by morpher44 : 11-22-2009 at 05:50 AM.