Alright.. So can someone explain to me what each part of a joule thief does? I understand the LED, Resistors and battery
So, in a recent Instructable about a Joule Thief, I was slapped in the face with a gap in my knowledge. I have no idea what the toroid DOES, I know it's an inductor... but is it suppose to transform low voltage to higher voltage? What happens If I wind it more? How about less?
What does the transistor in this setup do?
In a recent Instructable, as I was saying, they did it with only a regular inductor.
I'm in the middle of finals too, my brain feels over used...
What does the transistor in this setup do?
In a recent Instructable, as I was saying, they did it with only a regular inductor.
I'm in the middle of finals too, my brain feels over used...
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The toroid acts like a transformer. The transistor part produces pulsed input, which is enough like AC that the thing works like an AC transformer.
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Anyone have some 'scope traces of the joule-thief circuit, you know like, in time domain. That'd be neat. That would be something I'd like to see.
Wow! That sure is a nice picture. I thank you for sharing, and/or bringing it to my attention.
The basic form is that of a blocking oscillator.
http://en.wikipedia.org/wiki/Blocking_oscillator
I ran across a website a while back that treated it pretty well, but I'm afraid I didn't save the link and can't recall the exact search terms (I just did searches on "joule thief theory", ... simulation, ... circuit, and so forth after reading your request with no success to a depth of 3 pages (sorry, I'm lazy)
The circuit is very basic, so I suppose you could input it into a spice simulator to view the waveforms. It should turn out to be a pair of square-ish waves approximately 180 degrees out of phase, one for the LED and one for the transistor base
http://en.wikipedia.org/wiki/Blocking_oscillator
I ran across a website a while back that treated it pretty well, but I'm afraid I didn't save the link and can't recall the exact search terms (I just did searches on "joule thief theory", ... simulation, ... circuit, and so forth after reading your request with no success to a depth of 3 pages (sorry, I'm lazy)
The circuit is very basic, so I suppose you could input it into a spice simulator to view the waveforms. It should turn out to be a pair of square-ish waves approximately 180 degrees out of phase, one for the LED and one for the transistor base
. Ermmmmm. Your linked-to page is just a more verbose version of what seandogue said. So wot's, uh, the deal?
Mar 13, 2011. 10:20 AMacmefixer
says:
If you clicked on the links I gave in my blog, you would get a more technical explanation. One doesn't even get into the math behind the blocking oscillator. I'll even put in a link to my scope pictures.
. But you, very succinctly, said he was wrong. While his answer may not be in-depth, it is, as far as I can tell, correct.
Careful what you click on. He's a trol and trols usually have an agenda.
I don't think I'll do that. If you don't have the courage to post what you know to this thread, then please just butt out.
Mar 13, 2011. 10:16 AMacmefixer
says:
I could simply copy and paste what I said in the blog. But then I would have to come back here to add/edit it if I decided I made a mistake or want to make changes. Putting what I said in the blog just simply makes sense, and you're welcome to read it. Sorry if you don't agree.
Writing "NO" and then referring to some offsite blog is pathetic and indicative of someone who's a trol. Get a life. I have no patience left for people like you.
Mar 14, 2011. 5:51 AMacmefixer
says:
My adenda is trying to help others here. So thanks for being so appreciative of my helpful answer.
BTW, It's troLL.
BTW, It's troLL.
If that was your intent, you should have posted the content instead of a link to an off-site blog. This site isn't about diverting people to one's own personal site. I find your method of information dissemination suspect, especially since (thank you Nacho) it has been reported that your answer is very similar in substance to what I posted, and you responded to mine by a singular use of "No"
The word was trol when I learned it back in ~1985 or so on Usenet, although it seems to have changed to troll, probably after Al Gore "invented" the internet.
And in my estimation, it fits like a glove.
The word was trol when I learned it back in ~1985 or so on Usenet, although it seems to have changed to troll, probably after Al Gore "invented" the internet.
And in my estimation, it fits like a glove.
Mar 13, 2011. 12:42 AMacmefixer
says:
We know so little about the person asking the question. If I give him or her a highly technical answer, will he just not understand, shake his head, and close the tab on his browser? If I give a simplified explanation, will he misunderstand? Here's a link to my blog with a simplified explanation with links to others that hopefully will help the reader understand.
I have a pic of a waveform of a conventional JT here in my blog.
I have a pic of a waveform of a conventional JT here in my blog.
Nov 20, 2009. 12:35 PMalex-sharetskiy
says:
so the toroid turns into a transformer, when the transistor is off, electricity charges the toroid with a magnetic field, when the field is strong enough, the transistor turns on and convertets the energy stored in a coil into electricity.
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