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Author Topic: Smoothest, and best, store purchased Joule Thief I have seen yet.  (Read 40142 times)

MileHigh

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #30 on: October 17, 2013, 07:23:59 AM »
A crystal oscillator like TK is showing was the standard workhorse for clocking computer boards and other boards for years.  Now some of those parts literally look like specks of pepper.

Anybody hear of Fox?

http://www.foxonline.com/

Just name your frequency and your package.

Legalizeshemp420

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #31 on: October 17, 2013, 07:52:40 AM »
A crystal oscillator like TK is showing was the standard workhorse for clocking computer boards and other boards for years.  Now some of those parts literally look like specks of pepper.

Anybody hear of Fox?

http://www.foxonline.com/

Just name your frequency and your package.
First thing I hit was Oscillators - Through Hole and most of them have now been discontinued. :(

TinselKoala

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #32 on: October 17, 2013, 07:32:41 PM »
Check Ebay, these things are all over the surplus market, in many many frequency choices.

I also have about 20 of these little amplifiers:
MC1590G


Legalizeshemp420

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #33 on: October 17, 2013, 09:07:56 PM »
Damn, an all in one small package amplifier and AGC in one.  What is the noise on that?

TinselKoala

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #34 on: October 18, 2013, 12:33:12 AM »
I dunno, the most I've done is to breadboard one up and confirm that I can put a signal in and get a signal out. I can't even get near their frequency limit though, especially without putting it on a good PCB.  At present I have no real use for them. They are brand new, still on their little plastic carrier things to keep the pins straight. The friend who gave them to me was a technician at a local company that made MRI machines but went out of business years ago, and these are new old stock from there.

e2matrix

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #35 on: October 18, 2013, 01:08:45 AM »
Are solar charging lights really a Joule thief?   Or are they just good efficient solar battery chargers and LED circuit?   I guess you could call them a JT if you want but I always thought of a JT as having a bifilar wound toroid or at least a bifilar coil and I doubt these have bifilar coils in them.   Just a regular inductor.    But it's nice that they are getting so cheap thanks to mass production (and of course China).   

Legalizeshemp420

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #36 on: October 18, 2013, 01:31:51 AM »
Are solar charging lights really a Joule thief?   Or are they just good efficient solar battery chargers and LED circuit?   I guess you could call them a JT if you want but I always thought of a JT as having a bifilar wound toroid or at least a bifilar coil and I doubt these have bifilar coils in them.   Just a regular inductor.    But it's nice that they are getting so cheap thanks to mass production (and of course China).
A Joule Thief is just a cutesy name for a blocking oscillator circuit anyway and if you look up some schematics for blocking oscillators most hardly use a bifilar coil if at all.  JT (Blocking Oscillators) have been around for longer than you are old but only in 1999 did some fool call one a Joule Thief.  I hate the term but it is what the modern people know it as so stuck using it.

Pirate88179

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #37 on: October 18, 2013, 02:34:18 AM »
A Joule Thief is just a cutesy name for a blocking oscillator circuit anyway and if you look up some schematics for blocking oscillators most hardly use a bifilar coil if at all.  JT (Blocking Oscillators) have been around for longer than you are old but only in 1999 did some fool call one a Joule Thief.  I hate the term but it is what the modern people know it as so stuck using it.

That's my understanding as well.  A fellow in England named Big Clive coined this term and it has been used on youtube and elsewhere online ever since.  A little further research shows the circuit was developed by a Russian in the 60's.  (I forget his name)

I "thought" I knew a lot about these circuits and then I come to this topic and learn of the existence of radial inductors and a tiny blob covered chip.  This means that I can take one of those chips, a resistor and one of those inductors and have a JT circuit that will have a footprint the size of a dime.  Now I am wondering why I wound all of those 1" toroids all those years ago!!!!  Of course, this is for a low voltage JT.  I am still working on my circuit board high voltage JT.  (Similar to the modified flash circuits)

Can you put enough of those radial inductors in series (or parallel?) to output 400 volts from 1.5 volts in a blocking oscillator step up transformer (JT) type device?  That would be really cool.

Bill

Legalizeshemp420

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #38 on: October 18, 2013, 03:41:19 AM »
You can easily step up the voltage but the current is another story.

Pirate88179

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #39 on: October 18, 2013, 03:50:30 AM »
All of the led bulbs and modules that I use in my lights respond very well to high freq./high voltage and very low current.  That is why I stick to 1.5 volts or "dead" batteries for the input.  I light my apartment for free using the dead batteries given to me by my friends.  350-600 volts seems to work well.  About 200 mA draw usually.

I feel so stupid.  I had no idea those type of chips were available.  Oh well, I love to learn.

Bill

Legalizeshemp420

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #40 on: October 18, 2013, 03:53:08 AM »
With a JT you can easily get over 1500 volts but I will be damned if I know how to even measure that as everything I have would die (I lost my first DMM due to negative ion generators I used to make).

MileHigh

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #41 on: October 18, 2013, 04:48:17 AM »
You can make an indirect measurement for the peak voltage.  You swap the LED for a low value resistor, say 20 ohms, and look at the peak voltage across the resistor.  That tells you the initial current.  Once you know the initial current then you implicitly know the peak voltage for any resistive load.  What ultimately puts a limit on how high the voltage can go is the parasitic capacitance associated with any high-resistance load and the amount of energy the inductor has available to discharge into the parasitic capacitance.

In plain English, if you see a 7 volt peak when you use a 20-ohm resistor as a load, then if you use a 500-ohm resistor, you will scope a 175-volt peak that is narrower.  You know what the peak voltage is expected to be before you scope it.

MileHigh

TinselKoala

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #42 on: October 18, 2013, 07:50:33 AM »
Hey Bill, I just posted a video of a quick test of the "Pirate Light"!
 
http://www.youtube.com/watch?v=f81ZEB_zGVA

 8) (Need shades, the light is so bright!)

Pirate88179

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Re: Smoothest, and best, store purchased Joule Thief I have seen yet.
« Reply #43 on: October 18, 2013, 04:18:12 PM »
Very cool.  I see you got bit by the circuit already, ha ha.  I usually cover the HV outputs with hot glue for insulation but I thought you might want to solder something different someday so I left them bare.  I still get zapped by these even though I am mostly careful, ha ha.

Bill