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Author Topic: Acme Fixer's highly efficient Joule Thief help needed.  (Read 36001 times)

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #15 on: October 12, 2013, 12:39:39 AM »
I know what I meant was I don't have a way to constantly poke it since I can't freeze a capture like I could in a DSO.
Ah, you have no signal generator, I take it. Well, your scope does have a single-shot trigger mode, and you do have a camera....
So rest the camera on something steady, set the scope to single-shot, open the shutter, poke the tank with a wire to get a ringdown, then close the camera shutter. You'll have what the designers of the first digital scope had to use: a photograph of a single sweep on an analog scope.

Or you could build a simple 555 squarewave pulse generator in half an hour, and use that.

Or, you could use a 30-dollar Arduino and make your own selfcontained inductance meter that does its own poking and measuring. I see that Radio Shack is now stocking Arduino! Or you can order them for half that price from Singapore or China if you want to wait a couple of weeks.

Legalizeshemp420

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #16 on: October 12, 2013, 12:44:08 AM »
Ah, you have no signal generator, I take it. Well, your scope does have a single-shot trigger mode, and you do have a camera....
So rest the camera on something steady, set the scope to single-shot, open the shutter, poke the tank with a wire to get a ringdown, then close the camera shutter. You'll have what the designers of the first digital scope had to use: a photograph of a single sweep on an analog scope.

Or you could build a simple 555 squarewave pulse generator in half an hour, and use that.
Well, I do have an ancient 555 around here I found in my antiquated parts pile (what was left after the stupid Oct 28, 2006 flood/fire).  Most of my parts date from 1985-1992 and my cans of old IC's I miss the most but something had to go to make room years ago after the fire so I tossed them.  About 50 dollars worth so not that great of a loss but a lot were ceramic.

Now if only I could manage to have been allowed to keep those Germanium trans I had but no go as I never got those back after the cleanup that took 3 months from hell.

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #17 on: October 12, 2013, 12:50:39 AM »
Hmm... OK, I have 14+14 turns of # 27 with short leadin wires to my little toroid, and each winding measures right about 400 microHenry. But the one on the schematic says 38 microHenry. I wonder if there is another decimal point issue here.

Legalizeshemp420

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #18 on: October 12, 2013, 12:51:55 AM »
He says he uses a really high perm toroid so less winding for a greater inductance but 38uH is awfully low.

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #19 on: October 12, 2013, 02:52:14 AM »
Well, I dunno. I just got this one running, by taking off more and more wire from my toroid, it finally started oscillating. Now it only has 7+7 turns on the toroid, and it still measures 85 microHenry or so. But my frequency isn't anywhere near as high as yours. I'll take off a couple more turns in a few minutes, need to eat some supper first.

I built it onto a clothespin so I could grasp a battery easier. Here it is running brightly on a AG1/LR621 button cell. I'm using the exact cap values as in the schematic and a BC337-25 transistor, a 3/8" toroid from a CFL....



TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #20 on: October 12, 2013, 03:52:46 AM »
OK, I just looked at your video again, and based on my findings and your toroid, I think you have _way_ too much inductance, just like I had at first. 

Pirate88179

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #21 on: October 12, 2013, 04:52:18 AM »
TK:

I am pretty sure you know this already but, those toroids from CFL's are powdered iron and not ferrite hence the low permeability.  They still work as you have seen but, you have to play around with them. (I don't like them at all)  Of course, they did do the job they were engineered to do in the first place but hey, can't these people design electronics with better components that we can salvage?  I mean, come on, we need good stuff, ha ha.

Bill

Legalizeshemp420

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #22 on: October 12, 2013, 05:59:49 AM »
TK:

I am pretty sure you know this already but, those toroids from CFL's are powdered iron and not ferrite hence the low permeability.  They still work as you have seen but, you have to play around with them. (I don't like them at all)  Of course, they did do the job they were engineered to do in the first place but hey, can't these people design electronics with better components that we can salvage?  I mean, come on, we need good stuff, ha ha.

Bill
Yes, my magnet sucks right to them and they are pretty heavy for their sizes.  Since the shipping on toroids is more than the price of the toroid I use what I can salvage.  I bought the one in the video as well as a surprise pack (both from Elec. Goldmine) and they are all iron which is a bummer. :(

btw, when I just used my toroid I wound with 28ga 2 turns on a toroid from a CFL my frequency went way up.  It was up so much I could no longer zoom in to see what frequency it went to.

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #23 on: October 12, 2013, 01:15:17 PM »
Heh.... Well, I left mine running on the tiny AG1 cell, from the time I took that picture above until a few minutes ago, and the light was out. I took off the toroid and took some wire off it. With 5 turns remaining on the toroid I get about 45 microHenry on the meter. If I go to 4 turns I get less than the spec of 38 uH, so I went with the 5 turns.

Now... I put the same AG1 cell back in... and it lights up, but doesn't run very long. Then it shuts off.... and in a few seconds, lights up again, dims, shuts off... and repeats. IOW it seems to be doing the same thing that the DALM thing is doing (yes it's still doing it, but much longer between osc bursts, still on same battery) but with light in the LED. I made a little video showing the cycling, it will be processed and up for viewing shortly. I haven't scoped this version yet to see if the spikes are narrower than they were before when I had too much inductance.


http://www.youtube.com/watch?v=mTOuUMsivWA


Legalizeshemp420

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #24 on: October 12, 2013, 02:32:33 PM »
For my purposes this will not work since it will not even operate much above 20-30ma whereas the DALM will.

How 'Super Efficient' is this?

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #25 on: October 12, 2013, 05:08:21 PM »
I dunno, I'm not the one making the claim. My build doesn't seem all that "super efficient" to me, but it is running on batteries that won't run (to light) some of my other JTs.
I like the "gasping for power" effect though.

MileHigh has shown how to make an easy analog power measurement computer out of a single TL082 dual opamp chip costing under a dollar, with a few resistors and a capacitor, that produces an output that can be read on an ordinary DMM to give power. I don't know if it will work on a JT signal but I'm going to give it a try, later on. I also have my light intensity meter using Arduino that I can use to measure the light output of its "standard" white LED. I'm not sure how accurate this is when looking at a pulsed light source, but I will be finding out.

Legalizeshemp420

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #26 on: October 12, 2013, 05:20:13 PM »
I found a way to test for inductance but I need a sine wave source of 1hz to 2mhz that is super easy but I must be able to manually sweep it.

Btw, on this BK2120 it came set for 110Vac but has 110vac/120vac/220vac/240ac.  I haven't ever, in 30 years of probing the AC outlets with a meter, seen 110vac unless something was wrong it was always 120-122vac.  Should I leave it at 110vac or switch it to 120vac?

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #27 on: October 12, 2013, 06:03:29 PM »
OK, I've at least measured the battery voltage during the gasping performance.

This one needs around 715 mV to turn on, and turns off at around 635 mV. This is higher by about a tenth of a volt than the performance of the DALM.

TinselKoala

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #28 on: October 12, 2013, 06:21:02 PM »
I found a way to test for inductance but I need a sine wave source of 1hz to 2mhz that is super easy but I must be able to manually sweep it.

Btw, on this BK2120 it came set for 110Vac but has 110vac/120vac/220vac/240ac.  I haven't ever, in 30 years of probing the AC outlets with a meter, seen 110vac unless something was wrong it was always 120-122vac.  Should I leave it at 110vac or switch it to 120vac?
I'd move it over to the 120 VAC setting. It probably won't make any difference. If you were in Japan you would be better off using the 110 position.

You really really do need a signal generator. I have one of these and there is nothing wrong with it for the purpose you need.
http://www.ebay.com/itm/1MHz-Function-Generator-Elenco-FG-500K-Kit-Waveform-/331042803024

For your inductance measurement you will be sweeping a tank circuit and looking for resonance, so you just need to change the value of the capacitor in your tank in order to get the resonance frequency into the range of your instrumentation.

If you are setting up an electronics workbench you might like to budget for something a bit better. This looks really cool to me, I wish I could afford one right now.
http://www.ebay.com/itm/AE20125-10-MHz-Sweep-DDS-Function-Generator-Kit-with-USB-and-Modulation-/251169054479?pt=LH_DefaultDomain_0&hash=item3a7ad79f0f

Or, for a little less, you can get an Arduino and learn how to use it. They are amazing critters, very useful for all kinds of things.
http://www.youtube.com/watch?v=S6N8ys8FiA4

Legalizeshemp420

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Re: Acme Fixer's highly efficient Joule Thief help needed.
« Reply #29 on: October 12, 2013, 06:21:53 PM »
DALM is a better circuit from my testing here as well.  I am not sure what AcmeFixer was on about and I can't tell either since he has not appeared on this thread YET his name, and circuit, was mentioned in the title of this thread.

I guess we can safely say it is pretty much rubbish and if you notice he supposedly made it even better in the second version but it did get more complicated as well.  I have my suspicions about that circuit as well.

Well, time to stop what I am doing until I can measure inductance. :(