Big Joule Theif

[slayer007]

I was thinking about making a fox hole radio.
And replace the head set with a rectifier and see if I could get enought voltage to run a JT.

Here is a link that shows how to build one.

Foxhole radio - Bizarre Labs

[StevanC]

newbie on track

I did make an lousy JT off a toroid I salvaged from a dead PC PSU...

I didn't realize the internals and difference among the JT and Bedini's Solid state energizer ("SSG") back then...

It was only after I found out that the JT starts with the BJT shorted ("ON state") instead of the Bedini's SSE that depends on the initial spike or will just 'lay around dead' for it starts with the BJT wide open ("OFF state") and depends on the initial inductive 'sparkie' (hard switch vs. slow rise)

Once that was clear, the JT could "come to life" :-)

So my both off spec toroids are NOW working:

1. I blew a bunch of diodes the fist day off one 1.2 and two in serises NiCd akkus :-(

2. I almost lit a flash bulb (cam-flash kind of bulb) - was all bluish - killed the TIP31C too ...

3. I ended up with my (only left) 2x green LED in series over that 2N2222 and the 'backend' winding (120 turns approx) free

And i tried:

I hooked up a 200V330uF capacitor off a 1N4007 diode

4. it charged up to about 8V and more depending on the powering cell

I picked a SCR (BT151 was at hand: TO-220 case) and made him triggered by a LED (an red LED) and put the 'middle leg' on the positive of the capacitor and then let the lateral leg (which would be a 'emitter' if we consider a transitor) to some load...
It just so happens that I can connect it back to the powering battery... as they can share the common negative (the backend is 'floating' anyway)

So I connect back,
5. The capacitor 'hangs' about 3.8V now (2.4V across the SCR) as the battery slowly declines from 1.31V down to 0.7 where the LEDs stop to shine...

there is place for improvement:

A. a FWBR of shottky diodes: A FWBR introduces 2x Diode forward volt-drop, so shottky keep it about 0.4...0.6V
B. All white LEDs for both 2N2222 and the trigger (would rise the capacitor up to 4.2 or so...)
C. how do i introduce a permanent magnet to a toroid?

interesting?

[Lidmotor]

Foxhole radio

I was thinking about making a fox hole radio.
And replace the head set with a rectifier and see if I could get enought voltage to run a JT.

Here is a link that shows how to build one.

Foxhole radio - Bizarre Labs

Thanks for the link to the "Foxhole radio".
Wow! That takes me back in time aways. I built a crystal radio as one of my first electronics projects a long long time ago. A "cat's whisker" radio--I still remember it.. My grandmother used one at her bed at night to listen to talk radio shows before she went to sleep eack night. She liked it because it never had a dead battery and it always worked. I don't think that one would gather enough energy to run a joule thief though. I went to Ebay to see if you could still buy one and stumbled upon this guy that sell the razor blade part of the "foxhole" design. Scroll down the page and you will see the simple circuit for the radio. Notice the "Earth ground". Hummmm. What is old is new again???

Gillette Blue Blade Crystal Radio Detector Kit - eBay (item 310120243506 end time Mar-04-09 20:45:32 PST)

Lidmotor

[slayer007]

Thanks for the link to the "Foxhole radio".
Wow! That takes me back in time aways. I built a crystal radio as one of my first electronics projects a long long time ago. A "cat's whisker" radio--I still remember it.. My grandmother used one at her bed at night to listen to talk radio shows before she went to sleep eack night. She liked it because it never had a dead battery and it always worked. I don't think that one would gather enough energy to run a joule thief though. I went to Ebay to see if you could still buy one and stumbled upon this guy that sell the razor blade part of the "foxhole" design. Scroll down the page and you will see the simple circuit for the radio. Notice the "Earth ground". Hummmm. What is old is new again???

Gillette Blue Blade Crystal Radio Detector Kit - eBay (item 310120243506 end time Mar-04-09 20:45:32 PST)

Lidmotor

Thanks Lidmotor

It still looks like a fun project to try.
I wound a coil all ready I just have to run out and buy some razors.
I seen some where were you have to burn them first with a torch to get it to work all so.

I tried it with a blade from a box cuter but it didn't work.
I think it was to thick of a blade.

[Bodkins]

Earth Ground and more

[StevanC]

@all:

Anyone tried to loop back the tertiary wind with a fwbr so the RE spike hits the running battery?
8:-)

A NiCd akku should be indestructible?

[redeagle]

@all:

Anyone tried to loop back the tertiary wind with a fwbr so the RE spike hits the running battery?
8:-)

A NiCd akku should be indestructible?

I've done that with my bedini. If you do it make sure that you have a cap across the primary. And no battery is indestructible. Draw it too low or hit it with too high of a voltage and poof it's gone.

[StevanC]

I've done that with my bedini. If you do it make sure that you have a cap across the primary. And no battery is indestructible. Draw it too low or hit it with too high of a voltage and poof it's gone.

according to Bedini (and he seems to be right?) the capacitor kills the radiant.

If we want to put "positive" energy to the primary (powering battery) we should "capture and dump" - with a CiS and a switch (SCR+neon, SCR+diode, BJT+555,...)

And if those _current_ spikes off the capacitor might kill any battery (seen that)...

But how does the NiCd chem. handle the RE compared to lead-acid?

I'm about to try to find out...
;-)

[Lidmotor]

555 timer pulsed JT circuit----Kubikop's great idea

I put a 555 timer on Slayer's 2" toroid flourescent bulb circuit and it worked. This is what Paul (Kubikop) has been working hard on and I had to try it----Pulse the JT and only run it part of the time to save power. He figured that 60 to 100Htz would do it and it did. Your eye can't tell that the power is being turned off part of the time. It is a circuit within a circuit. Paul has done all the research on this and the credit for it is his. Tests need to be done to get it dialed in right but here is the idea:

YouTube - Kubikop's 555 timer pulsed Joule Thief light

Lidmotor

[slayer007]

@Lidmotor

Thats a very good idea save more on power.

I was thinking some thing like that but using another JT.

Very Nice Lidmotor & Kubikop

[StevanC]

I put a 555 timer on Slayer's 2" toroid flourescent bulb circuit and it worked. This is what Paul (Kubikop) has been working hard on and I had to try it----Pulse the JT and only run it part of the time to save power. He figured that 60 to 100Htz would do it and it did. Your eye can't tell that the power is being turned off part of the time. It is a circuit within a circuit. Paul has done all the research on this and the credit for it is his. Tests need to be done to get it dialed in right but here is the idea:

YouTube - Kubikop's 555 timer pulsed Joule Thief light

Lidmotor

Care has to be taken for the 555 to pay off:

If the 555 is using more power than the save for the lesser duty cycle is...

So, my guess is 30% or less on time?

my LED JT draws 50 mA with full recovery on only 3 LEDs?
witout recovery whole 150mA

And no mention of a 555 in sight?

That makes a 555 can draw 50mA max to be of any use?

its a narrow path there IMHO?

Today i will fire up (hopefully) my 1st HV JT

can't wait

[Xenomorph]

Power consumption considerations

@StevanC:
Don`t forget that the strength of this circuit is its energy recovery possibilities.

He could try to run the 555 off a supercap charged up by his peltier or BEMF during operation, then the 555 power consumption does not matter.

I am using 555s for Joule thief circuits that have a very Low Power Consumption
1 mW Typ at VDD = 5 V and Single-Supply Operation From 2 V to 15 V
If anyone cares (maybe Lidmotor), it`s Texas Instruments Model TLC555 (NOT NE 555 !)
We are talking about an IDD Supply current of 250 MICRO-Amps (!).
The peltier might be able to reach that current value alone.

Great finding Lidmotor and thanks to Slayer007 for the basic circuit !

[Jesus M NIeves Oliveras]

I put a 555 timer on Slayer's 2" toroid flourescent bulb circuit and it worked. This is what Paul (Kubikop) has been working hard on and I had to try it----Pulse the JT and only run it part of the time to save power. He figured that 60 to 100Htz would do it and it did. Your eye can't tell that the power is being turned off part of the time. It is a circuit within a circuit. Paul has done all the research on this and the credit for it is his. Tests need to be done to get it dialed in right but here is the idea:

YouTube - Kubikop's 555 timer pulsed Joule Thief light

Lidmotor

Hi!

Pardon me for interrupting here with my questions.

Can you post the circuit of the replication on the video.
You know. I can read and write english, but when it comes to understand it while spoken, I cant catch it well.

Thanks in advance.

Jesus

[StevanC]

@StevanC:
Don`t forget that the strength of this circuit is its energy recovery possibilities.

He could try to run the 555 off a supercap charged up by his peltier or BEMF during operation, then the 555 power consumption does not matter.

I am using 555s for Joule thief circuits that have a very Low Power Consumption
1 mW Typ at VDD = 5 V and Single-Supply Operation From 2 V to 15 V
If anyone cares (maybe Lidmotor), it`s Texas Instruments Model TLC555 (NOT NE 555 !)
We are talking about an IDD Supply current of 250 MICRO-Amps (!).
The peltier might be able to reach that current value alone.

Great finding Lidmotor and thanks to Slayer007 for the basic circuit !

1. I understand the recovery schema i recovered 66% as i stated earlier?

2. there are caps that simply recover to 0.5V or more each time after a dead-short.

3. That TLC555 sounds 'wow!', beats me how You can use it from AA battery?
form a diode dumped cap (off the 2N2222 or 2N3055?) sure looks promissing to have it @1mW ;-) how much can it source at 1mW - enough to drive a mosfet, but hardly a low RDSon one? (need 4V at least?)


Peltier? yes it could reach it, but at what potential :-)?

[StevanC]

Succesfull replication report:

I made it finally!

~19 turns 0.7mm
~20 turns 0.65mm
~370 turns 0.3 mm

on a PSU ferrite transformer (salvaged)

It runs off a D sized 1.2V accu

I used MPSA06 over a TIP35C (gets warm on work)

I shunted the TIP35C's collector to emitter with a small neon bulb

I shunted the MPSA06's emitter to base with a 1N4448 diode

1K resistor to MPS's base

(+) to common primary & triger

(-) to TIP's emitter leg

and 'buz'

the I soldered a neon light (20cm and 30cm long ones) to the tertiary (370 turn) winding

It shines - the smaller is brighter :-)

it works (!) off a 1.2 battery

the spike on the MPS is about 50V (C-E)

over the TIP its about 80V

and over the neon rod it's about 600V

while drawing (RMS) 537 ... 500 mA off said cell

now to see:
1. how many can we use and maintain this glow?
2. is it more efficient to use LEDs instead neon light?
3. Can we make it more bright and still lower the cost?

Slayer007:

nice project

anyone cares for spice model?