How to Build a Joule Thief - Step by Step (The simplest switching power supply / inverter)

[@arduinoatolyem2121]

I am writing this review from Turkey. Thanks to this video of yours, I saved 80 batteries, which fell to 1 volt, from wasting. I made a lamp just like you did when you were a kid and used it for reading at night. And without wasting batteries :) I removed the transformer from my broken charger and put it in the circuit. In other words, thanks to your video, I have used 80 batteries in a lamp at almost no cost. Thank you for your beautiful and entertaining explanation.

[@LucasPereiradaSilva]

Your lessons about switching psu's helped me more than months of theory.

[@Brainwulf]

Your aducatiion is the best i see on YT this Devise run and i thank you-my little school english is enough to understand you ---great thanks , und liebe Grüße aus Deutschland/Germany !

[@AThreeDogNight]

Thank you for showing us how to build them with using several different kind of scrap parts, because most channels are always trying to get you to buy something that really was not needed to make them. Thanks, again Tom. PS: I'm from US. & glad that you have gotten this channel, some very informative information you help us with on repairs & such.

[@zx8401ztv]

Simple but a nice way to show a boost converter :-D. Amazing how little parts you can get away with.

[@BillAnt]

For a bit more in depth look, including theory and signal measurements take a peek at (warning this is for DiodeGoneTotallyWild types;) kzbin.info/www/bejne/oKKalKSjedmNesU

[@edgeeffect]

That home-made ferrite core is brilliant... Your Czech DIY culture is stronger than our affluent English alternative!

[@arnislacis9064]

I made this circuit with BC945 transistor & it works so well on dead old battery (0.3v)

[@ab_ab_c]

Best Joule thief video on YT! Thank you.

[@scratchdog2216]

Birds, crickets, and water. Even a dog bark. Nice. Thanx.

[@kabandajamir9844]

The world's best teacher thanks

[@salomejaya7745]

You are my true teacher. Thank you sir....

[@SianaGearz]

Likely a good source of cores: CCFL lamps. I mean they're cheap crap and no longer live particularly long anyway, you might have one that's failing any day now. But it doesn't actually need a particularly good core, a nail or random steel/iron object might suffice.

Thank you for the tip, I was afraid I would have to wait another 3 months before the ferrites from Aliexpress would arrive haha

[@firefox1136]

@ As long as it is a ferrite core you can use anything, you can also use a scrap core like he did. I used a ferrite ring from a small inductor and it works well. It runs at about one kHz and you should make sure, that the core cant vibrate otherwise it makes a one kHz tone.

[@slender1357]

Thanks i made 3 of them and they all worked. Good tutorial

[@pavelbires]

I made 4 of them but only one worked...

[@slender1357]

@zardyあ it was a long time ago, but it was probably bc547.

[@slender1357]

@zardyあ 2n2222 may work, any npn transistor may work

[@staguyaugustin1825]

You are one of the best. You show everything in your videos. I'm trying to see all your videos, because I'd like to know how I can make a bigger reliable joule thief. Thank you so much!

[@zippy777l]

Good one. Modern transformer wire can be soldered direct through the insulation - the varnish is actually a flux - saves the manufacturer's time when soldering transformer coil ends.

[@lvb1b463]

It is so nice that you made this amazing little circuit without soldering.It shows that soldering is not needed for making any small (3 or 4 component circuit).I, myself used solder for even small LED circuits.

[@saiyadadnan6155]

After 20 years 😁😁👏👏👏👏

[@batvanio]

Mmm, this flashlight took me back to my childhood. I had one. Eh, memories, memories.

[@shaikmaqboolbasha4383]

Hello sir excellent teaching and you make this amazing.Thanks

[@makoveliprod]

Аж ностальгия по фонарику, был такой же лет 10 назад

[@stephanc7192]

Great video! Just a reminder. This is NOT for rechargeable batteries. The high depth of discharge will damage a rechargeable battery. Kind regards

[@qwertykeyboard5901]

Rechargeables will work fine

[@stephanc7192]

@@qwertykeyboard5901 They will. But you will kill them

[@Tracks777]

Lovely content! Keep it up!

[@ahmedsoffy581]

i would to thanking to your amazing explaining . its sooooooooooooooooooooooooo much gooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooood

[@AverageJoe2020]

Nicely presented, Could you hook up the output to your oscilloscope and show us the frequency and waveform? I would be interested at least. Cheers, J.

[@DiodeGoneWild]

Good idea, I will try to :)

[@putraadriansyah8082]

@@DiodeGoneWild have you done that? I'm curious with the output :D

[@firefox1136]

@@putraadriansyah8082 It is a one to two khz oszilation. The waveform is something like a ringing if I remember corectly.

[@eliokarolinaclementekusibo9133]

I miss a view on the oscilloscope...

[@mohdjimar87]

This video is so usefull.good work. I m from algeria

[@tonyd1149]

Thank you for making and posting this video.

[@thesolderman861]

Very Relaxing with the Birds singing in the Background e.g. @9:45. Question: How about the Voltage pulses versus the maximum Reverse Voltage of LED and especially Transistor? For a 1,5V Battery this might be OK in most cases, but if you want to extend this schematic for using 2 LED in series, maybe then also working from a Lithium rechargeable cell will bring everything out of its usual limits.

[@johnoddvar1967]

Thanks for this one. I made it out from one single solar cell and then to a voltage dobler. Now i am charging a 12 V car battery with only one solar cell with an output of 0,5 V. I measured 17 V on open loop.

[@br.davidriccio5898]

Can I see your schematic for this project? Thanks

[@allexandruprroca6713]

AMAINSING EXPLAYN ON KZbin >KEEP IT UP MAN

[@levelrod]

That was great! This is a great project to get started learning about electronics. Simple enough that I can follow and useful too! Thank you

[@JUANKERR2000]

To save the need to identify the ends with a meter either use two differently coloured or sized wires or marked both ends of one wire with e.g nail varnish/polish.

[@1marcelfilms]

Replace the LED with a 2200k warm white led filament to make the light look like old lamp.

[@omsingharjit]

your explanation is great

[@nyakoi]

The circuit works with all types of cores and wire thickness. WIth white 5mm LED it works until the battery voltage reaches 0,38V.

[@igrewold]

What voltage are dead remote batteries? Are they like .9 or .8 volts?

[@ELECTROHAXZ]

Depends on the remote, mine uses them until around .8 volts but my computer mouse uses them until 1.3 volts, very wasteful.

[@pavelbires]

@@ELECTROHAXZ Huh, that's nothing, 1.3v, my sister's epilator is using the batteries up to 1.4v, big rubbish. I give her eneloops, which are charger max up to 1.48v...

[@ELECTROHAXZ]

Pavel Bireš darn that sucks, rechargables are generally rated only 1.2 and full charge is 1.3, so that's quite bad.

[@Vilvaran]

5:25 - Me: *cringes uncontrollably* Dude, chuck those ferrites in the oven, you can separate the cores in an instant which is really important for reusing them! Yes is *is* possible to use ferrite fragments, however all the air-gaps will ruin performance... Also the 100nF capacitor is actually necessary, may need to be of higher value where long-ish power wires are concerned. (I made a joule thief that operated in the megahertz range - the impedance of the wires caused it to *not work* until I chucked a decoupling cap on the input supply and then it worked just fine... This was a really 'fun' lesson in AC circuitry fundamentals!) Otherwise this is a really good one - I have that EXACT torch from when I was a kid, although mine has black plastic, with a yellow piece for the light...

[@brucebryant6483]

Very enjoyable creation thank you! Much better than crappy products. I enjoy your parts collection.

[@intel386DX]

Cool I remember this flash light, I hade a Black one, the hed is rotational :l

[@jamesallen6007]

Excellent. Many thanks. You have earned my subscription. 🇬🇧👍

[@varicruse]

you are great thank you for the detailed demonstration, very helpful

[@German_byte]

Just brilliant!

[@danmalaca3246]

I try this circuit and its work..many thanks mate.. :)

[@danfishermen5362]

Youre British

[@danmalaca3246]

Im filipino

[@danfishermen5362]

Im latvian

[@aptube6754]

I'm Indian

[@alibehrouz9833]

such a clever design

[@manish7782]

Thanks for Simply explanation ...

[@pohonbunga6271]

I Like it very detail and simple thanks 4 you

[@talonfluff]

You can use a radial wirewound ferrite core inductor as a transformer. Just unwind it and make a center tap and wind it back.

[@akaishi1583]

Another way to remove the insulation from those thin wires is to Just apply solder to it continuously, the insulation eventually melts off and the solder sticks. And because I didn't have a multimeter at the time, to test continuity I just attached an LED to a 2x aa batter holder with the positive contacts connected to some wires with breadboard connectors.

[@DiodeGoneWild]

You can also identify the windings by trial and error. There are just 2 possible ways of connecting it :).

[@saarike]

Really cool and interesting! My humble thanks!❤❤❤❤❤

[@bjornjohansson4911]

Dear Sir. Although, I am familiar with analog electronics, as well as this design, or because of that, I want to praise you for this excellent tutorial. Just the essentials. No less, no more, told by a positive, nice voice. (India? I actually don't care, but it was so easily understood even for an old swedish man). Solutions, like this, may raise in importance quite soon. We are now in a worldwide pandemic, where we have very little control at the moment. As an emengency light, it may be important to squeeze out all juice from a battery, before disposal, though it might be the difference of health and sickness in some cases. So. many thanks for this show!

[@question_mark67]

He is of czech nationality

[@bjornjohansson4911]

@@question_mark67 Thanks. 😀

[@temurnariashvili7526]

Hi! What was the point of using capacitor? And what is the capacity of yours?

[@yutan15silvia]

Using a common mode choke coil in the transformer can be easier to make.

[@NullPointer]

What about those ferrite rods you can find in AM radios? would those work as well?

[@mandovibrazrocha2295]

Thank you Teacher, cool.

[@pyotrleflegin7255]

Well explained -- many thanks.

[@harryseldon4818]

Many thanks, good job !!

[@Edmorbus]

Thanks for sharing

[@saeedvba5655]

thank you so much

[@stoyandimitrov9352]

true engineer!!!

[@singingzone3056]

Can I take BC 547 NPN transistor??

[@kennethcoutinho4439]

Too good bro

[@waelsadek81]

Is it better to use a transformer or coupled inductors for the joule thief ?

[@lez7875]

saudações. muito interessante e simples. sucesso.

[@igrewold]

Cool man, that's a great tutorial and good use of old/dead batteries. Just wondering, how many volts do you if you stick a 9v battery there? Thanks

[@justADeni]

it kills the transistor. try using some other for 9v

[@gristlevonraben]

Awesome, very awesome.

[@octavmandru9219]

good, but you could have used the scope to check the waveform.

[@cristianvoiculescu5545]

How can we calculate the frequency of the oscillation?

[@riloariichoariicho884]

Thats great.i will try making one for myself.everytime i watch your video it gives me knowledge. What is the name of that black L shape you winded with copper wire

[@englishrupe01]

That was the ferrite core, i believe.

[@firefox1136]

Those are scrap ferrite parts glued together.

[@brandonsihvonen8555]

What is the difrence between a boost converter and joule thief

[@ankitrajmahapatra4766]

Can I use any NPN transistor like 13001. Nicely explained though.

[@AWESOMEEVERYDAY101]

Ankit Raj Mahapatra yes as long as u know the pinouts

[@ankitrajmahapatra4766]

AWESOME EVERYDAY Thanks. 😊😊😊

[@prakashchandrabehera6437]

Can your joule thief light up a 1w led

[@vaibhavshhh]

Awesome trick. Thanks for sharing. where are you from (I'm from India) ?

[@DiodeGoneWild]

I'm from Czech Republic :). It seems that at least half of my viewers are from India!

[@TheJavaSync]

Indonesia

[@asimkumardas747]

India

[@diablo6774]

I am from India also

[@lijuminati]

Nope. I'm from Poland

[@filenotfound__3871]

How can i make it output 4.5V?

[@mystcat3]

It can, but the voltage drop is massive. Try lower resistance

[@filenotfound__3871]

@@mystcat3 in mv expirience it just heats up the transistor

[@legominimovieproductions]

That meanw if i take a potentiometer and connect it to the base of the transistor i can build a variable current output for a selfmade power supplie(atx power supplie as bench power supplie)

[@hukkabukka]

That was an antic sand paper. ☺

[@edgeeffect]

What year did you make this? As I understand, this was first published in a British amateur electronics magazine. It would be amazing to find that such information managed to cross "the iron curtain".

[@nekoplays7]

I made a amplifire from LA4440 IC

[@tahanlaoboy]

Thanks

[@Boris_Din_Dietrich__Hazim]

So can we use it to double the voltage?

[@rroge5]

i have used electrical circuit simulator app on smartphone to try to get joule theif to do higher power more current. nothing i did worked.

[@zuluflight5467]

Thats Great !!!

[@nikiamz6501]

Do you have electricity company caled "CEZ" in your country?:)Good video as always! :-)

NIK TECH Yes, in CR there is ČEZ, which means Czech Energetical Enterprise. :-)

[@attilarivera]

i have a *_3v_* _AM radio_ .. will it work with this device?

[@DiodeGoneWild]

The output voltage is pulsed, you have to add a schottky diode and a filter capacitor at the output. Hopefully the operating frequency of the joule thief will not interfere with the radio....

[@lukabread4099]

@@DiodeGoneWild what value should The cap be?

[@waqargul5435]

Whats the maximum voltage you can get out of 1.5V? and can we use it inside my mosquito killer bat?

[@sathyamurthyponniah124]

@Waqar Gil - I use a 3.7volt li-ion phone battery in my mosquito bat and use the phone and the charger to re charge the battery when it runs down.

[@Kostanj42]

you can use very cheap cores from china for 0,20€-0,30€ 10pcs, total cost without battery for me came around 0,5€. it's very useful and works great :)

[@JakubZahorik]

Skvela ukazka, Danyku :-)

[@kevinporter9797]

Always AWESOME!!! Very enjoyable, and educational to watch you at work as well as your cat, and dog, but I have a question. How did you start doing this??? You fit these videos like a glove lol

[@kevinporter9797]

It is very strange, but you remind me of my Doctor best friend. He is from Poland.

[@loraineprinsloo341]

I thought that the collector was on the right hand side?

[@MegaInformazione]

Poland: the Revenge!!!!

[@kirthlycarty8207]

Great video, question : Does it only work with dead or dying batteries?

[@g.d.8065]

No, it would work with any power source (within reason), it's just that this is mostly useful when the input voltage is too low to do any useful work directly. Part of why it's mainly used with LEDs is because LEDs don't really require that much current to light up, so what little energy is left can be used for a good amount of time. Also, the maximum current output will be lower than the current that goes into it, because it's converting a low voltage and high current to a high voltage and low current ("high" being relative here).

[@AWESOMEEVERYDAY101]

my joule theif not working. i used an inductor transformer and took out its core and removed tge origianal winding and then did the same . its not working.

[@norek7226]

AWESOME EVERYDAY Check if your coil is connected properly. The current in the first winding needs to flow in opposing direction to the second winding.

[@yurigagarin4974]

check for short circuit

[@danmalaca3246]

Check your xformer ..mine work well..cheers

[@justtinkering6713]

Not a switching psu. Blocking oscillator.

[@amaanqureshi1286]

Do you have patreon?

[@DiodeGoneWild]

I don't have patreon. Should I be self-confident enough to have one? :)

[@amaanqureshi1286]

DiodeGoneWild right now get a PayPal or similar donation link. Or do a poll among your audience. By the way I really like your content and style of videos. I've been binging watching your channel.

[@laszlovona]

DiodeGoneWild you should definitely be.

[@mohitbling6658]

DiodeGoneWild definitely

[@pyromen321]

Holy shit, why have I never used a knife to remove the coating from enameled copper wire?!??! That’s such an obvious and simple solution, yet I’ve always resorted to using a lighter and rubbing alcohol for some nonsensical reason

[@Charapaha]

Так, я не понял, а чего это вдруг все так сразу зафанатели от подобных преобразователей?

[@farisocap8828]

رائع

[@jaytee3472]

How about if you want to boost 3.7v to 12v. How many winding in choke should i turn.

[@123risu]

Very nice explanation & details. When we open a water tap, water flows.. But in an open circuit, current stops flowing. What an irony :-)

[@darrensimons5057]

I nees voltage booster circuits my amp needs at least 35volts and I only have 3.7vbattery and a 12v battery can u make more on amplifiers and voltage boosters thanx

[@অৰি-ঝ৯র]

Is it same as a Boost converter?🤔 If not, then what's the difference between this and a dc-dc boost converter?