DIY Wireless LEDs Made Easy: Step-by-Step Guide

[@stevetobias4890]

I have thought about building a chess set with wireless LED lights built into the pieces and the coil/s in the board with 2-4 x 18650 batteries.

[@gadi70]

Thinked just about the same!

[@hczylos2432]

Gonna make and sell this, hope you’ve got a patent pending. 😂

[@ezenelex]

that is so genius

[@Super_Natural_Power]

Chinese are reading this. Be careful !

[@webplayerxvii]

That's a lot of batteries.

[@oasntet]

As always, the build-vs-buy question is usually less about cost and more about specificity - you can tailor the build to a very specific project, whereas finding a pre-built version to meet some projects might be impossible. Plus the fun and learning of doing the build yourself, of course.

[@warmachine5835]

There's also the labor aspect--how much time did you spend prototyping, then building and testing the finished circuit(s)? I think this is the second half of the specificity trade-off. Your off-the-shelf components are ready to go, but might not be an exact match for your use case. A custom build can be made to your exact specification, but you have to spend the time to develop it to your specification.

[@MelissaMaya]

It's not really difficult, i also explained how to make these leds in my channel, but using SMD components, just like the ones they sell (in my kit, the emitter was working at 180khz for a change) and even smaller (the comercial ones uses CD43 inductors, and i managed to use CD32 inductors, a bit lower range and dimmer light, but still working). I'm glad more people is spreading this knowledge arround for DIYers. Great video!

[@atomic14]

Thanks! You have steadier hands and better eyesight than me!

[@m101ist]

What about in £'s sterling.

[@cacaokingdom3122]

@@m101ist If you buy the components in reasonable quantities with surface mount components it would be about 33p sterling.

[@stephendavies201]

Congratulations on producing an incredibly clear, well informed and crisp video -really a masterpiece of technical explanation.

[@atomic14]

Thank you:)

[@jensschroder8214]

Take an ICM7555 with R1 = 1k8 and R2 = 4k7, parallel to R2 a diode from pin 7 towards pin 2 and 6. And a capacitor 1nF to GND. That should be about 222 kHz. Mayby a high Ohm poti.. Already has 5 volts level for the MOSFET. If it is not enough, two logic inverters in between, which usually have powerful outputs. First one inverter and the 5 inverter in parallel for the 4000 or 74xx series. The components are cheap and can be soldered onto a small circuit board. Then there are hardly any hidden capacities and loose contacts.

[@atomic14]

Great information - makes this a lot more accessible for people who don't have a handy MCU.

[@wallkiller8080]

So it'll be possible to use it without mos driver??

[@atomic14]

Definitely worth a go if you have a suitable logic level MOSFET that you can drive with 5v logic. And you can drive enough current to switch it quickly.

[@RexxSchneider]

An ICM7555 is CMOS and will only drive a few milliamps, so isn't suitable for driving power mosfets directly. The CD4049UB isn't much better, although with five in parallel, you might drive about 50mA cleanly. The standard NE555 or similar should drive 100mA with a 5V supply, but you will still have problems with reduced voltage swing, probably to around 3V. A typical switching mosfet like the IRFZ44N will turn on with a gate voltage above 4V, but has a gate charge of up to 67nC, which will take 0.67μs to charge/discharge at a constant 100mA. The switching frequency used in the project is around 200kHz, which means an entire cycle takes just 5μs and each half-cycle is around 2.5μs. Having a switching mosfet in its linear region for a quarter of the time will cause problems. You just don't have enough drive without using a mosfet driver if you've only got a 5V supply to use.

[@RexxSchneider]

@@wallkiller8080 Not with any common power mosfet on a 5V supply.

[@Alluvian567]

This is nice. I was looking all over for how to do this like 5 years ago and came up pretty empty. I don't have the electrical skills to figure it out myself. I do love the very compact design of the original leds.

[@SolonTh]

It would be really cool to have these wireless LEDs inside some dice. Then make a dice tower with the coil in the base. So when you throw the dice they light up! Awesome, excellent video! Love the thorough explanation

[@mrtechie6810]

How will you balance the weight?

[@Reactivate100]

@@mrtechie6810 9 X 9 X 9. Some could be disabled? 🥰👋

[@Mopki3]

Product idea: A gameboard with led game pieces.

[@jhana.2023]

Your channel was a find on KZbin. A pearl. Very good ! Very good ! If it's up to me... everyone I know will know your channel. (from Brazil)

[@vameza1]

Amazing project!!!! Mainly because how you explore how evaluate the components needed in order to make work properly!!! Thank you for sharing!! Perfect for a science fare!!!!!

[@massioki818]

Im just happy there are still people, who like me can still enjoy this side of life. God bless you.

[@nonamenerds8157]

oh nice! Thanks! This is exactly what I was looking for - the plan is to 3d print a set of chess pieces (using clear for white and tinted resin for black) and put LEDs inside, powered from a coil in the board. This will certainly help to build this!

[@atomic14]

Nice idea! When you've finished send me some pictures or do a little video!

[@ionstorm66]

Was thinking the same thing, but for dice. Would have to make a custom jig to center then though for weight.

[@dailydriven]

Perfect usage. They have been using these for years in hobby models. For example gun damn models. When you set the model on the stand. They glow. The eyes and shield and.... glows

[@WistrelChianti]

Just some rough calculations on "without a gate driver" (sorry this one intrigued me). Looking at that trace, total time is ~660ns with fully on making up about a third of it. So at 222kHz you'd be spending about 5% of the time turning the thing on and off. Possibly not the end of the world but probably not superb either. (Apologies if I totally stuffed up on theory there - was just a guess)

[@vinny142]

Sometimes it's just cute to see people using age-old techniques asif it's something totally new and amazing :-)

[@notahotshot]

Oh hey look, it's a douchebag.

[@EritreanMedia]

Your teaching technique is amazing, I think I found my favourite channel SUBSCRIBED❗

[@ko5t1k]

Thank you! I am really like your videos with the "deep dive"

[@someoldguy383]

Good stuff, but for those of us who don't have electronic parts lying around already, or who would have no use for the excess that comes with buying in bulk, it's actually cheaper to buy from the Chinese. Still, it's good to have the option!

[@atomic14]

Indeed - the build vs buy is always a lot more nuanced than simple cost.

[@r.ccustomtruckingsydneyaus4632]

iv just purchased 6 sets of these for my 1/14 scale truck trailers. all wireless. love em. would have known about them if it was not for you. thank you

[@excrubulent]

This is fascinating, I have a very specific use-case where I will be buying the pre-made units because I need them to be very small, but I also want them to have light emitting all around, so I want to see how many LEDs each part can drive by just soldering extra SMD LEDs to the same leads as the existing one. I'll also have to check if I can do the trick of reversing some of them to use the other half of the waveform. Ideally I'd like 6 LEDs running off of a single inductor in a very compact little package. I"m really hoping there's plenty of overhead in the design, since LEDs really are very low-power devices.

[@bob2859]

Interested in a DIY approach to "long range" wireless power. Like a Yagi-Uda antenna, you could use specifically chosen passive elements to change the radiation pattern. Would be nifty to be able to point something around the room and see a bunch of hidden LEDs light up!

[@167mm167]

"long range" wireless power is interesting ...

[@peter.stimpel]

explained well enough to go DIY ... thanks a lot

[@YoutubeBorkedMyOldHandle_why]

I've been quite fascinated since I first saw your excellent video a couple of months ago. I have my version working with a 555 timer and a trimmer pot to vary the frequency. I couldn't manage to get the duty cycle close to 50%, so I used an 2N7000 mosfet to invert the signal, which also cleaned it up a bit, and then I fed this into a TC4420 mosfet driver. Maybe I'm pushing things a bit, but I've been using 12V across the power mosfet. My bench power supply tells me that I'm consuming about 2W of power, which seems reasonable. Everything seems to be working nicely, though I'm still tweaking things. One thing though: So far, I've been using a CBB film capacitor on the transmitter coil, but today I noticed that it was getting pretty hot. I suppose I could try turning the voltage down, but I'd rather not, since 12V improves the brightness. I see that you are just using a small ceramic cap, so I was wondering if you might have any thoughts on this? I've also been using SMD parts on the LED side. CD54/CD43 inductors, and 0805 LEDs and caps. I'm trying to find a way to solder the parts more efficiently. I'm thinking of making some tiny little DIY PCBs with 0.4mm copper clad, and using something like a paper punch to cut them into circles ... unless someone has a better suggestion.

[@atomic14]

That's great! You've certainly taken it further than I have. I would have a look at the ESR of the capacitor you are using. Maybe you can find one with a lower value that the one you have. I like the idea of the tiny PCBs.

[@andymouse]

Great video, definitely a 'DIY' option....cheers.

[@TradieTrev]

Super surprised how much current it generates without the pull down resistor on the mosfet gate. This little design really makes me think how they work, cheers!

[@atomic14]

It's really interesting, if you leave the gate floating then it can easily get switched on - and if you're moving a lot of current around it's easy to damage something.

[@WistrelChianti]

it's more that inductors resist a change in current, so if you keep things on, after a brief moment, you sort of have a short (but wire resistance etc). If you keep things going on and off quickly the inductor never quite gets up to fully conducting (it's busy resisting the constant changes in current). The resistor on the mosfet is more about just being certain it's at zero volts when off. Its a fun experiment to try (without driving big current) to try one without that resistor and see what you get. I've mistakenly forgotten them before and wondered why stuff doesn't turn off.

[@WistrelChianti]

Actually quick demo why you want that resistor kzbin.info/www/bejne/bqTae5J4o9iaopY you can see even prodding the gate with your finger can be enough to get it (at least partly) on

[@TradieTrev]

@@WistrelChianti That totally reminds me why we have RC snubber circuits for inductive loads on solid state relays!

[@WistrelChianti]

@@TradieTrev haha next level (to me anyhow)

[@large65]

Would these LEDs work through a wooden door of approx. 4 cm thickness? It would be interesting to have the LEDs wirelessly controlled from inside of e.g. a garage to lit the key hole.

[@atomic14]

I think so - they worked through some quite thick books. You would need to try it though. You can push more power through the driver coil - power it from 12 or 24 volts.

[@GhostsOfSparta]

If you can reduce the driver circuit to key chain size, then you can put LEDs behind key hole. So when you try to enter key it’ll lite the keyhole.

[@mrtechie6810]

Just turn on a light?🤷

[@GhostsOfSparta]

@@mrtechie6810 from outside using bluetooth? In lord of the rings hobbits, they couldn't find the keyhole in broad day light!! 🗝 🚪 If the keyhole itself shined then they could've save some time and suffering.

[@mrtechie6810]

@@GhostsOfSparta use a motion-detector floodlight. Or a Bluetooth switch that turns the light on when your phone gets in range. You could also put a tiny light behind the keyhole, on the inside. If you use an LED, the power is so low that you could have it on all the time.

[@PhantomArtcoding]

It is interesting to try making a large diameter reel under the table to surprise your friends.

[@manoslogothetis4247]

Would extending the cables from the inductors, in order to have the LEDs at a greater distance from them, affect their operation? I was wondering if I could use such an array in order to "wirelessly" power some LEDs located inside scale models. The concept is as follows: 1)Make a diorama-base with the large coil. 2)Put small coils in appropriate places inside the model (located as low as possible) 3) Run wires from the coils to the LEDs you need to power. 4)Place the finished model on top of the base, making proper alignment with the main coil and the internal ones (located in a certain area inside the model).

[@kissingfrogs]

Nice video. I am trying to think of a nice Escape Room prop to wrap around this tech as it somehow seems a perfect match.

[@atomic14]

That's an interesting idea - some kind of puzzle where you need to find the right place to put something so it lights up. Or when the lights are arranged so they light up they point to some clue.

[@WistrelChianti]

@@atomic14 you need to do a collaboration with playful technology channel me thinks :D

[@Chevchev2]

Thanks for the video. Is very good. Can you say how the construction of LEDs changes so that they light up with the frequency of a mobile phone?

[@TheElectronicEngineer]

That’s nice , using smd components, the leds can easly be made smaller. I see some comments of people wanting to implement this in a chess board… hmmm in that case tuned receivers could be a way to selectively lit up some leds while others don’t

[@alexstone691]

The cost could be improved significantly, using bjt push pull for the gate driving, making an oscilator using an opamp (lm358 is dirt cheap) and you could probably get away with using cheapo mosfet like AO34xx which are cheap even in my country and can even do 5A and turn on even with 2.5V

[@killerguppy2988]

Awesome work! I might have to try this project out. You can get some mcu's for pennies, or try using an oscillator chip or circuit. You can also get those SMD LED's and caps pretty cheap if you buy in bulk, so that will greatly shrink the size, but they're harder to solder. Now I just need to find a use for them.... I'm wondering if there's enough power for a wireless micro bugbot thing.

[@atomic14]

I think a low lower mcu could definitely be powered. You could also use the energy to charge up a capacitor for a more lower hungry device and then wake it for a brief time to do some work.

[@LadyCatFelineTheSeventh]

Would love to see something like this become a wireless Christmas tree lights. Perhaps hot glue on to a tree branch, hang the coil like an ornament to power them and no more wires for the cats to chew. How many lights will one coil power? It looks like each set has about a 9 inch radius, so it seems like it would require a few coils to decorate a tree. Not to mention linking them up. Hmmm. Maybe it's not wireless after all.

[@dreupen]

nice. I purchased the wireless led kit from Adafruit, and being inspired and added some components to a mouser order I was placing: 2.2mH inductors ($0.43 each), 240 pF capacitor, and red LEDs. I thought using 2 LEDs was a brilliant move, but it turns out not so brilliant. That is, 1 LED is much brilliant (~2X the brightness of an LED when using 2).

[@smoll.miniatures]

Where did you find 2.2mh inductors at cd43 size?

[@dreupen]

@@smoll.miniatures It was either Mouser or Newark.

[@damson3413]

This could have been done with a 555 timer with the appropriate passive components, and a mosfet. the microcontroller is overkill.

[@erikev]

Are you sure the shrink wrap on the inductors shield anything? This is not the case on the shrink wrapped inductors we use. Works actually slightly better with the wraps since the permeability is 1.00002. The resonance frequency changes quite a bit with the load you put on. Can you test out what it is by varying the oscillator for max power?

[@revinay8476]

Thanks for doing such a great work. Nice explanation 👍

[@AndyFletcherX31]

In a pinch you could drive the MOSFET with a 555 and save the cost of your processor board and driver chip.

[@darenlim1584]

I'd like to see these powering LED Filament strips. I do wish that the strips weren't wired at both ends but rathered them both be next to each other.

[@BeOurBee]

Would a small metal dish underneath the coil increase the effective range, or would that interfere with the signal by muddling up the frequency?

[@lapricap]

I imagine a small metal dish (assuming good conductivity) would make the LEDs not light up or reduce the range at least. The time-varying magnetic field from the base coil would induce currents in the metal dish that aim to reduce the magnetic field from the coil. So it wouldn't interfere by muddling up the frequency, but by reducing the power transferred from the big coil to the LED coils.

[@dailydriven]

These are used inside hobby models. Such as Gundam or cars. When you set them on the stand. They glow.

[@TheRcEngineer]

Very nice weekend project, thank you. Btw when you use a driver you dont need a logic level mosfet, any would do.

[@DL30Creations]

There is no sanctuary...... This explains how the movie version of Logans Run Lifeclock worked. City encompassed by the coil to power them. When they escaped they didn't work anymore.

[@Pyromancers]

You shouldMaybe you could give it a go with the bigger coil version too since those have much better range. Great work. Will replicate for my projects.

[@Hasitier]

Would it be possible to use a simple 555 timer as oscillator? So you would not need a MCU and also no gate driver because you can run the 555 at 5v without problems.

[@alexstone691]

One 555 timer can output only >=50% square wave, also don't know if the 200mA it can output would be enough for such a high frequency

[@user-rs8zg8ey2b]

Yes, no problem, and you dont need a FET driver, and if you keep the current under 200mA avg (check your 555 datasheet, not all 555 are built the same), you dont even need a FET.

[@alexstone691]

@@user-rs8zg8ey2b how do you do less than 50% duty cycle with 555?

[@RexxSchneider]

@@alexstone691 In a standard 555 astable circuit the capacitor is charged through R1 and R2 and discharged through R2 alone. Putting a fast diode in parallel with R2 to short the charge path through R2 allows the duty cycle to approximate R1/R2 and that can be adjusted to give any desired duty cycle. Note that with a 5V supply, the diode drop has a significant effect on the rough calculations, so some experimentation or trimming of values may be necessary. Using a Schottky diode would bring the observed times nearer to the ideal ones. There's a exposition at en.wikipedia.org/wiki/555_timer_IC#Shorter_duty_cycle

[@RexxSchneider]

@@user-rs8zg8ey2b A standard 555 won't source or sink more than about 100mA from a 5V supply, and you'll find the high output voltage is going to be reduced to around 3V, which is very unlikely to turn on/off a power mosfet properly, even if it is "logic-level".

[@CrazyCoupleDIY]

Great info, I am now your big fan

[@lisamuller1188]

Thank you very much.This is absoluteley stunning. I was wondering how changing the coil Turns and diameter would affect this built and which physical laws could help me figure it out. I quite suck at understanding induction, but would like to experiment with this for different output voltages.

[@zephsmith3499]

OK, you reproduced it, now let's see some improvements! For example, can you get more range with a larger coil size, or more power? Does tweaking the frequency improve the range?

[@xxxyz721]

What’s he best way to increase the range of the coil?

[@Arek_R.]

I had it working with shielded inductor but on top of a QI charger which pumps out awful lot of power tho...

[@zaidhussain5206]

Very interesting , thank you for sharing this knowledge

[@frollard]

Now I want to make this-ish but overkill...add a supercapacitor (there are some good cheap tiny options), and as someone else suggested, cast into resin...possibly with coils at right angles - the ali video showed the power drop off significantly when the pixels were rotated against the magnetic field) - add a bridge rectifier, and the cap, and you've got yourself some fun glowy marbles that ...do things.

[@toqeerahmed3016]

Will zvs driver or tesla coil work with the LEDs?

[@HobkinBoi]

Diy, for the same price as buy you could probably have a circuit that can have a better range and more current being able to be transferred

[@EasyOne]

Very well explained

[@devandestudios128]

What if I just use a 9 volt battery and a coil, skipping all the chips and capacitors and resistors and gates? Just current directly to the coil. Would that over power the LEDs?

[@atomic14]

It needs the oscillation to transmit the power unfortunately.

[@ahassan8103]

you should contact Mr. Tesla for more info! have fun

[@JohnPiperBoots]

Bingo LOL He would be an expert & appreciate this demo of induction if he were here today! :)

[@NimOCE]

I wonder if this can be scaled up to be effective in say 1 meter X 2 meter applications.

[@jvles5123]

Is there a way to increase the magnetic field? The lights work only a few inches away & I wanted to increase that

[@trinidad17]

The SMD LEDs are not hard to create, just use SMD coils, they are easy to get hold of and definitely can work without the capacitors although they don't perform as well they work well enough, and have to be REALLY out of tune to not work actually, so it's hard to make them not shine at all. So DIY LEDs + an induction heating driver can work as a starting point for your wireless powered LEDs.

[@ELECTROxigeno76.]

Exelent video document, tks 🎩

[@rachelmccullough7829]

What if you wanted somthing that would light up when on the wireless charger, but could be connected to a battery pack/on off switch so you could use it away from the coil as well?

[@marcelbauer5280]

Absolute great project! I have a lot ideas for that. Thanks for the Video. Is it possible, that you can make a video or a scematics (or someone else can?) for an easier version of the sender without an ESP? Like the idea, but this a bit an overkill. Some mention a 555 or something else?, but i am a novice in electronics, so maybe someone can help. Thanks in advance :-)

[@kreatifhandmade]

I love to learning 😍

[@surlycanadian]

Let’s say I wanted to make some liquid core resin dice, and I wanted to cast a a wireless led in a bit of shield of resin (maybe just 5-6mm in diameter), put it in the liquid core vessel with a weight on the bottom so that it always sinks to the bottom of the liquid core and shines upward, illuminating the top 70% of the dice. Now let’s say I wanted the LED to slowly flicker so that it looks like candlelight is radiating from the dice when rolled in a dice tray with the coil in the bottom of it. Would something like that be possible? I’ve seen people on Etsy put flickering leds in miniature terrains, like wall torches, fireplaces and campfires, burning debris ect, but it’s wired to something that I assume has the flickering element “programmed” into it and then connected to a battery obviously. What would you have to do with the coil and its power supply (if anything) to cause that flame flicker effect I’m interested in? Thanks in advance.

[@jurgmanx4644]

Yes, but this tech isn't really that bright. I got it to work, but you would need to super tune the transmitting coil with what is used in this video, run at 24v high power. There are tons of dead spots around the coil. The coil varies output power (brightness) a Lot rotating in 3 axis. I was gonna use this to power minis with light up lanterns, torches, etc. It works, but a coin battery (2032) is just better. Better go with a Big D20, and the coil under a THIN dice mat at the bottom of a dice tower. If you really can cast dice perfectly, let me know, I can send you what makes the flickering circuit work.

[@ScibbieGames]

Hang a load of these in a large room and make some antenna's Could be a volumetric representation of the fields?

[@TalkingGIJoe]

love it! thanks for sharing!

[@Scootercorn]

Is it possible to build a modular (linear) charging platform so that the wireless LEDs would be individually addressable via their position in the sequence? (E.g. a strip of 4 "slots", configured so that each slot would light up individually in increasing sequence. In such an arrangement, a person could insert/remove different LEDs in those slots but they would always light in the same sequence) Source: I have many RGBIC led strips at home, but am curious if a more modular platform could be made for repurposable needs.

[@patrickjeromeobaldo2450]

There are severals ways: have separate coils for each position in which the color data is fed through each coil is one example.

[@WistrelChianti]

really interesting video - thanks!

[@smoll.miniatures]

Big Clive said it was a 330pf cap? Which is correct?

[@bitsurfer0101]

Where did you find the resonant frequency calculator?

[@normanbeaulieu4204]

So how can I creat a transmitter that would cover a shelf area on 11 inches X 23 inches or 28cm X 58cm?

[@federiconovolissi7067]

if instead of single LED i use a LED module, I need to change the value of the inductance and the capacitor?

[@MrVictorchase]

Any way to make a selectable version of this? I.e. to be able to turn on or off a particular LED from the group?

[@squishthecad]

How realistic would it be to tune these on 2.4GHz and let it light up next to the WiFi router / Phone ?

[@Umski]

Hmm, tricky, aside from the power from the device and the manner in which it's transmitted, to achieve the resonant frequency of 2.4GHz, even with the smallest value capacitor of 0.1pF, you'd need to find an inductor value of 0.04uH which would be challenging...

[@mrtechie6810]

@@Umski use PCB traces instead of discrete components.

[@Umski]

@@mrtechie6810 maybe, but realistically even a perfect 2.4GHz patch antenna may only achieve at best a -30dBm sensitivity which is 0.001mW of receive power crudely speaking - even the small LEDs shown need more than that to light up :/

[@tiagotiagot]

Would it be possible to have something of similar size, but tuned to the mains frequency? Is there enough emissions from the wires on the walls to light up a LED? And what about something that works on WiFi frequency range and will gradually self-tune to the strongest frequency in the range it picks up? Would there be enough energy to light up a LED that way?

[@ennix7477]

@atomic14 Is it possible to make the LED addressable, to control each LED, especially for RGB. If yes, how?

[@TheNewTravelSource]

Great vid! Are you able to make the tx coil an oblong or pill shape, rather than a full circle?? Thanks

[@atomic14]

I believe so - I’ve certainly seen coils on aliexpress that are oval shapes.

[@Viixle]

How does a novice start these projects? Are there any sets, equipment lists, preferred projects or courses to learn from? I've watched this video 3 times now and I'm still not confident in starting. Any advice?

[@youdicreator]

Terima kasih banyak, ilmu yang sangat bermanfaat

[@Viixle]

What Oscilloscope do you use? you said 220 KHz or so, The ranges I'm seeing for purchase are in MHz (I could be dumb).

[@user-rs8zg8ey2b]

In addition to adding a LED in reverse to the main one, try adding 3, 4, 5 or more led's in series (instead of one), the inductive kick voltage can power many led's in series, and no need for the cap across the led imo (actually its not helping at all at that freq), and the same with the drive coil cap, replace it with a string of led's + resistor, its free energy in the since your cap is just snubbing the drive coil kickback voltage, why not use it to power some leds. Try it and report back.

[@ericoppel5698]

Could a circuit be designed to drive LED strip or tape lights so that they could be attached with cable ties or clear tubing to 40vac extension leads so they light up when the cable has mains power applied? That would be useful!

[@MizzItalia8]

Can you get ones that have a slow twinkle?

[@galenbean3606]

A 555 timer will drive the mosfet directly: KISS is the rule

[@ibrahimkocaalioglu]

How about a single npn transistor with 1.5V battery. This is the simplest and cheapest wireless led solution and it works.

[@phuonglee765]

Can you public a full schematic?

[@MrCarlito5656]

I need these where can I buy them...Thank you

[@jafetgonzalotorrescortes1287]

Could someone please tell me what mosfet was used in the video? I will thank you very much

[@chrisk6033]

put them on flying saucer that levitate ( you can do it from Floating Pot )

[@albertshilton5336]

How long would the batter last considering the constant load of the coil or coils with or without led load?

[@christianbock8592]

Nice video, as a layman I would be interested, how small can the coil be? I am thinking of a 20mm diameter coil for a single LED for model making.

[@xaverelgin8718]

How easy would it be to fab the inductor in house with some investment it tools and materials? Is there any literature you can recommend that can explain wire windings/gauges and any fabrication methods for the core?

[@yugdesiral]

how hot does the coil get?

[@nlo114]

Would a 555 drive the power FET directly? Bearing in mind the LED coils are only doing mA, how about SM inductor, cap and leds?

[@kissingfrogs]

Is there any value in attempting to maximise efficiency by varying drive freq while looking for peaks or troughs given all the component variations

[@user-rs8zg8ey2b]

Sure. I think more turns on the drive coil will go a long ways in increasing EFF and distance. Every turn multiplies the magnetic flux, this is why relays/solenoids/etc have hundreds/thousands of turns, to make them more EFF.

[@GoatZilla]

do they make commercial IR ones?

[@rhondastoops9683]

I really need to buy some of those please don't wanna say why cause don't want no you stealing my ideal lol this is what I've been looking for

[@pollpolle]

Hello, if someone can help me, I really like those wireless led, but when I want to buy them it's written than near metal the coil can burn. I want to buy them and to install them on my diecast (model car) for front and behind light. So because there are metal fabric I can't use them ? Thank you for the help

[@KeyCe]

why not use 555 + mosfet ?

[@atomic14]

It's quite hard to get high frequency on the 555 with a breadboard circuit. The mark to space ratio on the standard circuit is also always >50%. Using an MCU gives a nice easy way of generating the required frequency with an easily adjust mark to space ration.

[@KeyCe]

@@atomic14 ​ @atomic14 FYI hmm.. kzbin.info/www/bejne/hYnWpmVvgMR0ppY

[@WistrelChianti]

@@KeyCe as a relative beginner to electronics, I've found getting my head round a 555 to be one of the hardest parts so far. Compared to programming microcontrollers to kick out a certain duty cycle, theres a lot to learn for a 555 even if you are just following some configuration instructions. Understanding how they work involves a lot more. Sorta ironic given they were what was churned out when I was school... but then again I didn't go to school in the days of cheap microcontrollers.

[@RexxSchneider]

Because driving power mosfets at switching speeds of 200kHz from a 5V supply is hard work. They need their gate capacitance to be well charged or discharged to avoid excessive dissipation. That means you need to pick a mosfet that has a total gate charge low enough to be efficiently charged or discharged by the 100mA or so that you can extract from a 555. Because even 100mA will pull the high output of the 555 down to around 3V, you'll also need your mosfet to have a gate threshold voltage well below that. Something with a total gate charge of no more than 10nC and a Vt of around 1.5V would probably be okay at 200kHz, but the only mosfet I can think of with that sort of spec is the AO3400A. You won't get away with just any old "logic-level" mosfet.

[@WistrelChianti]

@@RexxSchneider interesting! Thanks for that info