Why does your Microwave waste half its Power?
The circuit inside a microwave oven is a half-wave doubler, an incredibly inefficient design. How does it work? Why do we put them in microwaves?!
Huge thanks to Mehdi Sadaghdar (ElectroBOOM) for the consult:
/ @electroboom
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TIME CODES
00:00 Cold Open
00:45 Half-Wave Rectifiers
01:44 Giant Transformer
02:42 Giant Capacitor
04:12 ElectroBOOM Rant
05:35 Low-Voltage Analog
06:32 Diodes
07:36 The Capacitor's Purpose
09:17 Half-Wave Doublers
10:20 Summary
10:54 Outro
11:28 Featured Comment
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Corrections:
01:32 "Utilization" would have been a better word than "efficiency." Half-wave rectifiers have a 50% utilization, not a 50% efficiency. They only utilize 50% of the provided voltage.
01:57 Phone chargers from the 1990s and early 2000s were simple transformers. Modern phone chargers are a more complicated design called an "Switch Mode Power Supply" or SMPS.
Пікірлер: 1 900
*Clarification:* By saying half the energy is wasted, I only meant that it was available but unused. In other words, the device doesn't take full advantage of what the wall is providing. It only uses 40-50% of the provided potential. I never meant to imply that the energy was dissipated as heat or dumped somewhere else. "Wasted" and "efficiency" felt like good words for that, but apparently I was wrong given the response in the comments. There's some ambiguity there that I did not anticipate. Oops! In hindsight, I can see how this could be misleading. *Minor Correction:* Apparently, modern phone chargers are made with SMPS transformers rather than magnetic transformers. I learned about them in the early days of mobile phones when they were all magnetic transformers. I had no idea they changed the design. This doesn't really affect the video, but thanks for the correction anyway. It gives me another rabbit hole to go down.
@maxxiang8746
Жыл бұрын
I think phone chargers usually don't use piezoelectric transformers, but just high frequency ferrite transformers optimized for flyback converters.
@BlackyBrownDestruction9337
Жыл бұрын
Thanks for the warning, I was planning on fixing mine but decided to buy a new one
@misterlau5246
Жыл бұрын
🧐 That's better, PhD Lucid 🤓🖖
@ScienceAsylum
Жыл бұрын
@@maxxiang8746 Thanks. I've edited that word out of the comment until I do more research into phone chargers.
@jeffpkamp
Жыл бұрын
I have a class 2 12vdc power supply. It's about 10-30x heavier than my switched mode 12vdc power supply and only able to source half the current (1a vs 2-5a).
Hey awesome, the scope survived!! oh and good, you survived too! 😁 great video!
@mukundyadav6913
Жыл бұрын
Someone: Avengers endgame is the greatest crossover of all time Mehdi: Hold my full bride rectifier Nick: Hold my 2,999,792,458 clones
@omsingharjit
Жыл бұрын
Mehdi - why not microwave uses efficient smps Stepup ?
@KeysightLabs
Жыл бұрын
I guess I'm shipping you another probe lol
@samuraisystemsllc
Жыл бұрын
Definitely need you to weigh in on the title, oh great master of the full bridge rectifier. We really don't think it's accurate to say it "wastes half it's power". Please respond Senpai. 😉
@SeanBZA
Жыл бұрын
@@omsingharjit Because that is a lot more expensive, so you only find this on the high end microwaves made by Sharp and Matsushita, who make them that way. The transformer, capacitor and diode are cost wise a third the cost of the microwave, and the magnetron is half, the rest being the steel case and everything else. You only have inverter microwaves at the top end of the market, never at the $40 Walmart special end. For inverter you start at $230 from what I see online, and go up in price then.
Unless I misunderstood something, the half-wave rectifier doesn't actually waste half of the energy (in the sense : dissipating it to heat) ; it just doesn't let power go through 50% of the time, but during the "blocked" half-period, no energy is taken from the source.
@axelBr1
Жыл бұрын
That's what I was thinking.
@eskiltroll
Жыл бұрын
I agree with you. It’s not wasted (turned into heat or something), it’s just not used.
@martin09091989
Жыл бұрын
Thank u, so i don´t have to tipe so much! ✌
@samuraisystemsllc
Жыл бұрын
That was my assumption, as well. There will be losses from the transformer from eddy currents, and maybe it even saturates a bit, but it's nowhere near "Half its power".
@zygintasmiknius9729
Жыл бұрын
so whole why your microwave waste half its power thing is incorrect? :D
Judging from the amount of damage in the small scale version of the experiment, not trying to mess around with the real thing was extremely wise decision 😂
@ScienceAsylum
Жыл бұрын
Agreed.
@zrglow4450
Жыл бұрын
One can't be too cautious when dealing with powers surpassing human body durability.
@pepcorampouch4787
Жыл бұрын
sure bruddah, dont touch that shit, the inside of a microwawe kills more hobby electricians than ANYTHING related to electronics on this planet, it will fry ur nervous system and brain so bad that youll be dead dead before you hit the ground, its srsly not funny...
The collab we didn't know we wanted, but the one we deserved.
@hancarv4705
Жыл бұрын
Are you kidding? it as has been my wet dream for ages
@northgrave
Жыл бұрын
My first thought when Nick started talking about rectifiers was that Mehdi should be consulted. Little did I know!
@ScienceAsylum
Жыл бұрын
@@northgrave Apparently, I thought the same thing when I was researching this 😉
@NoActuallyGo-KCUF-Yourself
Жыл бұрын
It makes so much sense in retrospect.
@N0Xa880iUL
Жыл бұрын
@@NoActuallyGo-KCUF-Yourself Absolutely
Love the way Mehdi called it a megatron . . 😀
Half wave rectifiers don't "waste" half the energy, they just don't use it, so it stays in the system. Makes a big difference as dissipating half the energy would be a nightmare depending on how much power you are drawing with the half wave rectifiers.
@gordonspond8223
Жыл бұрын
Exactly.
@chrisjacobsen1659
Жыл бұрын
This was almost word for word, what I was gonna post. ^^^ that exactly "waste" is very very much the wrong word.
@ScienceAsylum
Жыл бұрын
I've pinned a comment clarifying.
@gregorymalchuk272
Жыл бұрын
It introduces harmonic distortion and low power factor to the power grid.
@csehszlovakze
Жыл бұрын
@@ScienceAsylum do we have any ballpark numbers on how much energy is wasted *as heat* in this setup?
You are mixing duty cycle (conduction angle) with efficiency. With a half wave rectifier you still can get almost 100% efficiency, you just waste half of your conduction angle, so half of the time your rectifier is not pulling electricity from the wall.
@alexrvolt662
Жыл бұрын
yeah that's my thought too. At most you could say it wastes half of the power in the sense : the time-averaged power is half what it would be without the rectifier (so the device must be sized to allow 2000 W, where you have 1000 W "effective" only). But saying that it wastes half of the energy is misleading, bc no energy from the source is lost.
@ScienceAsylum
Жыл бұрын
I clarify in the pinned comment.
The half-wave rectifier is not wasting power or energy. It is just not utilizing the other half-wave. No current is drawn during the other half-wave thus no momentary power is taken from the wall outlet, thus also the integral over all negative half-waves and thus the energy consumed is zero. The only losses are in the finite forward voltage drop over the diode when it is conducting, the tiny leakage current in reverse direction and the fact that the load does not behave like an ohmic load and thus generates harmonics in the electricity grid.
@pwnmeisterage
Жыл бұрын
A typical microwave oven taps some AC power for the lamp, fan, and turntable before it goes through the HV transformer. Not to mention any AC power which is tapped off for other power transformers (to power magnetron and triode filaments, the timer and control panel, etc). So in practice much more than half of the available AC power is utilized.
@uwezimmermann5427
Жыл бұрын
@@pwnmeisterage in most cases those are insignificant in comparison. And in my statement I was only referring to the half-way rectifier not the total consumption of the microwave oven.
Imagine being me, waking up to find @ElectroBOOM putting my probes in a microwave
@ScienceAsylum
Жыл бұрын
😂
@HAWXLEADER
Жыл бұрын
Gotta say, I think your products are great! We use them at the company i work at and they're very professionally made!
@KeysightLabs
Жыл бұрын
@@HAWXLEADER thanks!
@alexanderquilty5705
Жыл бұрын
Just a small arm and a leg for hobbyists at home 😅🥲
@thomasdavis4253
Жыл бұрын
Having a working relationship with Mehdi, you should know it is only a matter of time before he puts anything in a microwave...
Enjoyed seeing a "trained professional" who knows "how to work with electricity without..." so easily fry a diode and bake a capacitor. Another fun and educational lesson in your library. Loved it.
@ScienceAsylum
Жыл бұрын
😆 Sure, but I didn't get hurt!
@paulmichaelfreedman8334
Жыл бұрын
I often play with breadboards and home made designs, and I cannot count the times I've blown up Electrolytic caps by putting them in wrong way round. Always that little pop, and then "Uhhhh!" (me)
@jskratnyarlathotep8411
Жыл бұрын
@@paulmichaelfreedman8334 tantalum caps do the same, but much more violently, btw
@Lucky10279
Жыл бұрын
@@paulmichaelfreedman8334 Why not just use unpolarized capacitors so you don't have to worry about it?
@iamjimgroth
Жыл бұрын
@@paulmichaelfreedman8334 I actually haven't had it happen one single time. That's not because I'm awesome. Rather I'm kind of crap, but I've been lucky as a leprechaun for many years now.
As a kid 9 year old started playing with electricity by blowing up capacitors for 9 transistor radios with my RC car power supply. Uncle got me the radio on my birthday, only lasted a month before I took it apart. 58 years later I'm a retired electronics engineer, life long electronic hobbyist still fascinated by electronics still blow up stuff.
@ScienceAsylum
Жыл бұрын
Sounds like electronics really had an impact on you 🙂
@marquisdemoo1792
Жыл бұрын
In the early 1980's, whilst working on a faulty device designed to detect trigger signals for remote control bombs in an Ops Room in Northern Ireland, I mistakenly assumed the circuit was rated for 12V when in fact it was 6V so on connecting a 12V battery the electrolytic capacitor exploded filling the Ops Room with little bits of foil. It did not make me popular.
@johndooley8837
Жыл бұрын
My age and story is very similar to yours. I seemed to have had some genetic electrical knowledge at a young age. My dad was an electrician (as was his father) and I would use things he had around to wire up batteries, lights and switches that actually worked without ever being shown how to do it. Later when I was about 12 I was given a volt ohm meter and the book Radio Amateur's Handbook, what a book, read it cover to cover many times. Using the books information about power supplies, circuit schematics, dipole antennas, TV frequency charts, coil winding data and using parts from old scraped equipment and vacuum tube TV sets, built a 750vdc power supply and basic oscillator transmitter that could screw up every TV for miles around. Anyway have to go, there are a couple of things on the bench that I want to take a look at..
@laughing5559
Жыл бұрын
Great username!!
@laughing5559
Жыл бұрын
Took electronics in high school. The lab needed some new bench power supplies but couldn't afford the full price so the school bought kits which had to be assembled by the students. Everyone gathered around the power up of the first completed kit. The cover had not been put on yet. When the switch was flipped there was an explosion and the air in the room became filled with something that looked like feathers. You guessed it! The large primary filter capacitor (electrolytic) had been installed backwards (polarity reversed). That was a lesson I never forgot.
Congratulations on 600k! Your uploads are BRILLIANT! Cheers from England.
@ScienceAsylum
Жыл бұрын
Thanks! I'm still shocked 600k people want to follow my work.
@bytefu
Жыл бұрын
@@ScienceAsylum Oh come on, you've got some brilliant episodes, you put so much effort into them and explain things much better than most KZread scientists do. In fact, you should have much more subscribers, given how good your videos are.
Great to see you again, Nick ☺ Mehdi's guest spot was hysterical AND informative- as always. Three Cheers for Science Asylum and ElectroBOOM!
@raven4k998
Жыл бұрын
imagine how powerful a microwave would be if it's transformer was 90%instead of 45% efficient🤔
I've always found the cavity magnetron to be the most elegant piece of engineering ever made. So many concepts and scientific fields involved in its inception, but ultimately a hunk of shaped metal that is easy to mass produce. It really is genius, the poetry of science.
@raven4k998
Жыл бұрын
hey it works it has always worked that's all that matter's
@baomao7243
10 ай бұрын
A SUPER clever concept using an electron beam and stamped metal to form the right geometry for the desired RF frequency. The lost art of tubes.
Two of my favorite youtubers in a great collab! What a great week! Thanks God! Although Medhi isn't a little crazy. He's COMPLETELY INSANE! Lol. Love you guys.
@jamescomstock7299
Жыл бұрын
Firmly second this!
@arthurmee
Жыл бұрын
Me too.
@FridayParanormal
Жыл бұрын
I was thinking the very same thing lol!
@davemarm
Жыл бұрын
Think you misspelled "Mehdi"
@arthurmee
Жыл бұрын
@@davemarm yes you're right. I'll correct it. Thanks.
Nice to see you and Mehdi working together 💪
Having learned a good chunk about sound-waveforms, I find other varieties of waves fascinating-props to your little-craziness for this demonstration!
This actually explained some key concepts from electroBOOM videos for me, like the rectifier ⚡💡 Thanks guys!!💙
@ScienceAsylum
Жыл бұрын
Happy to help! 🤓
The magnetron is in itself also a diode, and a load. The regular diode conducts on the positive half cycle, charging up the capacitor, then, on the negative half cycle, the magnetron diode starts to conduct, with the forward voltage being the 5kV, as power is being generated in the spiralling electron flow inside the magnetron, charging the capacitor to zero, then to -2.5kV at the peak, with the magnetron then seeing briefly the full 5kV. Thus the 2 magnets in the magnetron, there to make the electrons spiral between the hot cathode, and the grounded cold anode. The spiralling electrons create resonance inside the magnetron in the cavities, and this is at 2.4GHz, fed out via a tap in the one cavity via a feedline to the end cap, where it is introduced into the waveguide cavity at the top, and from there through a RF transparent window into the large oven cavity. the magnetron will start oscillating at some voltage between 3-4kV, absorbing the energy out of the capacitor and transformer, so while it only is being turned on for a half cycle, the energy is basically doubled, as the other half cycle is storing energy to be used then. No Beryllium oxide in the commercial microwave magnetron, it is way too expensive to use in that cheap product, so instead it is either white, pink or purple fused aluminia, aluminium oxide crystal, otherwise called when the crystal is large and not a powder, ruby. Here just a high temperature ceramic insulator. But the magnetron is still dangerous, the 2 strong magnets can shatter if slammed together, and they will attract small metal dust to them. Also never run a microwave with nothing in the cavity, the energy not absorbed in the load is reflected back into the magnetron, heating it up a lot more thna normal, and eventually the magnetron will become too hot, and the thermal cutout for the magnetron will turn off the microwave, or the transformer, till it is cool enough, and another turns off the microwave if the cavity itself gets too hot.
Not a bad description. It turns out the positive half cycle is used to boost the negative half cycle so the energy isn't lost. The magnetron uses a negative 5,700 volts not positive. That particular tube (yes, it's a vacuum tube) doesn't like continuous operation. It likes to be hit with pulses of energy. 60 times a second, bam a new 5,700v pulse.
I like this a lot, nice to take a break from things like gravity and entropy (which can hurt my brain) once in a while!
@ScienceAsylum
Жыл бұрын
Agreed. I always need a break and I had fun with this one.
@artdonovandesign
Жыл бұрын
I'm still trying to wrap my head around entropy and information and the Landauer Limit!
@satibel
Жыл бұрын
At least gravity keeps you grounded.
@michaelcherokee8906
Жыл бұрын
Goes to show the rich diversity between us all. I can grasp gravity and entropy just fine, to me it's completely intuitive. Involve electronics or algebra and I check out.
50% of the energy is not really wasted, though. It's just not used, but it doesn't get turned to heat or anything. In other words it doesn't end up in your energy bill :)
@ScienceAsylum
Жыл бұрын
I clarify in the pinned comment.
@Gurux13
Жыл бұрын
@@Kevin-mp5of they are unlikely to do that. Also, even in terms of apparent power it's not 50% wasted :)
“You don’t need it to be perfect. You just need it to work.” Engineering in a nutshell.
@lajya01
Жыл бұрын
and programming.
@crimsondragon2677
Жыл бұрын
@@lajya01 Coincidentally, I learned both from the same teacher.
@ScienceCommunicator2001
Жыл бұрын
But I want it to be perfect, and work
How did you make this video, colab with Mehdi, talk about rectifiers and not once did we ever hear, "FULL BRIDGE RECTIFIER!" ? :-) Great video.
@hoggif
Жыл бұрын
I'm sure it has been cut out. I find it too unlikely it never happened! :D
@omsingharjit
Жыл бұрын
Same Question A fool bridge Rectifire
Always good to hear from Nick. Great stuff brother 👏
Love your channel! No plans to ever take one apart but I appreciate everything you put into this vid!
@ScienceAsylum
Жыл бұрын
Now you don't have to 😉 because I did it for you.
There is a micro wave (called „Dialog oven“) ait works so precisely it is able to cook fish within an ice block.
Great video, learn some new stuff, really enjoyed the circuit tour and seeing the scope in use. Just really like electronics 😎👍🏻👌🏻 Thanks Thomas Mogensen
I had my OTR microwave suddenly stop working a few months back, and it took a bit to find the fault. First I thought it was the door switches, but replacing those did nothing. Then I decided to check the capacitor, which rightfully scared me as I already knew how dangerous it could have been. So after unplugging, I did a very similar method to what you employed with the pliers and piece of wood, hehe. Turned out the capacitor was completely bad and shorted. Found an OEM replacement for like $15 (just had to search for matching parameters), and the microwave came right back up and running.
@ScienceAsylum
Жыл бұрын
I'm glad you survived 👍. The microwave at an old job failed once. Turned out to be a couple burned out thermal sensors. Easy fix.
@rafflesmaos
Жыл бұрын
@@gags730 Thanks for the tips! I actually have a few good multimeters already from having to work on other electronics stuff, including an LCR meter for the trickier things. You're right, I should have checked the diode, hopefully it's still good and will continue to be good until I move to a different place and get a new microwave regardless :) This is the second time I had an issue with this microwave too, but at least between the first and the second there was a span of 7ish years of no issues. The first issue was it breaking literally a year and two months after purchasing (aka just out of warranty). That one took a while to figure out, but thankfully the manufacturer included a full schematic. Before finding the schematic, I checked every thermal fuse and saw no problems. Looking at the schematic, I realized that there was one more thermal fuse buried way off on the other side of the microwave. Disassembled the microwave further to get to the fuse, and saw that it just melted and broke the wire due to a bad crimp. Had to get a new temperature and voltage rated wire, new connector, new thermal fuse just in case, crimper, etc... still way cheaper than getting a new microwave or hiring someone else to fix it :D
@rafflesmaos
Жыл бұрын
@@gags730 Yep to both questions, including convection cooking. For that year before the connection failed I had been sensing a slightly burnt plastic smell... that was apparently the connector slowly melting under high load until it finally failed. Why, have you seen this type of failure before as well?
Your videos are always great. I bought your book! I live in wyandotte so ik about downriver so awesome you are from here! Keep up the good work and I will hopefully be Patreon supporter really soon when i finish school!
@ScienceAsylum
Жыл бұрын
Thanks for buying the book! I hope you like it 🙂
Yep, now I'm even more terrified of microwaves.
@ScienceAsylum
Жыл бұрын
There's a reason they usually have a warning label telling people not to open the casing.
Huge fun, and with Mehdi as technical expert, what's not to like? Leakage inductance in those transformers is the key design element that helps control the peak current without resistive loss. That's the really clever bit of the ultra-simple design. How magnetrons work is like blowing air across the top of a bottle to make a musical note, but using electrons in a magnetic field and "blowing" them across the edges of lots of metal "bottles". Total magickery.
@MachiningandMicrowaves
Жыл бұрын
@@gags730 The history of development of the cavity magnetron is fascinating, the basic principle was understood from the early 1900s but the compact multicavity magnetron was developed with the aim of making an aircraft- based radar. The Tizard Mission followed the surge of development by the UK General Electric Company and the 10 kW version was one of the technologies shown to the US committees in the search for a manufacturing facility and finance. I should do a video about the history and tech detail, but I'm a bit tied up with my work on the Great Seal Bug project for BBC television and projects on Gyrotrons and a quadrupole mass spectrometer.
@gary.richardson
Жыл бұрын
I'd love to see a video produced, similar to how Jeremy Fielding does on his channel. If you haven't seen his channel, he has put together some good explanations geared toward the non-technical
@MachiningandMicrowaves
Жыл бұрын
@@gary.richardson Jeremy is a brilliant presenter and engineer, I've watched his channel since he started and he's definitely a role model.
Love the cameo and really cool visuals! Thank you thank you!
I got really scared for Experiment Clone for a bit there. 😲 I'm glad it all worked out. This was so cool Nick!
@ScienceAsylum
Жыл бұрын
ElectroBOOM, saving lives.
4:45 the great realisation 😂😂
A Collab with Electroboom? Christmas has come early this year.
2 of my favorite channels coming together for this. Awesome guys😎👍
1st video i stumbled upon from your channel. Sympathic host, funny and yet educating. Yeah that's an insta sub. Much love.
Nice to see you covering the Doubler. I don’t think I’ve seen someone explain the difference in the voltage you can get simply by changing where you put the load in that simple circuit since my EE classes in college… 30+ years ago. Nice!
I didn't know all that was going on inside my microwave. Thanks for rectifying the situation! 🙂
@ScienceAsylum
Жыл бұрын
Good pun 👍. Glad I could enlighten you.
I SUBSCRIBED TO YOU IN THE FIRST 9 SECONDS because of the energy you bring i know for sure this will be interesting video channel.
This was a perfect time for that collaboration. It’s how I originally found your channel. Now I’m back after taking apart an older microwave, and finding out it was old enough to contain beryllium. Thankfully my local (public) electricity provider takes dangerous goods at no cost.
Great video love it that your doing experimental stuff, yes please show us in more detail how the magenatron emits microwaves using this electrical wave! 🤩
My two favorite youtubers finally together spreading knowledge. Dope!
Thanks for another super fun, Awesome video, Nick!
this video earned you a rung bell keep up the explanations about electrical waves and circuits that manipulate them its such and under discussed topic for obvious reason most people cant even understand it let alone break into easily digestible bit like this
@ScienceAsylum
Жыл бұрын
Thanks! Glad you appreciate it.
A great video and a forceful reminder to me to never, ever take a microwave oven apart. Loved the collab.
Never realized it was a half wave doubler! You learn something new every day.
Awesome video! Loved the cameo and how your lower voltage circuit matched the microwave one.
@ScienceAsylum
Жыл бұрын
Safety first 👍
Another fantastic video. Love the way you explain topics, thank you!
Re: not talking about angular diameter turnaround. I think it's less that we perceive it as an obstacle, and more that they think people will find it to be an uninteresting detail that they can't prove with pretty pictures. Basically, it contributes to cosmological surface brightness dimming, and statistical statements about the size of galaxies compared to what we expect. Without context about surface brightness being constant in a non-expanding universe, or comparative measurements of galaxy sizes, it just isn't as easy to grasp in a single picture as "further things look redder".
@ScienceAsylum
Жыл бұрын
That makes sense. Scientists don't always have a good perspective on what the general public will find interesting.
A 900 Watt microwave oven don't waste other 900 Watt as heat. The half wave rectifier simply doesn't present a load to the secondary winding of the HV transformer, when the diode is reverse biased. This load unbalance cause the magnetic field in the transformer core to be skewed toward one polarity. In theory it could saturate the iron core, but the core is designed to operate that way. The current peaks charging the paper-in-oil capacitor are present only at half wave, 60 times per second in the US. In contrast, a full wave rectifier would work on both half waves, showing a 120 Hz ripple. But the oven is built to be as cheap as possible, by saving either three diodes, or a tap in the secondary winding. The transformer has another low voltage winding to light up the filament of the magnetron, which is also the cathode from where the electron are emitted and spun into the multiple LC circuit (in a vacuum). These tuned circuits are made of wavy copper. Of the multiple LC resonant cells inside a magnetron, the antenna output can be connected to any of them; the geometry operating the electrons beam rotation under the influence of a static magnet (at a fixed frequency, equal to the resonance of the water molecules) is a kind of black magic. Keep in mind that a magnetron is one of the very few application where a vacuum tube (the magnetron itself) hasn't been replaced with a semiconductor equivalent. Thank you for the great video!
@ScienceAsylum
Жыл бұрын
I clarify in the pinned comment.
Amazing how a microwave can be so simple, yet so complicated at the same time. Thanks for the good video man!
@ScienceAsylum
Жыл бұрын
Right?! I love it.
Great video as always, and very entertaining rant from ElectroBOOM! Glad you and the scope are ok!
WE NEED MORE OF YOU AND MEHDI
A half wave rectifier DOES NOT waste 1/2 the energy, even when configured as voltage doubler. If it did the 1000W oven will put 1000W into the food and 1000W into the kitchen cabinet starting a fire.
@ScienceAsylum
Жыл бұрын
I've pinned a comment clarifying.
Grear video. For once, this is a video topic I understood completely. If there's one thing one of my circuit classes' professor drilled into us, it was that diodes are not loads.
more collabs with famous youtubers! well on the way to 1mil now Nick. Remember the days when it was just a handful of us and we said you must keep pushing! 😊
I am now thankful that me and my friend never realized the microwave weapon we planned to build from a microwave oven back in the days.
Science Asylum and Electroboom? This can't get any better!
I've been with this channel since it's first debut and I love how he approaches topics. Makes learning feel less formal and fun
@ScienceAsylum
Жыл бұрын
Thanks for the positive feedback 🙂
It has been many a year since I used an oscilloscope, and almost as long since I understood an electronics discussion. Thank you for an excellent video.
That was an excellent video and cleared up a few things I did not fully understand. Would love to see more electronics like this.
When the capacitor is shorted out at 3:10, something DID happen. The audible click was very likely the sound of electric discharge via an arc to one end of the pliers just before contact was made.
ElectroBOOM in the thumbnail + "half-wave rectifier" name card = me bracing myself for the next parts of the video.
the legendary collab i was waiting really for😄😄😄
Hah, nice collab! Did not expect you two to team up, but that's pretty fun. Although i haven't actually watched the video yet, but i just got excited and wanted to comment. Maybe 2023 will finally be the year you'll have 1.000.000 crazies!
Im confused. It seems that half-wave doubler does not waste energy (at least noting near 50%), or i'm missing something?
@eDoc2020
Жыл бұрын
You're not missing anything. Read the pinned comment.
Small nit: that cellphone converter you held up is NOT transformer based. Rather it has a switching power supply. That's why it is so small and light.
@ScienceAsylum
Жыл бұрын
I'll admit, I based that statement on my knowledge of those bulky phone chargers from the 90s. I wasn't aware the design changed.
@rayoflight62
Жыл бұрын
There is a transformer inside, to separate the main from the output. It just doesn't operate at 60 Hz, but at 100 KHz, so it can be very small and convert energy very efficiently...
@keysersmoze
Жыл бұрын
@@ScienceAsylum I just assumed they became switching power supplies from their light weight for their power rating. Pick one up, hey Where did all the Iron and copper go?
@peterdonnelly1074
Жыл бұрын
It still has a transformer, albeit quite a bit smaller
@martinpayne2934
Жыл бұрын
@@keysersmoze The other clues are the high pitched whistling sounds they make, the weird vibration you feel if you run your finger along a metal surface on the device being charged, and the electric shock you get if a single hair on your finger is touching a metal surface on the device being charged!
Thank you so much for this video! Besides explaining the awesome electronics of microwaves, this actually made me understand half-wave rectifiers better. As I had a rough time with electronics in my previous lab course 😅.
@ScienceAsylum
Жыл бұрын
Glad I could help 🙂
I've run into some microwave transformers that do limit current. With a suitable core design you can get it to limit current when for example in short circuit. I thought all were like that. I think energy is not wasted. Energy conservation shall not be violated! Half wave rectification only uses half the cycle and leaves the other half cycle unused. I wonder if the magnetron has something against too continuous power of if that is just a way to save some diodes. A full bridge rectifier takes 4 diodes after all and 4kV (or whatever) rated diodes tend to cost way more than pennies the usual mains diodes cost.
What a great Collab!!!! Lovely 😍
Thanks for the beautiful video ! Learnt something new today !
@ScienceAsylum
Жыл бұрын
My pleasure 🤓
That capacitor still had a significant charge! That loud tick when you shorted it with the pliers was a good arc.
These crazy videos are always amazing and fun! Keep 'em comin'! 😃💯💫💢💖💥
IF you thought Nick was crazy...wow...that ELECTROBOOM guy is off the hook.
It would have been interesting to try a capacitive probe near the transformer. This would have protected you and the DSO, but the amplitude may not have been perfectly accurate. Much of this is used on automobiles for charging batteries or even ignition (spark). Very well done, sir.
@AlexandarHullRichter
Жыл бұрын
I haven't heard of anyone checking batteries with those, since a basic multimeter is usually sufficient, but that type of probe is used to detect ignition timing in cars that have distributors.
Great work man, loveit.
@6:41 I had to laugh. This reminded me of my high school electronics class when I bread boarded a circuit with a zener diode with the polarity backwards.
Love this! Hey can you do a similar video on common Air Fryers? I've been fascinated to learn how it works at this level and see the inside of one!
@NemexiaM
Жыл бұрын
its way simpler than microwave, it just a heating element to heat the air and a fan to direct heated air to food
@Barnaclebeard
Жыл бұрын
It's just a hair drier for your food.
@jazay591
Жыл бұрын
@@Barnaclebeard beat me to it lol
Seeing Mehdi always bring joy... ⚡⚡⚡ The biggest electrician...
Dog gone it! Nick, I needed this video last week! I would have used it as a part of my magnetism and induction unit for my AP Physics 2 class. Great video, next year's students will be the lucky ones.
@ScienceAsylum
Жыл бұрын
Like I said at the beginning of the video, I wouldn't recommend that most people play around with microwave parts. So dangerous.
oh man i don't always watch every video you make but this one was so entertaining!😅
Well, I know the basic principles of the Microwave, but I didn't even knew the circuitry have such drama, thanks for letting me know that. The collaboration with Mehdi @ElectroBOOM is always fun 😅 But funny, we call his name Mahdi, not Mehdi... but don't tell him that 🤣 10:23 Can't wait for this video.
I always have anxiety when someone open the inside of a microwave.
@ScienceAsylum
Жыл бұрын
Understandable reaction.
Congratulations 600K 🎉 onwards & upwards 💪🏻
@ScienceAsylum
Жыл бұрын
Thanks!
Thank you there are several scientific experiments I've been wanting to do and the way you described a microwave means now I can do them as it has all the parts already wired up
@ScienceAsylum
Жыл бұрын
But, remember to heed my danger warning!
@stacyroe619
Жыл бұрын
@@ScienceAsylum oh I absolutely take all the precautions as a side note you ever think of using a electrical equivalent of an overflow valve to prevent overload like a spark gap I got the idea from the Marx generator and a bathtub not at the same time mind you I'm not trying to electrocute myself
5:07 megatron 😂😂😂😂😂😂😂
Hey 👋 nick! Thanks for these wonderful videos.
just both of you together in one video is extremely fantastic ....we love you guys.
Mehdi is doing a lot of consulting this year. Good for him!
Just to add a little detail to the circuit :) It looks like the diode is usually connected between the capacitor and chassis. This allows for an ac current applied to the fillament of the magneton to be DC biased to high voltage (think hot filament electron emission). The electrons dump into the shell of the magnetron, back to ground. A video detailing the magnetron would be awesome! They're ingenious little vacuum tubes :)
@ScienceAsylum
Жыл бұрын
All the big components are grounded to the chassis. I didn't realize there was a sneaky reason for that.
@AlexandarHullRichter
Жыл бұрын
@@ScienceAsylum I was always nervous about letting metal objects touch a microwave casing while it was on (careful not to put a fork or spoon on top of the microwave while waiting for my lunch to cook, for instance). Now I guess have a really good reason for that.
@PlatypusPerspective
Жыл бұрын
@@AlexandarHullRichter The casing of a microwave oven is simply an earthed metal box. There's no difference between it and any other grounded metal surface - if the microwave is next to a refrigerator, there would be no difference between placing a fork on the refrigerator or the operating microwave.
@woll3Y
Жыл бұрын
The "coming soon" explanation of the 2.4 GHz solid state magnetron should also cover why they moved away from the ~900 MHz vacuum tube style. (Running the oven empty creates an impedance mismatch that could start a fire and/or break the glass) Would also be great to see how @The Science Asylum explains the quarter wave choke energy seal that works even if you hang a kitchen towel on the door before you close it.
@PlatypusPerspective
Жыл бұрын
@@woll3Y I've tried to follow the line of your post, but I'm not sure I get what you're saying. Either 900MHz or 2.4GHz are used depending on what will be most effective and practical for the application, more than because of any particular type of technology available. The physical constraints of the wavelength, with the resulting mechanical sizes, and the inevitable difference in load energy absorption and depth of penetration govern the suitable usage. Because of this, 900MHz is usually used in large equipment in commercial and industrial arenas and at high powers, where improper usage could certainly produce spectacular results.
As soon as I heard that pop of the capacitor I knew exactly what happened AND what you smelled. My first job was testing circuit boards to make sure they worked as intended. And whenever something got installed backwards, especially capacitors, it was trouble. After a while I recognized the smell and was able to shut the power off before anything caught on fire or exploded. Cause that happened a few times. Also this was a collab I never knew I needed.
@ScienceAsylum
Жыл бұрын
Smell memory is wild, isn't it?
@ikitclaw7146
Жыл бұрын
@@ScienceAsylum it really is, as the capacitor popped i got the smell of it and stopped the video for a few sec to sniff around me lol
Electro booms slap on the head was hard man is that a red spot ??? 🤣 Educational content for sure and nice volume voice n all 🙏🙏
I appreciate the video, great job
👍A real hazard is the beryllium oxide that is contained in the ceramic insulators in the magnetron. They are no hazard as long as it's not disturbed and does not become airborne. Often people are taking them apart for scrap or to get the magnets and may not know that any breaking grinding or cutting may free the beryllium and cause an incurable respiratory health problem called chronic beryllium disease.
@GannDolph
Жыл бұрын
I actually think they stopped using beryllium insulators in the magnetrons decades ago
A half-wave rectifier doesn't waste half the energy from the cycle, it just doesn't use it.
@ScienceAsylum
Жыл бұрын
I clarify in the pinned comment.
My two favorite Mad KZread Scientists in one video! What a time to be alive! Congrats for the awesome and informative video!
Good you made a model. People were making devices to burn arcing patterns into wood using salvaged microwave transformers and the injuries were pretty bad. Best not to mess with them.