Filtering Square Waves to Sine Waves - Simply Put

[@simplyput2796]

New version of this video, with a better circuit and its diagram, if you're interested: kzbin.info/www/bejne/n6bTqYGIisyNq80

[@Mark_KE8YCV]

Dude. Thank you. You've clearly got that rare gift for simplifying the complex. You are a living breathing impedance matching network ;-)

[@plasmaguy5]

Sir I have never heard a better taught class on electronics as you. Your Awesome.

[@GraphicManInnovations]

this is a very rare high quality teaching / video, thank you

[@effigymusic179]

You are a savior! Been tryna synthesize sine waves on a pc speaker using templeos and this is one of the rare gems of resources that has actually been helpful🙏 Thank you, Godspeed

[@malingeorgiev2962]

Low pass RC filter work best when signal at main frequency is reduced with 3 dB. This mean two times. So after first stage signal to be 2,5Vpp, after second 1,25 Vpp and on exit 0,67 Vpp. Next transistor stage will need to have amplification 8 times to restore signal to 5 Vpp. As well I recommend to reduce values of condensers by two. 100 nF , 47nf and 22nf. Like this will be easier to adjust the filter.

[@stewatson3922]

An excellent demonstration and presentation AND no annoying adverts every 20 seconds, thank you

[@willfoley25]

Quite honestly the most informative and easy to understand class on filters I have ever had!!!!

[@klmkt4339]

Also I

[@profrobinson]

Like so much your explanations and your english speaking is very clean.

[@jeremysender]

Your videos are great, I have self taught myself to an intermediate level just using your videos. You should know that you have really helped someone out and I am extremely appreciative to your great videos where you reason and think logically about why the circuits behave the way they do.

[@nazgullinux6601]

If you used his videos, you didn't teach yourself. HE taught you. You're no autodidact.

[@w3w3w3]

I hope you doing well buddy. I joined your discord and seen you message... you seemed like a super cool guy very interesting videos also. Get well soon yea 👍

[@simplyput2796]

Small correction: They're 2-megaohm potentiometers, not 500-kiloohm (kilohm?). A rather striking difference!

[@ovalwingnut]

Damn! Now that was interesting. A "ah-ha" moment for me. Thank you 👍😁 Subbed.

[@sandrofilho7063]

Thats the best Class i've ever had!! Thankss

[@robertmonroe9728]

Dwarves from fantasy world usually doing mining and other staff. Modern dwarves doing electronics engineering. Nice!

[@3deeguy]

Nice work. I've been thinking about a variable frequency drive for a couple of years. Creating a 60 Hz sine wave is a great tutorial.

[@T2D.SteveArcs]

You would use pwm at a carrier in the khz driving a full-bridge inverter then filter the output with an LC filter to create your low frequency smooth sinewave 👍

[@Youssef-t3p]

Thank you for the easy way to explain. You deserve million subscribers

[@Enigma758]

I just discovered your channel and I really like your presentation. Subscribed!

[@romanmorales3325]

Very good and highly appreciate your efforts ❤

[@GeorgeWMays]

Excellent super cool video. I enjoyed this greatly. Thank you; it's appreciated.

[@bulla8631]

what kind of capacitor it need to used to do this I means a 240volts or 400volts what it called this capacitor

[@keithking1985]

Your very good and clear at explaining things. I'm going to subscribe and I hope you keep the channel going👍👍

[@Warsel]

extremely useful video, made me understand filters a lot better. thanks

[@gsansoucie]

Man your videos have a way of just clicking for me. I’ve just assembled a QRP Labs signal generator and wanted to produce a sine wave. The trimmer pots idea is brilliant. My square wave output has some overshoot and ringing, it will be interesting to see what happens to it through this filter network. Onto your updated version of this video.

[@billiemfan]

That was awesome! Thanks so much for your willingness to share and teach.

[@victoryfirst2878]

I like your down in the weeds method of this subject matter. Thanks

[@FractalIND]

u are the best, i understood everything from you

[@nayt33z]

Did noone else notice the huge hole in the headset? amazing. awesome info though. you explained it so well.

[@silverXnoise]

Thanks, this was really well explained. If you’d prefer not to look like you’re working in Rasputin’s call center, consider a shotgun mic and a Zoom H4 (or something similar). Easy to use/setup and sounds great. If, on the other hand, it’s all part of your jam, then please disregard that-you do you, boo.

[@hillbillylocksport5547]

Man you explained that first part better than I've heard it ever explained before...

[@MrWebsie]

Hope you are ok buddy, it been a long time since you posted, this is some of the best content I’ve ever watched. It would be amazing to see new videos.

[@Userx29]

Very important. Thank you

[@BrentLeVasseur]

Brilliant tutorial and demonstration.

[@dbagnis]

Wow!!! Amazing video!!!..Congratulations and thank you very much.

[@marklll8368]

do you have any video on converting cheap modified inverter to pure sine wave? or if possible is it worth it? mainly asking because modified inverter is much much cheaper than pure sine wave inverter, thanks

[@mendebil]

So helpful. As opposed to 15 other videos on this topic from so called "pros" in the field.

[@patrickjdarrow]

Wish I found this my junior year. So good!

[@sadeghmollaii9873]

I like that smooooooth wave @ 19:14.

[@dominicafonso]

Is there any free software that can be used to perform these experiments including the signal output display?

[@nortenhardenberg1598]

LOVE YOUR HAIR AND EXPLANATION. WHAT IS BETTER TO USE IN HIGH FREQUENCIES; SINE OR SQUAREWAVE TO INDUCE HIGH POWER APLICATIONS?

[@G0USL]

Great demonstration Thanks

[@hiddenworldforge374]

Could I use this concept to turn 240v 60hz ~100 amps of square wave AC to a smoother triangular or at least a smoother modified square wave form AC? I have a DC generator I want to use as a 1ph AC generator. I can make a rotary inverter easily, but my AC motors wouldn't appreciate the harsh square wave power a rotary brushed inverter would create

[@simonowen488]

Hope you're OK, and hope to hear/see from you sgain.

[@nithikasandinu5843]

Content is amazing⚡👍. Please consider fixing the sound problem. High freq. Sounds (s,c) are too loud

[@MrLESRAJ]

Excellent video, thank you sir.

[@junieserrano9113]

Thank you for your Very imformative video !

[@junieserrano9113]

Can you make a video regarding the the flow of current in air-conditioning mother board inverter ?thanks in advance!

[@mikejones-vd3fg]

Very cool, always wondered how capacitors worked in guitar amplifiers/effects pedals to shape the tone, this pretty much explains it. Although there you want a funny shaped wave because they sound good, well depending on your preferance. Theres a guitar pickup company - fishman who makes these new pickups , everyone says sound HD in comparison to what we've had so far. I wonder if they're just giving a better signal so all the filtering thats amps do doesnt affect it as much. Improving the source somehow so we have less loss of information and a better, clearer soundas a result. Because it seems to me that all these capacitors take soemthing away, which is fine if you have lots of bad stuff to take away, but why not just improve the source so theres less filtering needed, which i understand isnt always possible and why this video exists and is very cool. Turning squares into hip smooth waves ? ... magic.

[@ronamo111]

I have a predator gas generator that puts out a modified sign wave if you could build a unit that I could plug in and change it to a pure sign wave I would buy one , you could start a little business out of it, especially if it was not to expensive.

[@fredbecker607]

That is what I am looking for too.

[@Stefan_trekkie]

Some time ago i galaxy far away (Europe) i was doing that and measuring with soviet made crt scope. The interesting part was to convert the sine back to sw. The 3rd thing was to offset it to negative and positive

[@merlepatterson]

Would like to have seen an example for a higher power system, like a 3kw modified square wave inverter which is smoothed out to pure sine wave.

[@southernexposure123]

Thank you very much.

[@Punblogs]

Thank you, sir

[@mmarqueaux1927]

Why don't you turn on the FFT on your scope. You might see the harmonics dropping off as you bring the corner frequency down.

[@prateekchowdhury3337]

22 minutes...... Eyes were only on screen.... Wonderful explanation.

[@vincentrobinette1507]

You might try a band pass filter, where a capacitor is connected in series with the resistor, the other end through another identical capacitor to ground. Tune the variable resistor to get the time constant necessary for the frequency of the square wave. Fewer elements, and, preserve even a greater percentage of the amplitude of the square wave generator. Capacitor-resistor-capacitor. Measure across the capacitor connected to ground. Not only will it be much more efficient, but, i'll bet you'll get even a more convincing sine wave. In fact, I think I'll turn on my oscilloscope right now!

[@simplyput2796]

Sounds like a great idea for a future video. I'll make a note.

[@vincentrobinette1507]

@@simplyput2796 I goofed up! in that series, a resistor needs to be placed between the second capacitor and ground. that becomes the hi pass filter. I did fire up my scope, and while my circuit did create a roll off on high and low, your circuit actually worked better, for taking both edges off the square wave. I also ended up with 1/3 amplitude.

[@tijmeng8550]

Very cool, a question, is there a 90 degrees phaseshift from input to output? 21:26

[@ernestonpurpose3293]

Comic Book Sore Guy does Electronics...I love It.

[@faramoftae]

Oh thank you! Simply Put indeed.

[@michaeld9682]

You do a great job explaining

[@TRAVELWP]

Excellent video ! I learned much !

[@ChuckMcKay]

What is the effect of frequency on the sine wave, Simply Put? If you ran a 1KHz signal through your low pass filter, what would it look like?

[@ahmadal-tarabeen9253]

Well done

[@alphabeets]

I love your videos but why do you have an edit between every sentence?

[@sahraouiwalid9144]

i wish you all the best !

[@mkepler5861]

excellent video!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[@hermance]

Velvety voiced man sending signals at me through the internet. My brain is officially aroused. But just cut it out with the jump cuts please. I think youtube has matured enough to handle long form sentences (Especially in educational contexts). It also means less editing for you, so lower content creation resistance at the input = higher content current at the output and lower chance of burning the whole circuit. The world need your input my duderino. With that said, you just earned yourself a sub. I'll be following this project along. Thanks.

[@simplyput2796]

I understand how the jump-cuts can be annoying, but over the months I've been learning how to do a channel like this and building my "set", I'm faced with the realization that I have to please myself before I can try to please anyone else. My normal speech pattern is filled with gaps like the stereotypical William Shatner, plus I'm annoyed by hearing myself breathe between speaking. I originally tried to edit this manually and you're right: The amount of work is absurd and unsustainable. So...I just wrote my own video editor and it actually does the cuts automatically, and I just have to go in and "clean it up a bit". I absolutely have tried to just do "normal" cuts, and I genuinely just cannot stand how I sound. I hope you can put up with my eccentricity on this, because I have to put out a product I can be proud of and enjoy watching myself, even if it doesn't appeal to everyone.

[@hermance]

@@simplyput2796 I totally respect that. I would rather listen to original music from an uncompromising artist than a crowd-pleasing one. I might have rushed to comment there also. I hadn't noticed the wealth of content you aleady put out. I'm quite new to circuit analysis and component level electronics so, much of your content is still out of my reach but your structured and detailed presentation of fundamentals are exactly what I was looking for. (the understated comedy also hits the spot pretty well). Also, watching this inspired me to try and build a pre-amp for a midi controller keyboard I have. What other video of yours would you suggest could enlighten me on the subject ? For your auto-editor (first this is amazing please cash in on this. There's probably a substential market for this from fellow youtubers) may I suggest offsetting the cut a couple ms left or right ? Anyway, you've made it to my list of reference people on the subject along with EEV blog. Congratz. And thank you.

[@simplyput2796]

Regarding the amplification, and keeping strongly in mind that I am learning as I go (making EEVBlog, an actual electrical engineer, a better reference), from my research thus far I'd say that the amplifier I've already shown off is the way to go for absolute 100% best sound reproduction if you have no restrictions on power usage (meaning you can plug it into the wall and it doesn't need to preserve battery life) and you can afford more expensive components (power transistors and resistors). The other types of amplifiers that I have seen are all designed for reducing power consumption at the expense of quality. I apologize for not getting out more videos, such as about the other types of amplifier: It really is due entirely to my personal life and me being garbage at time management. I'm working on it, I swear. For the editor, I'm not sure there would be a market for it, because in all the time I have put out videos here, regarding comments here on the videos and also talking to my Discord people, as well as watching the few other videos on KZbin I've found with similar editing, I have never once seen anyone praise the style: Everyone seems to either hate it or not care. Similar to the brick-wall audio normalizer I wrote that I use when I do livestreaming: My audience tolerates it, but I've never been praised, only ever gotten comments about how it destroys dynamic range. As for offsetting the cut, are you saying you just wish the cuts weren't as sharp, with a little bit more of a pause between them? That's definitely something I can easily tweak.

[@hermance]

​@@simplyput2796 Yes for the offsetting that is exactly what I'm saying. I'm curious, what criteria are you using in your code to make a cut ? And how do you run that code ? Is it a pluggin for your editing software or an .exe or something else ? I think you might have a rough implementation of a great idea. I can imagine daily/lifestyle vloggers (as much as I dislike the format) saving tons of time with this. There's loads of high content output, average to low production quality youtubers, (no offense of course, different style and purpose) that upload with edits no better than what you already have. If they could have an auto-edited first draft with a full backup you could humm.... you could be a rich man my dude. Of course, going after this crowd means you would need a solid UI and customizable delays and threashold levels for the cut based on whatever criteria you're using. (e.i: if silence for x seconds make cut. With a user variable x) Sorry now I'm rambling. I can see on the other hand that focusing on that would take your attention away from projects of much greater interest to you. And having sensed a high degree of integrity and self-determination in regards to your work, from your first response, I can understand not wanting to streach your attention so thin on secondary projects. Especially, beeing one of us garbage brothers from the time managment bureau bin Yet again, If fortune strikes your back with this idea, feel free to through a couple bucks my way.

[@simplyput2796]

It's a program written entirely from scratch by me, so yes it does have a super-simple UI that just "gets the job done". The way it works is actually pretty simple: I move my cursor along the audio timeline until I come to a part that has a gap and a small amount of noise (such as breathing) that I want to cut, and press a button. It searches a certain amount of time forward and back of the cursor, takes the maximum audio magnitude in that slice, and then cuts forward and back as far as it can until it reaches audio that's louder. Then, it backs away from the louder audio by a certain margin, and makes a cut. Then I press another button, and it goes through the entire remaining audio forward and finds every other area that is also at or below the "cut" audio level that is a certain minimum length (so it doesn't try to make a cut between every word or something). From there, I just hit "play" and listen. It's really nice for editing out vocal flubs and such, because instead of having to actually cut a part out, I just press a button and it just deletes everything between the two adjacent cuts. So my "time spent actually editing" comes out to be barely a couple of minutes longer than the final video ends up being. The audio normalizer uses the EBU R128 standard for measuring "perceived volume" and a moving 400ms window to put the final audio right near -23db (the BBC recommendation) which brings up my low audio if I mumble and caps off my high audio if I get too excited. I could use a much better implementation of that because I have the entire audio track to work with at once, but I'm lazy so I just use the same code for my KZbin stuff that I do for my livestreaming. I doubt I would ever bother to make these into real programs just because I'd never really manage to get around to it, but at some point I ought to at least throw the code up somewhere so somebody else could. I haven't done anything actually interesting, though: My code isn't complex or particularly novel. It's just that nobody else simply has bothered to ever do this (which reinforces my idea that, while it's an untapped market, it's also not an in-demand market). But hey, who knows.

[@m.fadhiilhaekal7693]

This is awesome

[@odanegordon5463]

You stated that the entire circuit is energy inefficient, what would make it energy efficient?

[@JohnDuthie]

Could I try this with the Espotek labrador? Probably not right?

[@davidjackson2115]

Exellant. Ive been comtemplating similar sort of thing. But i figured you dont need an amp - just the signal for transistor to switch but have that transistor switching 10khz- 150khz etc... to put through ferite core step up for 12v to 230v {in my case - but Im not there yet so concept might be wrong. I like yr thinking. Must also be sick of the throw away society and better to have yr own product you can fix.

[@MrHmm-cv6gs]

I dont know how to thank you sir😌

[@anthonymiller4703]

that was excellent, thanks!

[@JDPavon]

One question, what's the value of the safety resistor..

[@simplyput2796]

It just depends on whatever voltage the signal is and what is the maximum current you want coming from your signal source. Just use your standard V=I*R and P=V*I for wherever it is in your circuit.

[@keithking1985]

ya know how you said ya use higher to lower cap size at the beginning of a low pass filter,, would you use lower to higher on a high pass then????

[@ronaldjacobs8561]

If I am interested in smoothing out modified square waves from an inverter, may I replace the resistors with inductors?

[@noneyabusiness969]

yes, that would be called an LC low pass filter. L=variable for inductance and C=variable for capacitance. the inductive elements in the filter must be rated for roughly 2x the current to be drawn, and the capacitors must be rated about 2x the applied voltage. I don't want to go too far down the rabbit hole, as the theory and practical circuit design gets pretty complex, so I recommend you look up a part called, "ac common mode noise filter" These have a pre built low pass design, and are considerably easier to use....👍

[@ArkhamDelta]

You said that a sine wave can be done from any type of wave so, can I get a sine wave from a triangular wave?

[@simplyput2796]

Literally any type of wave, yep! Every single waveform that exists, no matter how complex, is a combination of waves of different frequencies, and the lower the frequency, the bigger part of the overall wave it'll be. I'm planning on doing a new version of this video in the near-ish future with my newfound knowledge of op-amps, but basically, you can take any wave (other than just plain DC, of course; it has to be some sort of up-and-down wave) and keep passing it through low-pass filters and amplifiers to eventually get a sine wave.

[@MyGreggory]

Hi can you make drawings a bit bigger I can't see

[@victoryfirst2878]

Do anyone make a small board or board and chip set to make a true sine wave ?? What is the range of a sine wave to be considered accurate ???? Thanks Simply Put too. Peace

[@Dc_tech386]

So you are saying if I make a inverters and need sine wave all I need is capacitor and trimmer to get perfect ac

[@longbeachboy57]

Where have you been all my life???

[@JonathanVaucher]

I'm a bit of a noob, but will the smoothness of the sine wave be affected by an increasingly higher current load ? Let's say I want to convert my 1100W modified square wave inverter to a sine wave. Can I use your method ?

[@acquireelectricity1458]

Hi, does the same setup of filters change the shape of the wave if the frequency changes? I am planning to make a small synthesizer with 555 timer and I want to hear nice sinewave.

[@garfield4863]

Can you apply this to a guitar pedal? Take the signal from the guitar and make it into a sine wave?

[@simplyput2796]

I don't know how a guitar pedal is structured internally, but if it is a variable resistance, then yes. If your pedal is powered and is putting out a voltage, you'll need to use an ADC, or an analog pin (which is connected to an ADC on the microcontroller).

[@diywoodworkingjourney5010]

Thank you

[@michaeld9682]

After the op amp stage, could this be used as an inverter to run an a/c fan (or such low amp device)

[@simplyput2796]

It would be better to look up some circuit diagrams for actual inverters. I plan to do videos on that topic, but I haven't yet, and you'll be better off with a purpose-built circuit.

[@anastasiamor3582]

Great video, how can I calculate the R and C values without variable resistors? I want to achieve a specific frequency

[@simplyput2796]

Filtering doesn't change the frequency, just the amplitude and shape. The original square wave determines the frequency. (I have a newer video on this topic. You should watch it instead. It's linked in this video.)

[@ahmaddurrah9442]

hi how can i change 2000w square signal into sine wave...or what is the valuse of R & C

[@noneyabusiness969]

An L/C (Inductor/Capacitor) low pass filter is more commonly used when currents are required to be above a couple hundred milli-amps. Think low pass crossover for speaker systems.

[@Coolgiy67]

Using this 3 stage low pass filter turns my 220v square wave into 7v sine lol, I cant use this

[@38huzaif76]

I want to filter a square wave of 50 hz frequency 12 to-12 Vpp .... Can anyone plz guide me

[@royshashibrock3990]

RC networks cannot - and will not ever - give a true sine wave. Anyone who understands the rotational basis for a sine wave knows that a resistor is a linear component, whereas capacitors and inductors are not. Both of the later are required for a true sine wave...period.

[@nickadams2361]

Hypno toad brought me here

[@oibacbeo9285]

Xin chào bạn có thể giúp mình một vấn đề được không.

[@qadoosi09]

How to convert 50 hz 380 V three phase AC square Wave Voltage to Pure Sine wave

[@youssefdirani]

The pro will say it, but many stages of low pass filters maybe ?

[@klmkt4339]

Beard bro. I discovered you today. I will scan you from ear to ear.. meanwhile put some audio amplifier video

[@areusmartinez8343]

🙌🏼

[@youssefdirani]

Super interesting

[@misterbonzoid5623]

Turn up this preset; not capacitor.

[@sunuk1915]

Who's filled the power losses!

[@Midaent]

hi, please how can i reach you ?.

[@simplyput2796]

For short questions, the comments section here is a good place. For longer discussions, Discord (linked in the description) is much easier.

[@keithking1985]

@@simplyput2796 is discord a website or something??? I don't use social media ya see so I'm not informed about the different ways to chat with like minded folks. Please could you message back. Thanks.