Dude! Thanks for the video! Nice design, simple but does the trick, and would actually be practical if the power went out, you could at least power a lamp, well, y'know, you have! If you wanted true sine wave you could do it the way you describe but you'd probably need an analogue power amp, doing what the motor drivers do, for a sine wave which you'd probably generate with an analogue oscillator as well. But analogue stuff breaks my brain. I just tinker, not got a proper electronics education. There's such a thing as "modified sine wave" which I THINK is just leaving a bit of off-time between the positive and negative pulses, but is surprisingly useful in practice, although again, as you say, not so great with motors. Since square waves have high-frequency harmonics, which don't move the motor but do cause heating in the coils. Also of course if you went with 60Hz you'd have to have much more powerful drive circuits, using a higher frequency means you can get away with sending lots of little bursts of energy instead of fewer, bigger ones. Incidentally that's why power supplies, phone chargers, are so light these days compared to the old linear ones that had a big transformer inside. Instead, they work at high frequency pumping the input voltage into a much smaller transformer. Switch-mode power supplies, PC PSUs are that type. You could do it with a digital to analogue convertor (DAC) though. Have you heard of Arduino? I have a feeling you'd love it. Little single-chip with a CPU, RAM, programmable flash ROM, and lots of peripherals built in, all in the one chip. So you get ADCs and DACs and timers and stuff. Microcontrollers have been around for decades. Speak 'n' Spell had one in the late '70s, but modern ones are more powerful. And the key thing with Arduino, is it's large community and software base. There's software routines to do all sorts of useful stuff, just about anything you could think of. Infra-red remote, RGB smart LEDs, keypads, smart cards... You program them in C, but the IDE you use is helpful and you can start small. Then you have the advantage of learning C, which is also what a lot of software is written in. Including operating systems, C is a low-level language that can control anything it's allowed to get at. There's tons of tutorials for Arduino. And it's open-source, so you can buy an unofficial non-brand-name one for literally a couple of bucks. Programs via USB lead, and that's all you need, also powered through it. Then get a few LEDs and switches and stuff and see what you can do. Maybe some 7-segment LEDs, or LCD displays. Something I enjoy, anyway, and using a microcontroller means you can put your ideas into practice by merely typing rather than having to buy chips and wire them up. Though you get that too! Yeah 1300Hz works the lamp because the LEDs in there are DC anyway, there's a little power supply in the base that converts the mains into something suitable. You ever watch Big Clive's RUclips channel? He's great, covers everything, friendly bloke. I recommend. It's mostly lower-level stuff too, he goes into circuit diagrams but there's none of the theory and maths. An old incandescent light bulb would work with your inverter, or anything that's a resistive load really. Probably a phone charger too since those also just convert mains to DC then chop it up into high frequency and transform it. Maybe try it with an older, cheaper one! Thanks for the video, interesting to see what you've come up with. Never had someone make a video at my request before! Thanks also for indulging me in this rambling post. Assuming you did! Best of luck, mate!
@@jacob_davis You said "analogue to digital" but I know what you meant, anybody would. Glad you're into Arduino, there's really few limits to what you can do. Companies online sell kits that contain a load of various components and input / output stuff to interface with the real world. You get a nice selection for experimenting with. In fact an Arduino's PWM DAC might be useful with your inverter. It isn't a real analogue DAC, it just sends out fast pulses. The wider the pulses, the more current delivered, so that's sort-of analogue. If you smooth out the high frequencies it's an adequate replacement. Apologies if you already knew that. Since it's just on / off pulses though, you might be able to drive your motor driver chips with it, maybe using the inverter gates if one pin of the Arduino can't supply enough current to drive all of them. Then you'd have your transformer being sent a lot of pulses, which it will naturally smooth out, like inductors do. So you might be able to get a 60Hz DAC "sine" wave, that's close enough, thanks to the inductance of the transformer, to actually look like a sine wave. Have you got a scope? Would be fun to try, solving the problem in software, and of course versatile. You could switch it to 50Hz if you ever wanted to. Some Arduino boards can run directly on 12V. They have an onboard regulator, you can supply the 12V to one of it's pins. Before the regulator, not after, of course! I've bought a Pine Watch, which you can program yourself from the operating system up. Not really got into it yet though. There's an existing OS that uses a lot of Python, I suppose I could learn Python. I want to write apps and stuff that connect to my phone and let me do useful stuff. My first smartwatch I got so it could tell me who's calling. With my Bluetooth headphones on, I could take or reject calls without having to touch the phone in my pocket. But of course I need to know who's calling. An app would tell me via a voice, but I thought a watch display would be better. You can get cheap smartwatches that are also phones in their own right! Only 2G though and that's limited more and more as providers drop it, and they really ought to, it's ancient and a waste of radio bandwidth. But you don't have to use the phone part, just as an accessory to your modern phone they're great. They do just about everything! And they're like $10! But for now I must endeavour with my Pine. Thanks for reading again!
Also... you can measure higher voltages with your meter, by dividing them down first. If you had, say, a 9K and a 1K resistor in series, 10K total, you could put a voltage across those. Then measuring just across the 1K would give you a tenth of the voltage. Ohm's law as applied to voltage distribution around a circuit. I'm really not trying to insult your intelligence but be very very careful with 1000V. It's a small transformer but a human heart is sensitive to much less! Be careful with the existing 120V or so too. You could literally die, only takes a moment, so be diligent and disciplined. I don't know that they actually make 9K resistors, and for accuracy you'd measure the *actual* resistance of yours, rather than just going by the label, so you can calculate properly, because you want exactness I'm sure. It would also work with, say just 900 ohms and 100 ohms. But the total resistance determines how much current flows for a particular voltage (again Ohm's law). 1000V / 1000ohms would be 1A which, multiplied by the voltage, is 1000W, which is way way more than your resistors' power rating. In fact using 9K and 1K resistors would give 100mA, which, also x1000V would be 100W. So actually you'll want much higher resistances. Small resistors are usually 1/4W, 250mW. So at 1000V that's 0.25mA. So... 4Megohms I think, in total, at least. So why not 1Megohm and 9Megohm resistors, giving 10M total, at 1000V that's 0.1mA, x1000V = 100mW, which is fine. That's still enough power to kill you though, of course. Maybe practice all this with 9V from a battery first or something. Or else find yourself a bunch of electric heaters...
@@jacob_davis Pardon me rambling on, but I get there in the end! How old are you btw? Seems like your photo avatar thing is a few years old, I was very impressed by a kid who looks 9 making an inverter! But even as a teen it's impressive. Do you learn any of this at school or is it all self-taught and Internet? When I was at school, I'd often be bored. But I had a genuine interest in science, so I just read the textbooks through for something to do. Actually learned better than from the lessons. Where we'd be given an experiment to do, it would inevitably fail for some reason, then the teacher wrote on the board what *should* have happened, for us all to copy down. Dear me! Actually if you misbehaved you'd get shoved into a little cupboard of a room. What they didn't seem to realise was that the room was stuffed with back copies of New Scientist magazine, a respected British magazine a lot like Scientific American. Except not American. So I'd spend an hour or so with all these fantastic magazines reading about science, and learning a load, even though that wasn't the point. But curiosity will teach you much better than most schoolteachers. Although some are encouraging, and love the subject themselves, which really helps. Not that I'm saying misbehave at school. Only if the punishment is more interesting and educational than the lesson.
Dude! Thanks for the video! Nice design, simple but does the trick, and would actually be practical if the power went out, you could at least power a lamp, well, y'know, you have!
If you wanted true sine wave you could do it the way you describe but you'd probably need an analogue power amp, doing what the motor drivers do, for a sine wave which you'd probably generate with an analogue oscillator as well. But analogue stuff breaks my brain. I just tinker, not got a proper electronics education.
There's such a thing as "modified sine wave" which I THINK is just leaving a bit of off-time between the positive and negative pulses, but is surprisingly useful in practice, although again, as you say, not so great with motors. Since square waves have high-frequency harmonics, which don't move the motor but do cause heating in the coils. Also of course if you went with 60Hz you'd have to have much more powerful drive circuits, using a higher frequency means you can get away with sending lots of little bursts of energy instead of fewer, bigger ones. Incidentally that's why power supplies, phone chargers, are so light these days compared to the old linear ones that had a big transformer inside. Instead, they work at high frequency pumping the input voltage into a much smaller transformer. Switch-mode power supplies, PC PSUs are that type.
You could do it with a digital to analogue convertor (DAC) though. Have you heard of Arduino? I have a feeling you'd love it. Little single-chip with a CPU, RAM, programmable flash ROM, and lots of peripherals built in, all in the one chip. So you get ADCs and DACs and timers and stuff. Microcontrollers have been around for decades. Speak 'n' Spell had one in the late '70s, but modern ones are more powerful. And the key thing with Arduino, is it's large community and software base. There's software routines to do all sorts of useful stuff, just about anything you could think of. Infra-red remote, RGB smart LEDs, keypads, smart cards...
You program them in C, but the IDE you use is helpful and you can start small. Then you have the advantage of learning C, which is also what a lot of software is written in. Including operating systems, C is a low-level language that can control anything it's allowed to get at. There's tons of tutorials for Arduino. And it's open-source, so you can buy an unofficial non-brand-name one for literally a couple of bucks. Programs via USB lead, and that's all you need, also powered through it.
Then get a few LEDs and switches and stuff and see what you can do. Maybe some 7-segment LEDs, or LCD displays. Something I enjoy, anyway, and using a microcontroller means you can put your ideas into practice by merely typing rather than having to buy chips and wire them up. Though you get that too!
Yeah 1300Hz works the lamp because the LEDs in there are DC anyway, there's a little power supply in the base that converts the mains into something suitable. You ever watch Big Clive's RUclips channel? He's great, covers everything, friendly bloke. I recommend. It's mostly lower-level stuff too, he goes into circuit diagrams but there's none of the theory and maths. An old incandescent light bulb would work with your inverter, or anything that's a resistive load really. Probably a phone charger too since those also just convert mains to DC then chop it up into high frequency and transform it. Maybe try it with an older, cheaper one!
Thanks for the video, interesting to see what you've come up with. Never had someone make a video at my request before! Thanks also for indulging me in this rambling post. Assuming you did! Best of luck, mate!
yes the arduino is fun to use
you're right, digital to analog converter is the right term for what i was trying to explain
@@jacob_davis You said "analogue to digital" but I know what you meant, anybody would. Glad you're into Arduino, there's really few limits to what you can do. Companies online sell kits that contain a load of various components and input / output stuff to interface with the real world. You get a nice selection for experimenting with. In fact an Arduino's PWM DAC might be useful with your inverter.
It isn't a real analogue DAC, it just sends out fast pulses. The wider the pulses, the more current delivered, so that's sort-of analogue. If you smooth out the high frequencies it's an adequate replacement. Apologies if you already knew that. Since it's just on / off pulses though, you might be able to drive your motor driver chips with it, maybe using the inverter gates if one pin of the Arduino can't supply enough current to drive all of them. Then you'd have your transformer being sent a lot of pulses, which it will naturally smooth out, like inductors do. So you might be able to get a 60Hz DAC "sine" wave, that's close enough, thanks to the inductance of the transformer, to actually look like a sine wave. Have you got a scope?
Would be fun to try, solving the problem in software, and of course versatile. You could switch it to 50Hz if you ever wanted to. Some Arduino boards can run directly on 12V. They have an onboard regulator, you can supply the 12V to one of it's pins. Before the regulator, not after, of course!
I've bought a Pine Watch, which you can program yourself from the operating system up. Not really got into it yet though. There's an existing OS that uses a lot of Python, I suppose I could learn Python. I want to write apps and stuff that connect to my phone and let me do useful stuff. My first smartwatch I got so it could tell me who's calling. With my Bluetooth headphones on, I could take or reject calls without having to touch the phone in my pocket. But of course I need to know who's calling. An app would tell me via a voice, but I thought a watch display would be better.
You can get cheap smartwatches that are also phones in their own right! Only 2G though and that's limited more and more as providers drop it, and they really ought to, it's ancient and a waste of radio bandwidth. But you don't have to use the phone part, just as an accessory to your modern phone they're great. They do just about everything! And they're like $10!
But for now I must endeavour with my Pine. Thanks for reading again!
Also... you can measure higher voltages with your meter, by dividing them down first. If you had, say, a 9K and a 1K resistor in series, 10K total, you could put a voltage across those. Then measuring just across the 1K would give you a tenth of the voltage. Ohm's law as applied to voltage distribution around a circuit.
I'm really not trying to insult your intelligence but be very very careful with 1000V. It's a small transformer but a human heart is sensitive to much less! Be careful with the existing 120V or so too. You could literally die, only takes a moment, so be diligent and disciplined.
I don't know that they actually make 9K resistors, and for accuracy you'd measure the *actual* resistance of yours, rather than just going by the label, so you can calculate properly, because you want exactness I'm sure.
It would also work with, say just 900 ohms and 100 ohms. But the total resistance determines how much current flows for a particular voltage (again Ohm's law). 1000V / 1000ohms would be 1A which, multiplied by the voltage, is 1000W, which is way way more than your resistors' power rating. In fact using 9K and 1K resistors would give 100mA, which, also x1000V would be 100W.
So actually you'll want much higher resistances. Small resistors are usually 1/4W, 250mW. So at 1000V that's 0.25mA. So... 4Megohms I think, in total, at least. So why not 1Megohm and 9Megohm resistors, giving 10M total, at 1000V that's 0.1mA, x1000V = 100mW, which is fine. That's still enough power to kill you though, of course. Maybe practice all this with 9V from a battery first or something.
Or else find yourself a bunch of electric heaters...
great idea! i should try that
@@jacob_davis Pardon me rambling on, but I get there in the end!
How old are you btw? Seems like your photo avatar thing is a few years old, I was very impressed by a kid who looks 9 making an inverter! But even as a teen it's impressive. Do you learn any of this at school or is it all self-taught and Internet?
When I was at school, I'd often be bored. But I had a genuine interest in science, so I just read the textbooks through for something to do. Actually learned better than from the lessons. Where we'd be given an experiment to do, it would inevitably fail for some reason, then the teacher wrote on the board what *should* have happened, for us all to copy down. Dear me!
Actually if you misbehaved you'd get shoved into a little cupboard of a room. What they didn't seem to realise was that the room was stuffed with back copies of New Scientist magazine, a respected British magazine a lot like Scientific American. Except not American. So I'd spend an hour or so with all these fantastic magazines reading about science, and learning a load, even though that wasn't the point. But curiosity will teach you much better than most schoolteachers. Although some are encouraging, and love the subject themselves, which really helps.
Not that I'm saying misbehave at school. Only if the punishment is more interesting and educational than the lesson.