Voltage waveform modification

>>1052096

>I want to turn a $13.75 Chinese AC speed controller into a variable power supply

For what? The output wouldn't be isolated so it would be kinda dangerous.

>>1052096
A capacitor

Not really sure though, but interested in why it wouldn't work/not be very optimal.

>>1052101
Worry not, I bought a bank of circuit breakers and wired up any metal casing to earth/ground so everything is mostly safe. If this is not what you meant by this statement, please clarify.

>>1052107
>and wired up any metal casing to earth/ground so everything is mostly safe

Either way if something goes wrong in your circuit you could get mains at the output. Rectifying and filtering a triac output is really not a good way to make a variable power supply.

Do you need this for a specific purpose or do you just want a general purpose bench PSU?

>>1052110
General purpose, I don't have much to hook it up to anyway, just for personal experimentation. The breakers are the fastest tripping ones out there, and the speed controller has fuses in it too, so I probably won't end up electrocuting myself, just components. It's not like 220VAC mains would be much more dangerous than 10VAC at the same power anyways.

>>1052114

The breakers won't trip if you get electrocuted, they would just see you as another load.

> It's not like 220VAC mains would be much more dangerous than 10VAC at the same power anyways.

It's actually infinitely more dangerous. Ohm's law.

Theoretically you could stick a bunch of filter caps after a rectifier but there would be loads of ripple as soon as you pulled any kind of current. Overall it would be an extremely dangerous and shitty PSU. If you're on a tight budget get an ATX power supply from some old computer and hook up a cheap DC-DC converter from ebay to it. It would be safe and you'd even have neat features like current limiting.

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Hi!
I'm working to a simple didactic project about sampling.
I'm looking for a one channel 8 bit parallel adc to be clocked by a simple square wave oscillator made with a ne555 or something like.

The idea is to feed the system with a sine wave and show the signal in the different stages, i mean the original sine, the step wave and the result with an oscilloscopede, maybe the digitar form with some led. I really don't want an anti aliasing filter inside the dac, because I want to show the issues of an incorrect sample.

I need a DIP one, and maybe not too expensive, less than 5 $ would be nice.
Any suggestion?

>>1052114
Your body has too much resistance for the breakers and fuses to trip, so you'll probably die.

>>1052115
As far as I assume, the amount of current that flows through a person when they touch a wall outlet isn't likely to be in the same order of magnitude as the current that kills a person, and since I=V/R, if V is 10 or 20 times less, the chance of you dying isn't changed by much, am I right? Of course, a 12V car battery literally debunks this theory huh. Is it true that AC is more dangerous than DC?

"If more than 100mA makes it through your body, you're probably dead." Apparently a 9V battery killed a guy who stabbed both thumbs with multimeter probes, so I guess skin is a pretty good insulator against DC. Resistance with skin approaches 100kΩ, but broken skin can reduce it to 1kΩ. Either way, the 9V battery in the multimeter probably shouldn't have killed the man, it had up to 1/10 the supposed lethal current. Can post source if wanted.

>>1052127
>>1052115
Could you current limit to below 1mA? because I wouldn't like to let through much more than that if I touched the wrong contacts.

>>1052124
If you are unclear about this stuff, don't play with mains.

>>1052129
You could stick some 1mA fast blow fuses in place but that would also render your PSU useless.

I've already built the thing, I'm using it as a temperature controller for my 80W soldering iron at the moment, but the non-sine wave makes fluorescent lights hum unhealthily, and the DC outputs are mostly useless.

>>1052124

>Of course, a 12V car battery literally debunks this theory huh

AC passes through human skin much more easily due to our capacitive nature. I won't get into details but let's just keep it at this >>1052131

>>1052139
Cool, thanks for that clarification. So in actuality 12VAC and 230VAC are both more or less about deadly. RIP Edison.