Daily science thread

daily science thread.
guess what i'm trying to do here Sup Forums

make some kind of midi controller

darn, that was fast

what gave it away,

the DIN connectors ?
the usb/midi cable ?
the scope trace ?

Well the midi cable to be honest, but I'm a music fag so I guessed based on that alone.

I wish I had the electronics engineering prowess to build something like that though.

Cool shit user.

What exactly are you making or using it for?

it's all still pretty simple, but fun stuff

i needed a MIDI to TTL (transistor-transistor-logic eg. 5V) level converter so i could feed it into a standard UART (serial port) on a micro controller.

had to tweak resistor values for different optocouplers to get nice sharp edges

it was to mod an old Agfa Arcus II scanner to play from live MIDI.

Sound is created by running the stepper motors at the note frequency, this one had 2 channels.

was a pretty fun project

You lost me here

But I got this part. That's fucking cool man

Oh do we feel smart tonight OP?

Ok, try to guess what my two circuits do.

cool thanks, it was used in a a theatre play so it was pretty loud

some kind of dimmer ?

chopper?

ITT: Post ur science gear

...

is fixing fancy lab equipment all you do ?

I like buying stuff on fleabay that is marked -not tested, as is... and fixing it :)

Yeah, the upper citcuit is an ~230V/=5V converter to power a microcontroller.
This mc controls the optocoupler in the second circuit which controlls a triac.

looks like a pretty solid design. nice work user.

nice, i would probably have gotten bored with it before building up such a collection, lel

where are you doing zero-cross detection ?

oh wait triac

It's not on the pic. I measure the ~9V side of the transformator and simply use the adc of the microcontroller.

One problem I have is to find useful projects. It's fun to do this stuff but i wish i could build something usefull which is worth the time and money and which I can not just buy on amazon.

there's always stuff around that needs automating user, get back to work

get attention

Duh. You're whiting your screen so you can see where to clean it.