Arduino MIDI In circuit

Hello fellow Arduino users!

I want to build a circuit to receive MIDI from my keyboard, but I was not able to get en optoisolator of any kind (Thanks, third world countries...). I do have some strong LEDs, heatshrink plastic and some photoresistors.

Could I make a MIDI In circuit using a homemade optoisolator?

Don´t fail me now community :D :D

Well you can make an opto isolators that way but the problem with MIDI is the speed. It is a serial signal of 31250 bits per second. This is too fast for most opto isolators chips, only the fastest will work.

So while you can make your own I doubt if you can get it to react correctly.