Archive for the ‘Optocoupler’ Category

Accordion Playing Midi Under 100$

Tuesday, January 18th, 2011

Amazing Accordion sending MIDI under 100$ (instead of 6,699.00$), as [Dmitry Yegorenkov] shares on Arduino Forum and published on GitHub.

I like to play accordion & have a dog. People say dogs are singing with squeezeboxes and some people find it funny. Not for me. I know that my pet hears note harmonics much better then me & suffers from high pitches very much. I could not really practice at home just because of humanennes. That sucks. I like to play accordion. Programmers see cycle here. Let’s get out.

It plays to headphones, produces MIDI output, etc. etc. It costs $6,699.00 on e-bay (buy now offer) on November 17, 2010. In the US I can buy Peugeot Partner for the same price. In Ukraine where i live both are 1/2 times more expensive. For that money i’ll get beautiful device to practice at home and no service centers available within 400Km radius. Weird.

Code and Schematics-ready on [Accordion Mega's Github]

Optocoupler demystified

Wednesday, September 22nd, 2010

[tronixstuff], who has wrote a ton of arduino tutorials, has posted a detailed guide to one of the most useful electronic components, used to trigger many low-voltage circuits: the Optocoupler.

It is a small device that allows the transmission of a signal between parts of a circuit while keeping those two parts electrically isolated. How is this so? Inside our typical optocoupler are two things – an LED and a phototransistor. When a current runs through the LED, it switches on  - at which point the phototransitor detects the light and allows another current to flow through it. And then when the LED is off, current cannot flow through the phototransistor. All the while the two currents are completely electrically isolated (when operated within their stated parameters!)

via [TronixStuff]