MIDI Interface Business Card PCB

If you show off your abilities or wares at an industry event— Maker Faire, or similar conference — you likely bring a bunch of business cards to hand out. While cheap and effective if someone wants to make contact, all too often they’re forgotten in a potential contact’s business-prize bag. On the other hand, enterprising hackers have been making business cards out of PCBs, a great way to get noticed for more than a few hundred milliseconds. As Tim Alex Jacobs (aka “Mitxela”) points out, however, they’re mostly pretty useless after the novelty wears off.

Jacobs, however, decided to create something that both functions as a business card and is actually useful. To this end he devised the StyloCard, a Stylophone MIDI interface printed on a circuit board the size of a business card. In order to make this ultra-compact and cheap enough to hand out, he used an ATtiny85 chip as the processor, and a series of resistors to allow it to tell between 20 notes with two analog inputs. Cleverly, the board is made 1mm thin, with a tab that breaks off to double the thickness of the USB port section as an interface.

The device functions with two crocodile (or alligator) clips, one which stays attached to the board, and the other functions as a stylus for note playing. You can see more on this creation in the video below, including a great performance starting at 3:45.