I usually take a note or sketch when I create a new circuit. I thought I did when I installed “threshold” on the site at Onondaga Community College (OCC) in May 2007. The brownish circuit board in the photo is the original one, which was installed through a program called, Art Across Campus at OCC. It was mailed to my place because a MP3 player with this circuit stopped playing.
I was surprised when I opened the box because it is very clean even it was installed in a PVC box which was kept outside of building for two years. Then, it is still in working condition. The MP3 player made by a okay company is dead, but not my circuit, which makes me feel better. I should make MP3 player myself? Well.., it would be too complicated with little budget.
Since I can’t find the sketch for this circuit, I copied it on the breadboard. I think I should improve the sound quality for future use. “threshold” will be lent until May 2011.