Uploaded December 2011 | Updated September 2026, 1 day ago
My set of $.99 battery powered LED Christmas lights gets a brain upgrade. I programmed an ATtiny13 with a simple "blinky light" program, and then moved it to some perf board, which also contains a 7805 5V regulator and a couple of 2N3904 transistors to switch them on and off. (Astute viewers will note the lack of decoupling caps and filter caps on the 7805, I like living on the edge. I'll get them in, don't fret!) The whole thing is powered by a 9V battery, and will get put in my Santa hat!
My set of $.99 battery powered LED Christmas lights gets a brain upgrade. I programmed an ATtiny13 with a simple "blinky light" program, and then moved it to some perf board, which also contains a 7805 5V regulator and a couple of 2N3904 transistors to switch them on and off. (Astute viewers will note the lack of decoupling caps and filter caps on the 7805, I like living on the edge. I'll get them in, don't fret!) The whole thing is powered by a 9V battery, and will get put in my Santa hat!
