From a purely economic standpoint, the ATtiny85 makes sense.
QuoteFrom a purely economic standpoint, the ATtiny85 makes sense.eh? Assuming simple blinking it the desired functionality, a 555 is $0.41, an ATtiny85 is $1.18 (qty 1, digikey).The 555 needs a few passives (less than $0.77 worth, I'd wager) and requires more assembly work (which could be viewed as an advantage, for a kit).-j
Ah, so not "simple blinking". -j
Jack is a pleasure to deal with.
I sanded off a small patch of solder mask, tinned the copper with a very large iron, then soldered on a clip from a pin. You can now wear this unit on your shirt. It looks great. I also substituted the dim red led's with surface mount blue LED's. Don't have a picture of that at the moment, though.
I'm wondering if you could put an insulated safety pin on the front too so it only works when the safety pin is hooked up?