The Jar of Fireflies is the second iteration of a firefly lamp I made with one string of lights. I wanted to make a jar of fireflies that felt more organic than the first one I made. I also wanted to make the switch as simple as a turn of the jar lid. I wanted to create a magical feeling of organic and glowing objects. This object could function as a nightlight or centerpiece for an indoor or outdoor table-setting. It is for anyone who likes mysterious and magical objects. Check out my instructable on how to make it!
The biggest challenge was finding out what kind of resisters to use with the cut up light strings. I read on some forums and discovered that 47 Ohm resistors were needed. I then soldered them to the positive leads of each light string before connecting that to the Gemma. then I had to attach copper tape to the lid rim on the inside. I also soldered the negative lead from the battery cable to copper tape and placed that in the lip of the jar. So when someone closes the lid the two copper pieces make contact and that completes the circuit to send power to the gemma and start the lights going.
The Firefly Jar is made with Arduino code programmed onto a Gemma. I also used LED string lights from Sparkfun, copper tape, glue, paper, solder, a rechargable 3.7 V battery and a Ball Jar. The light turns on with a twist of the lid. Code on Github.