66% or better

Flower with PCB pot and LED blossoms

[Johannes Agricola] recently held a workshop at the Peace Mission in Goettingen, Germany where he shared his RGB LED flowers. The small round PCB hosts an ATmega88 microcontroller which is running the V-USB stack so that the unit can be controlled by a computer. Each flower blossom is an RGB LED connected with four enameled wires which, when twisted together, make up the stem of the flower. [Johannes] took tons of pictures during the assembly while offering soldering advice along side the illustrations. The PCB is single-sided helping make this a great project for someone trying out surface mount component soldering for the first time. Or if you want something a little more free-formed try out this lemon-juice powered LED flower.

RF transmission in the 9 KHz band

[W1VLF] is on a quest to communicate over long distances with a 9 kilohertz transmitter. He built this giant coil with that in mind. A round concrete form was used as a base and wound with magnet wire by hand. We’d recommend building an automated winding device, but this method seems to have worked. Operating at 50 Watts on the air-core coil at 8.97 KHz he was able to pick up the signal at a distance of 5 kilometers. It’s not breaking any overall distance or portability records, but on a project like this the quest is where the fun is at.

[Thanks Drone]