Fredrik Jansson enjoys tinkering with electronics and is a licensed radio amateur. He works as a researcher on the physics of clouds at the Delft University of Technology and develops weather models that run on supercomputers. He has a PhD in Physics from Abo Akademi University in Finland, and lives in Amsterdam. Charles Platt is a contributing editor and regular columnist for Make: magazine, where he writes about electronics and tools. Platt was a senior writer for Wired magazine, has written various computer books, and has been fascinated by electronics since he put together a telephone answering machine from a tape recorder and military-surplus relays at age 15. He lives in a Northern Arizona wilderness area, where he has his own workshop for prototype fabrication and the projects that he writes about for Make: magazine.