A few days ago I came across a product that is being funded on Kickstarter (the most popular crowdfunding site); a device that charges your cell phone by harvesting energy from radio waves that exist in the environment. Cool right? Free energy !!!
It sounds at least feasible if you reduce the power consumption of electronic devices and if it gets perfected, who knows, it could mean the end of wall chargers or portable batteries!
I imagined a world with many devices charging with energy available in the environment, but while I was transported to the future in my time capsule I was assaulted by a Deja Vu ... "I've heard this before, long before."
I rummaged through the souvenir drawers a bit and found it. I've actually seen this concept at work before, but sooner even than I imagined.
I found out from a story my grandmother told me that my dad, as a teenager, had made a radio receiver out of a strange rock. It seemed like a fantastic story to me and for some years of my childhood I was intrigued by the story, trying to find more clues to that magical device.
Years later I learned that it was a galena or crystal radio. I mean, surely the rock my father had used was a galena rock. A mineral composed of lead and sulfur.
You could say that a crystal radio is the simplest radio receiver to build possible. However, the interesting thing is that it does not need to be powered by energy ... YES, YOU READ GOOD ... It works without batteries, without solar panels, without the need to connect to the electricity grid, nothing, nothing like that. The energy with which it works comes from the radio waves it consumes and the most interesting thing is that it was conceived in the 19th century.
At the beginning of the 20th century, its use became popular and was part of the entertainment of many families and enthusiasts, who thanks to this device could listen to transmissions from miles away, even on the other side of our planet.
In a future article I will explain HOW TO BUILD A CRYSTAL RADIO and of course, go back to the past listening to radio programs in "the old way".