In the days before semiconductor diodes, transistors, or even vacuum tubes, mechanical means were used for doing many of the same things. But there’s still plenty of fun to be had in using those mechanical means today, as [Manuel] did recently with his relay computer. This post is a walk through some circuits that used those mechanical solutions before the invention of the more electronic and less mechanical means came along.
It is said that “success has many fathers, but failure is an orphan.” Given the world-changing success of radio in the late 19th and early 20th centuries, it’s no wonder that so many scientists, physicists, and engineers have been credited with its invention. The fact that electromagnetic radiation is a natural phenomenon that no one can reasonably claim to have invented sometimes seems lost in the shuffle to claim the prize.
But it was exactly through the study of natural phenomena that one of the earliest pioneers in radio research came to have a reasonable claim to at least be the inventor of the radio receiver, well before anyone had learned how to reliably produce electromagnetic waves. This is the story of how a Russian physicist harnessed the power of lightning and became one of the many fathers of radio.
Here’s an interesting project to plot every lightning strike on Earth. Blitzortung is a project that uses many extremely low-cost sensor boards packed with an amplifier, microcontroller, and an Ethernet socket to detect lightning strikes. When multiple stations send all that data up to a server, the location of lightning strikes can be calculated, even if they’re hundreds of miles away from any station.
Each station works by detecting a change in the local EM field caused by a lightning strike with either a large loop antenna or a smaller ferrite core antenna. These signals can be amplified and turned into usable data, time stamped, and sent out on the Internet. From there, it’s a simple time of flight calculation to precisely locate where lightning strikes.
The hardware is actually pretty simple, with based on an STM32F4 Discovery board. A controller includes an Ethernet port, GPS unit, LCD, and all the hardware associated with detecting lightning strikes.
If you’d like to see what’s possible with a huge network of lightning detectors connected to the Internet you can check out LightningMaps for a look at what’s possible.
Thanks [Sean] for sending this in.