Vintage Chart of the Electromagnetic Spectrum, and Nikola Tesla’s Historic Invention

This is a chart of the electromagnetic spectrum, published by the W.M. Welch Scientific Company in 1944, and posted online about three years ago.  It covers electromagnetic radiation from simple diffraction to cosmic rays, and shows the frequency allocations and their historic use across the spectrum.  (full resolution image is here) When Nikola Tesla established … More Vintage Chart of the Electromagnetic Spectrum, and Nikola Tesla’s Historic Invention