Making a spherical audion vacuum tube part1

The start of the radio revolution came with Lee de Forest inventing the triode vacuum tube. One of his first tubes and the most famous is the spherical audion triode vacuum tube. The tubes were made using the spherical envelopes of auto headlamp bulbs, which were commonly available back in 1905. Even though thousands were made back then, the vast majority ended up in the landfills so they are very rare now. This video shows how a reproduction of the spherical audion is made.