He said that he had done this with the help of a 50-foot tesla coil. "Jack Shows Meg His Tesla Coil". Tesla coil is likely to be fatal. This tube has also been used by hobbyists to construct a vacuum tube Tesla coil. Munich's project focused on improving the original Tesla coil, producing a working model. As a consequence, the output of a Tesla coil can be dangerous or even fatal. He then used a Tesla coil to power his staff. In the same year, he patented his Tesla coil. The Tesla coil primary winding, spark gap and tank capacitor are connected in series. The Tesla coil was used as a musical instrument on the song "Thunderbolt". Until the 1920s noisy spark-discharge Tesla coil and Oudin coil machines were used. The term "Tesla coil" is applied to a number of high voltage resonant transformer circuits.