Spark gap machine.
<video controls autoplay loop> <source src="https://s3-us-west-1.amazonaws.com/hmt-forum/rotary_spark_gap_machine.mp4" type="video/mp4"> Your browser does not support the video tag. </video>
Previously:
https://www.homemadetools.net/forum/...576#post201233
https://www.homemadetools.net/forum/...864#post190796
https://www.homemadetools.net/forum/...250#post150146
