Circuit board formed with spark gap

DETAILED DESCRIPTION What is claimed is: 1.
A circuit board formed with a spark gap comprising: a substrate made of an electrical insulator; a first electrode disposed on said insulator substrate and having a tip portion; a second electrode disposed opposite to said first electrode on said insulator substrate and having a tip portion spaced apart by a predetermined first distance from the tip portion of said first electrode; a first metal ball electrically connected to said first electrode and disposed on the tip portion of said first electrode at a precise position so as to be spaced apart by a second distance which is shorter than said first distance from the tip portion of said second electrode; first positioning means formed on the position of said insulator substrate on which said first metal ball is disposed for holding said first metal ball at the precise position; a second metal ball electrically connected to said second electrode and disposed on the tip portion of said second electrode at a precise position so as to be spaced apart by a third distance which is shorter than said first distance from the tip portion of said first electrode; and second positioning means formed on the position of said insulator substrate on which said second metal ball is disposed for holding said second metal ball at the precise position.
2.
A circuit board formed with a spark gap comprising: a substrate made of an electrical insulator in which there are provided first and second spaced recesses disposed adjacent to each other and spaced apart by a predetermined first distance; a first metal ball, the diameter of which is larger than that of a first spaced recess formed in said insulator substrate, and which is disposed on said first spaced recess; a second metal ball, the diameter of which is larger than that of a second spaced recess formed in said insulator substrate, and which is disposed on said second spaced recess; a first electrode, which is disposed in proximity to said first spaced recess on said insulator substrate and is spaced apart by a second distance which is longer than said first distance from said second spaced recess, and which is electrically connected to said first metal ball; and a second electrode, which is disposed in proximity to said second spaced recess on said insulator substrate and is spaced apart by a third distance which is longer than said first distance from said first spaced recess, and which is electrically connected to said second metal ball