Experimental investigation of a tetrode gun for MM-wave TWTs

A tetrode-type electron gun suited for millimeter-wave TWTs has been investigated experimentally. The gun creates ultra-laminar 18 kV, 0.1 microperveance beams utilizing voltage swings between -100 V and +50 V on the inner grid and between -300 V and +200 V on the outer grid. This gun was fabricated by joining tight-tolerance parts into assemblies that each exhibited both non-concentricity and axial-position errors of about 0.001 inches.