10 cm houfnice vz. 28 10 cm houfnice vz. 28 The 10 cm houfnice vz. 28 (howitzer model 28) was a Czech howitzer used in limited numbers by the Yugoslav Army during World War II. The Yugoslavians ordered twenty houfnice vz. 28 guns which they referred to as the 100 mm M.28. Guns captured from Yugoslavia by the Germans were given the designation 10 cm leFH 317(j). The origins of the houfnice vz. 28 began in 1928 at the Škoda Works in Pilsen. The design attempted to combine the howitzer and mountain gun roles into one weapon. The houfnice vz. 28 combined a two-wheeled box
Field emission gun Field emission gun A field emission gun is a type of electron gun in which a sharply pointed Müller-type emitter is held at several kilovolts negative potential relative to a nearby electrode, so that there is sufficient potential gradient at the emitter surface to cause field electron emission. Emitters are either of cold-cathode type, usually made of single crystal tungsten sharpened to a tip radius of about 100 nm, or of the Schottky type, in which thermionic emission is enhanced by barrier lowering in the presence of a high electric field. Schottky emitters are made by coating a tungsten tip