10 cm houfnice vz. 30 (howitzer) 10 cm houfnice vz. 30 (howitzer) The 10 cm houfnice vz. 30 (howitzer model 30) was a Czechoslovak howitzer used in the Second World War. The 158 weapons captured after the German invasion of Czechoslovakia in March 1939 were taken into Wehrmacht service as the 10 cm leFH 30(t). It was used by a variety of German units during World War II, including II. and III./SS-Artillerie-Abteilung 3 between 1939 and 1940 and SS-Artillerie-Abteilung 51 during 1941. 30 served with the Slovak Army. It was modified from an earlier Skoda design, the 10 cm houfnice vz. 28, that attempted to combine
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