DETECTOR.--Any device that will (1) change the oscillations set up by the incoming waves into direct current, that is which will rectify them, or (2) that will act as a relay.
- Carborundum.--One that uses a carborundum crystal for the sensitive element. Carborundum is a crystalline silicon carbide formed in the electric furnace.
- Cat Whisker Contact.--See Cat Whisker Contact.
- Chalcopyrite.--Copper pyrites. A brass colored mineral used as a crystal for detectors. See Zincite.
- Contact.--A crystal detector. Any kind of a detector in which two dissimilar but suitable solids make contact.
- Ferron.--A detector in which iron pyrites are used as the sensitive element.
- Galena.--A detector that uses a galena crystal for the rectifying element.
- Iron Pyrites.--A detector that uses a crystal of iron pyrites for its sensitive element.
- Molybdenite.--A detector that uses a crystal of sulphide of molybdenum for the sensitive element.
- Perikon.--A detector in which a bornite crystal makes contact with a zincite crystal.
- Silicon.--A detector that uses a crystal of silicon for its sensitive element.
- Vacuum Tube.--A vacuum tube (which see) used as a detector.
- Zincite.--A detector in which a crystal of zincite is used as the sensitive element.
DE TUNING.--A method of signaling by sustained oscillations in which the key when pressed down cuts out either some of the inductance or some of the capacity and hence greatly changes the wave length.
DIELECTRIC.--An insulating material between two electrically charged plates in which there is set up an electric strain, or displacement.
DIELECTRIC STRAIN.--The electric displacement in a dielectric.
DIRECTIONAL AERIAL.--See Aerial, Directional.
DIRECTION FINDER.--See Aerial, Loop.
DISCHARGE.--(1) A faintly luminous discharge that takes place from the positive pointed terminal of an induction coil, or other high potential apparatus; is termed a brush discharge. (2) A continuous discharge between the terminals of a high potential apparatus is termed a convective discharge. (3) The sudden breaking-down of the air between the balls forming the spark gap is termed a disruptive discharge; also called an electric spark, or just spark for short. (4) When a tube has a poor vacuum, or too large a battery voltage, it glows with a blue light and this is called a blue glow discharge.
DISRUPTIVE DISCHARGE.--See Discharge.
DISTRESS CALL. [Morse code:] ...---... (SOS).