Ammonium chloride to Anechoic.

Ammonium chloride to Amplifier, line
obtained chiefly by the dry distill­ation of nitrogenous ,bodies such as coal. The most important source of ammonia is the union of nitr~gen and hydrogen with in-creased pressure and temperature in presence of iron.
Ammonium chloride. (Chem.) Com­monly known as sal ammoniac. When dissolved in water it is used as an electrolyte for some primary cells.
Amorphous. Without definite form; unorganized. (Chern. Plast.) Devoid of crystalline structure.
Ampere. (Elec.) The unit of measure­ment of electric current strength. A pressure of one volt will force one ampere through a resistance of one ohm.
Ampere Andre Marie. French physi­cist and scientific writer - 1775 to ­1836, whose name. is given to the unit of measurement of electric current strength (the ampere).
Ampere hour. (Elec.) Used in rating storage batteries, representing a current of one ampere flowing for one hour.
Ampere meter. (Elec.) Same as am­meter. A meter to register the den­sity of flow of current.
Ampere turns. (Elec.) The product obtained by multiplying the number or turns in a magnetic coil by the current strength in amperes.
Amphibian. (Aero.) An airplane built to arise from and alight on either water or land.
Amphibole. Short fiber asbestos. Amplifier. (Elec.) A device for in­creasing the strength of weak currents or sounds.
Amplifier, Balanced. An amplifier with high (+) and low (-) signal connections and a separate shield (ground) connection. This 3-wire approach can be achieved with a transformer or with special elec­tronics. An amplifier can have a balanced input and output, or it may have the input unba~anced and the output balanced, or vice­versa. The term "balanced" does not refer to frequency or level balance. (also see "balanced".)
Amplifier, buffer. "Buffer amplifier" is another term commonly used to refer to an isolation amplifier.
Amplifier, isolation. An amplifier which is used to minimise the ill­teraction between the circuitry which precedes and that which follows. Also known as a "buffer amplifier".
Amplifier, line. An amplifier which supplies an audio system or a log cable with a signal at a specified level, usualIy between -10 and +4DBV (245 millivolts to 1.23

volts RMS).
Amplifier, monitoring. A power am­plifier used primarily to drive loud­speakers for audible evaluation of a programme.
Amplitude. (Math.) An angle upon which the value of some mathe­matical function depends. (Phys.) The distance covered by a particle in IT!akling a complete vibration.
Amplitude cartridge. Cartridge with output voltage proportional to amplitude of stylus displacement. Employs piezo-electric or strain­gauge transducer and compensates approximately for recording char­acteristic when used with appro­priate load impedance.
Amplitude distortion. Alteration of sensitivity or amplification factor with change of signal level, both overall and within each cycle of signal wave-form. Arises from nOIl­lillearity of trallsfer characteristic and produces harmonic and 1M distortion.
Amplitude Modulation. The super­imposing of an or audio signal on a pure sine wave such that the modulating signal challges the amplitude (level) of the pure sine wave, or vice-versa.
Analogous colours. Closely related colours. e.g., redorange, and yellow-orange, etc.
Analyser. The second Nicol prism in a polarimeter: when rotrated .
90E relative to polariser it will not allow polarised light to pass.
Analysis. (Chem.) The resolution of a compound into its parts or ele­ments. (Math.) A tabulated state­ment; the process of resolving a problem into its first elements.
Analytical geometry. (Math.) The study of geometric figures by the process of algebraic analysis.
Anchor. (Arch.) The pointed orna­ment forming an element of the eggand-dart molding. (Bldg.) That bolt or fastening device which at­taches to the anchorage. (Fdry.) A metal support for holding a core in place.
Anchorage. That permanent place­ment to which the lower members of a structure may be attached in order to secure greater stability for the entire structure.
Anechoic. Without echo. An anechoic evironment is one where little or no sound is reflected. An
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