Page 16 - The Illustrated Dictionary of Electronics

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A1. Symbol for GAIN. 2. Symbol for AREA. 3. Sym- Abbe condenser 1. In microscopy, a special two-
bol for AMPERE (SI unit for current). piece lens that has enhanced light-gathering
A Symbol for negative terminal of filament-voltage power. 2. A similar focusing device in an electro-
source in a vacuum-tube circuit. magnetic antenna.
A Symbol for positive terminal of filament-voltage abbreviated dialing In telephone systems, special
source in a vacuum-tube circuit. circuits requiring fewer-than-normal dialing op-
a1. Abbreviation of ATTO- (prefix). 2. Abbreviation erations to connect subscribers.
of AREA. 3. Abbreviation of ACCELERATION. abc 1. Abbreviation of AUTOMATIC BASS COM-
4. Abbreviation of ANODE. 5. Obsolete abbrevia- PENSATION, a system for boosting the volume of
tion of cgs prefix AB-. bass sounds at low amplifier gain. 2. Abbrevi-
aA 1. Abbreviation of attoampere. 2. Obsolete for ation of AUTOMATIC BIAS CONTROL. 3. Abbrevi-
ABAMPERE. ation of AUTOMATIC BRIGHTNESS CONTROL.
AAAS Abbreviation for American Association for the 4. Abbreviation of AUTOMATIC BRIGHTNESS
Advancement of Science. COMPENSATION.
AAC Abbreviation of automatic aperture control abcoulomb The unit of electrical quantity in the
(NASA). cgs electromagnetic system. One abcoulomb
AAS Abbreviation of advanced antenna system equals 10 coulombs and is the quantity of elec-
(NASA). tricity that flows past any point in a circuit in one
AASR Abbreviation of airport and airways surveil- second when the current is one abampere.
lance radar. aberration 1. Distortion from perfect shape in a
AB Abbreviation of acquisition beacon (NASA). lens or reflecting mirror or antenna dish. 2. A
A-B In sound and acoustics, the direct comparison small error in the determination of the direction
of two sources of sound by alternately turning on of a source of electromagnetic energy, on account
one and the other. of the motion of the source and/or the detecting
ab- 1. Prefix that transforms the name of a practi- apparatus. 3. A small displacement in the appar-
cal electrical unit to that of the equivalent electro- ent positions of the stars from month to month on
magnetic cgs unit (e.g., ABAMPERE, ABOHM, account of the earth’s orbital motion.
ABVOLT). See individual entries of such cgs ABETS Acronym for airborne beacon electronic test
units. 2. Abbreviation for ABSOLUTE. set (NASA).
abac A graphic device for the solution of electronics abfarad The unit of capacitance in the cgs electro-
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problems. Also see ALIGNMENT CHART. magnetic system. One abfarad equals 10 farads
abampere The unit of current in the cgs electro- and is the capacitance across which a charge of
magnetic system. One abampere equals 10 1 abcoulomb produces a potential of 1 abvolt.
amperes and corresponds to 1 abcoulomb per abhenry The unit of inductance in the cgs electro-
second. magnetic system. One abhenry equals 10 –9 henry

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