McGRAW-HILL
`
`ELECTRONICS
`
`DICTIONARY
`
`SIXTH EDITION
`
`NEIL SCLATER
`
`JOHN MARKUS
`
`McGraw-Hill
`NewYork San Francisco Washington. DC. Auddand Bogota
`Caracas Lisbon London Madrid Mexico City Milan
`Montreal New Delhi San Juan Singapore
`Sydney Tokyo Toronto
`
`VW EX1010
`
`US. Patent No. 6,557,540
`
`VW EX1010
`U.S. Patent No. 6,557,540
`
`

`

`Library of Congress Cataloging-in-Pnblication Data
`
`n the earlier edition.
`
`I. MarkusJohn,19ll—
`
`Sclater, Neil.
`_
`McGraw-Hill electronics dictionary I Not] Sclater, John Markus. ——
`6th ed.
`cm.
`p.
`Markus' name appears first 0
`Includes index.
`ISBN 0-07-057837-0
`1. Electrodes—Dictionaries
`[1. Title.
`TK7804.M354
`621.38’03—dc21
`
`1997
`
`97-16168CIP
`
`I © 1997. 1994, 1978, 1945 by McGraw-Hill, Inc. All rights reserved.
`Capyfigh
`America. Except as permitted under the
`Printed in the United States of
`976, no part of this publication may be
`United States Copyright Act of 1
`reproduced or distributed in any form or by any means, or stored in a data
`base or retrieval system, without the prior written permission of the pub-
`lisher. Copyright © 1966, 1960 under the title Electronics and Nucleonics
`Dictionary. All rights reserved.
`‘
`
`234567890 DOCJDOC 90210987
`
`ISBN 0-07-057837-0
`
`The sponsoring editorfor this book was Steve Chapman, the editing
`supervisor was M. R. Carey, and the production supervisor was Clare
`Stanley. It was set in Times Roman by North Market Street Graphics.
`
`Printed and bound by R. R. Donnefley & Sons Company.
`
`Information contained in this work has been obtained by McGraw-Hill, Inc. from
`sources believed to be reliable. However, neither McGraw-Hill nor its authors
`
`sousht.
`
`guarantee the accuracy or completeness of any information published herein and
`neither McGraw—Hill nor its authors shall be responsible for any errors, omissions,
`or damages arising out of use of this information. This work is published with the
`understanding that McGraw-Hill and its authors are supplying information but
`are not attempting to render engineering or other professional services. If such
`semces are required, the assistance of an appropriate professional should be
`
`

`

`——-_.__
`
`---u-u un- -
`
`--v—
`
`equivalent series resistance
`
`sitic effects in circuits being rapidly switched. See parasitic
`efiects.
`equivalent series resistance [ESR] The effective resis-
`tance in series with an “ideal" capacitor caused by internal
`leads or the positions of internal elements.
`elluivalent
`sound absorption The
`area of perfectly
`absorbing surface that will absorb sound energy at the
`same rate as the given surface or object under the same
`conditions The acoustical unit of equivalent absorption is
`the sabin.
`equivalent stopping power
`2. Stopping equivalent.
`erasable programmable read-only memory [EPROM] A
`nonvolatile semiconductor ROM memory that can be
`erased by exposure to ultraviolet (UV) fight and rewritten
`electrically. The chip is covered with a quartz window per— _
`mitting it to be exposed to UV light for erasure. The wrn-
`dow is
`recovered with opaque material before the
`EPROM is reprogrammed. See also EEPROM and 0T0
`EPROM.
`
`1. Relative stopping power.
`
`erasable storage A storage whose data can be altered at
`any time.
`erase
`1. To remove recorded material from magnetic
`tape by passing the tape through a strong, constant mag-
`netic field (DC erase) or through a high-frequency alter-
`nating magnetic field (AC erase).
`2. To change all the
`binary digits in a digital computer memory to binary zeros.
`3. To eliminate previously stored information in a charge-
`storage tube by charging or discharging all storage ele-
`ments
`
`erase oscillator The oscillator in a magnetic recorder that
`provides the high-frequency signal needed to erase a
`recording on magnetic tape. The bias oscillator usually
`serves also as the erase oscillator.
`erasing head A magnetic head that obliterates material
`previously recorded on magnetic tape.
`ERC Abbreviation for electrical rules check.
`E region The region of the ionosphere extending from
`about 60 to 90 mi (95 to 160 km) above the earth, between
`the D and F regions -
`erg The absolute CGS unit of energy and work. It is the
`work done when a force of 1 dyn is applied through a dis-
`tance of 1 cm. One foot-pound is equal to 13.56 x 106 ergs.
`ergonreter An instrument for measuring the amount of
`work performed by specific muscles in the body under
`controlled conditions
`
`ergonomics The science and technology related to the
`design and manufacture of tools, controls, equipment, and
`furniture best suited for long—term human use in homes,
`offices, factories, ships, aircraft, and vehicles. The term
`means “measurement of work.” It considers all aspects of
`the environment such as lighting, temperature, humidity,
`and ambient noise as well as human physiological limita-
`tions and fatigue. Its objectives are to maximize human
`work performance safely. A well-designed workstation
`will include provisions for long-term comfort, protection
`against excessive noise or other potential dangers, and
`provtsrons for variations in operator size and weight.Tools
`and controls are designed to fit the hands andfor feet com-
`fortably and will be made of appropriate materials in sizes,
`shapes, and colors that promote safety and efficient use. It
`is also called human factors engineering.
`
`Erlang A unit of communication traffic d
`-
`the average number of simultaneous calls 2:122” c9113] to
`ing a specific hourly period.
`med dur—
`ERP Abbreviation for efiective radiated power
`error
`1. The difference between the true value a d
`culated or observed value.
`2. Mfllfimcticpm
`n a Ca]-
`error amplifier An operational or differential ampljfi
`er
`that controls feedback 111 a closed-loop circuit or s st
`produces an error voltage when the sensed can}; 512- It
`from the reference voltage. In switching power Sn
`1: en;
`adjusts the pulse-width modulator to correct infirm
`output voltage. See reference amplifier.
`“m
`error code A specific character entered into a disk ta
`or memory to indicate that a conscious error was madepi:
`the associated block of data. Machines reading the error
`code can be programmed to throw out the entire block
`automatically.
`error-correcting code A code in which each data signal
`conforms to rules so that errors in received signals can be
`automatically detected and some or all of the errors my.
`rected automatically.
`Self—checking code.
`errondetecting code
`error detection and correction [EDC] A process for stor-
`ing digital data that has first been given a digital tag
`derived from that data. When the data is retrieved, the tag
`is used to check the data for correction.
`error rate The ratio of the number of erroneous charac-
`ters to the total number of characters received in a data.
`transmission system.
`error-rate damping A type of damping in which servo
`control is accomplished by two voltages: one proportional
`to the error, and the other proportional to the rate at
`which the error changes. It is also called a proportional
`plus derivative control.
`error signal A voltage or current proportional to the dif-
`ference between the desired and the actual response in a
`closed-loop system.
`error voltage A voltage, usually obtained from a tachome—
`ter whose output is proportional to the difference between
`the angular positions of the input and output shafts of 3
`servosystem. This voltage acts on the system to produfl? a
`motion that tends to reduce the error in position. It 15 3150
`called an error signal.
`.
`ERTS Abbreviation for earth resources technology 55’9”“
`Esaki diode Tunnel diode.
`escape velocity The minimum velocity that will enable 311
`object to escape from the surface of a planet or pther bong
`without further propulsion. The escape veloctrl for tiih
`earth is 25,020 mifh (40,266 kmlh); for the moon, 5364 m
`(8633 km/h).
`h mi-
`ESCA Abbreviation for electron spectroscopy for c e
`calT analyst's.
`_
`E scope A radarscope that produces an E displal- 'ndOWv
`escutcheon An ornamental plate around a £1131- “'1
`control knob, or other panel-mounted part.
`face
`.
`ESD Abbreviation for electrostatic discharge.
`ESDI Abbreviation for enhanced small-deities mm
`ESP Abbreviation for earth-surface potential-
`.
`a
`ESU Abbreviation for electroflatic unit.
`d in the
`etalon An optical device consisting of W0 5P
`16L and partially silvered glass plates When Place I
`l'O'
`cavity of a laser, the etalon is tilted at an angle that P
`
`152
`
`

`

`TILTED E'MLON
`
`”
`
`LASER GAIN MEDIUM
`
`H
`
`Etalon in single—frequency laser.
`
`vides enough reflection to prevent oscillation at all
`unwanted axial modes of the long cavity.
`ad,
`1_ The removal of copper lamination bonded to a
`circuit board substrate by acid etch with a subtractive
`mask and etch process that forms the conductors, lands.
`and Pads on a printed circuit board.
`2. The removal of
`semiconductor material, oxide, or thin metal films by acid
`or plasma (ion) bombardment such as nitride and oxide
`etch.
`
`etchant An acid that removes unwanted materials such as
`metal or oxides from a substrate.
`etched printed circuit A printed circuit formed by chemi-
`cal etching or chemical and electrolytic removal of
`unwanted portions of a layer of conductive, typically cop-
`per foil material, bonded to an insulating base.
`etching The act of removing unwanted portions of a metal
`or semiconductor by chemical or electrolytic action.
`ETDMA Abbreviation for enhanced time-division multi-
`access
`
`Ethernet A local area network (LAN) software standard
`that determines system operation. It is organized with
`software, circuit cards, and adapters in each computer or
`terminal in the network.
`
`ETPC Abbreviation for electrolytic tough pitch copper
`ETSI Abbreviation for European Telecommunications
`Standards Institute
`
`Ettiagshausen efiect When a metal strip is placed with its
`plane perpendicular to a magnetic field and an electric
`current is sent longitudinally through the strip, corre-
`sponding points on opposite edges of the strip will have
`different temperatures.
`ETV Abbreviation for educational television.
`E unit A method of designating radar signal-to-noise
`ratio. E-l is a 1 to 1 ratio, barely perceptible; E-2 is 2 to 1.
`W631i: E-3 is 4 to 1, good; B4 is 8 to 1, strong; BS is 16 to 1,
`Very strong or saturating.
`EUT Abbreviation for equipment under test.
`eutectic The liquid alloy composition with the lowest
`3362ng point. For lead-tin solder, the eutectic is 63% tin
`and 37% solder, giving a freezing point of 361°F.
`EV Abbreviation for electronvolt.
`evacuate To remove gases and vapors from an enclosure.
`Also called exhaust.
`evacuation The removal of gases and vapors from the
`envelope of an electron tube during manufacture.
`emesoeut mode The mode of oscillation in which the
`ampIitude diminishes along a waveguide without change
`of phase.
`“3130"!“ The material that is to be deposited as a thin
`film by evaporation.
`"alienated dielectric film A film of dielectric material
`deposited by vacuum evaporation for passivation of com-
`POnents with active and passive films. It is also used as a
`calliacitor dielectric in thin-film capacitors
`
`EXCLUSIVE-0R gate
`
`emporation The process of vaporizing a material by heat
`in a vacuum to produce a thin film.
`evaporative-cooled Vaporization-cooled.
`BIC Abbreviation for enhanced video connection stan-
`ard.
`E vector A vector that represents the electric field of an
`electromagnetic wave. In free space it is perpendicular to
`the H vector and the direction of propagation.
`even harmonic A harmonic that is an even multiple of the
`fundamental frequency.
`even parity check A method of detecting when bits are
`dropped by adding 1 bit whenever a character is repre-
`sented by an odd number of bit patterns. All characters are
`then represented by an even number of bits, and failure to
`do so is thus a parity error.
`EVR Abbreviation for electronic video recording.
`EW Abbreviation for electronic warfare
`F. wave British term for transverse magnetic wave (TM
`wave).
`exa- [abbreviated E] A prefix representing 10‘“.
`EXCEPT A logic operator that has the property that if P
`and Q are two statements, then the statement P EXCEPT
`Q is true only when P alone is true. It is false for the other
`three combinations (P false Q false, P false 0 true, and P
`true 0 true).The EXCEPT operator is equivalent to AND
`NOT.
`
`EXCEPT gate A gate that produces an output pulse only
`for a pulse on one or more input lines and the absence of a
`pulse on one or more other lines
`excess electron An electron in excess of the number
`needed to complete the bond structure in a semiconduc-
`tor, generally resulting from donor impurities
`excess-three code A number code in which the decimal
`digit n is represented by the 4-bit binary equivalent of n +
`3, so decimal digits 0 through 9 become 0011, 0100, 0101,
`0110, 0111, 1000, 1001,1010,1011, and 1100, respectively.
`excitation
`1. The signal voltage that is applied to the con-
`trol electrode of an electron tube.
`2. Application of sig-
`nal power to a transmitting antenna.
`3. The transfer of a
`nuclear system from its ground state to an excited state by
`adding energy.
`4. The application of voltage to field
`coils to produce a magnetic field, as required for the Oper-
`ation of an excited-field loudspeaker or a generator.
`excitation winding The magnetic amplifier winding that
`applies a unidirectional magnetomotive force to the core.
`excited-field loudspeaker Electrodynamic loudspeaker:
`exciter
`1. The part of a directional transmitting antenna
`system that is directly connected to the transmitter.
`2. A
`crystal oscillator or self-excited oscillator that generates
`the carrier frequency of a transmitter.
`3. A small auxil-
`iary generator that provides field current for an AC gener-
`ator.
`4. A loop or probe that extends into a resonant
`cavity or waveguide.
`S. Exciter lamp.
`exciting current Magnetizing current.
`exciton The combination of an electron and a hole in a
`semiconductor that is in an excited state. In attracting the
`electron, the hole acts as a positive charge.
`exclusion principle Pauli exclusion principle.
`EXCLUSIVE-0R gate A logic gate whose output is 1 if
`any one but not more than one of its inputs is 1. The out-
`put is 0 if more than one input is 1 or all inputs are 0. Also
`called XOR gate.
`
`163
`
`

`

`execute
`
`
`
`-
`
`exponential antenna A television Iece‘
`has a series of active elements “manteld
`3 amelma
`tha‘
`e]
`Fatal]
`other, with element lengths adiusted 5
`e
`to each
`two natural logarithmic curves. The a
`0 the”
`Dianna Pro 1:113 form
`gain over the VHF and UHF television b
`v des hi
`exponential decay Decay of radiationands.
`Eh
`strength. or some other quantity a; an exp‘ocha ‘
`signed
`rgc,
`exponential horn A horn Whose Cr0s3_s11e3ntlal rate,
`increases exponentially with axial diStance Ctional area
`
`XOR
`
`EXCLUSIVE OR gate: (a) logic symbol, (.5) schematic symbol, and
`(c) truth table.
`
`execute To perform the operations in the stored program
`of a computer.
`executive routine A digital computer routine designed to
`process and control other routines.
`exhaust Evacuate.
`
`exhaust tube A glass or metal tube through which air
`from the envelope of an electron tube is evacuated.
`exosphere A region of the atmosphere above the thermo—
`sphere, beginning at roughly 600 km, where the density is
`so low that an upward-traveling molecule makes no further
`collisions until it falls back to the base of the exosphere. At
`roughly 10,000 km the exosphere merges into the inter-
`planetary medium. 'Ihe exosphere overlaps the magneto-
`sphere.
`exothermic A condition of radiating heat or other energy.
`All radioactive processes are exothermic. It is also called
`exoergt'c.
`expanded sweep A cathode-ray sweep in which the move-
`ment of the electron beam across the screen is speeded up
`during a selected portion of the sweep time.
`expander The part of a compandor that is used at the
`receiving end of a circuit to return the compressed signal
`to its original form. It attenuates weak signals and ampli-
`fies strong signals.
`expert systems Computer programs written on a basis of a
`database gathered from the practical experience of experts
`in Specific fields or disciplines Examples include medical
`diagnostic programs, weather prediction (hurricane and tor-
`nado) programs, and earthquake or volcano eruption pro-
`gramsAll are based on personal experience, empirical data,
`readings from test instruments, history, and other factors
`exploring coil A small coil used to measure a magnetic
`field or to detect changes produced in a magnetic field by
`a hidden object. The coil is connected to an indicating
`instrument either directly or through an amplifier. It is
`also called a magnetic test coil or a search coil.
`exponential absorption The removal of particles or pho-
`tons from a beam at an exponential rate as the beam
`passes through matter.
`exponential amplifier An amplifier capable of supplying
`an output signal proportional to the exponential of the
`input signal.
`
`164
`
`
`
`Exponential horns, straight and curled.
`
`exponential transmission line A two-conductor transmig.
`sion line whose characteristic impedance varies exponen-
`tially with electrical length along the line.
`exposure dose A measure of X-ray or gamma radiation at
`a point, based on its ability to produce ionization. The unit
`of exposure dose is the roentgen.
`exposure-dose rate The exposure dose per unit time.
`The unit of exposure-dose rate is the roentgen per unit
`time.
`
`exposure meter An instrument that measures the inten-
`sity of light reflected from an object for the purpose of
`determining proper camera exposure. Modern exposure
`meters consist of a photovoltaic cell connected to an indi-
`cating meter.
`interchange. code
`decimal
`extended
`binary-coded
`[EBCDIC] A computer code in which 8 binary bits teP'
`resent a single character, giving a possible maximum of
`256 characters. It is the BCD code extended to 8 binall’
`bits EBCDIC-encoded messages are returned to the send'
`ing station for verification of data integrity.
`‘
`extended data output [EDO] A reference to a dymm”
`random access memory [DRAM] format that offers fastet
`speed, (approximately 60 ns) than the 70 to 80 as of 0011
`ventional DRAMS.
`An
`Extended Industry Standard Architecture [1515A]
`r0,
`extension for Intel 80386 microprocessors (and later Em,
`cessors) of the ISA bus for PC-compatible computers See
`provides compatibility with earlier ISA 535“”
`Industry Standard Architecture.
`of radio
`extra alactic radio source A discrete sourcpetore than
`signafit outside known galaxies 01‘ qua”? with radio
`10,000 such sources have been detecte
`to 100
`t'91'35‘3013‘35. at frequencies ranging from 10 MHz
`GHz.
`345 kV for
`extra-high voltage [EHV] A voltage above
`electric power transmission.
`flight that is
`extraordinary component The component 01
`rism- The
`plane-polarized and passes through 3 N15; Iii-ism-
`ordinary component is totally reflected by
`
`j
`
`

`

`terrestrial “Oi“ Cosmic, 501‘“! radio, and other elec-
`“may“? “is" frc’m sources nut related to the earth.
`extremely Ingll frequency [El-1F] A Federal Communica-
`tions Commlssmu desrgnatton for a frequency in the band
`from 30 to 300 6H2, COlTeSponding to a millimetric wave
`between 1 and 10 mm,
`emernely lowrrequency [ELF] A frequency below 300
`Hz or the radlo spectrum. corresponding to a Wavelength
`above 1000 km.
`extrinsic proppmeo _The properties of a semiconductor as
`modified bxlmpsmncs or Imperfections within the crystal.
`pr0358';gilfggegggmgzefiggigtgg£3105:filleclricol
`'
`6 Earn -
`conduCtOl' crys_tal,1n Contrast to an intrinsic semiconductolr
`
`whose properttes are characteristic of an idea] pure crysta]
`
`extrinsic semiconductor
`
`SURFACE
`
`
`EM NOISE FIELD
`
`-
`
`THAILING ANTENNA
`
`
`
`
`Ergremely low frequency signals, in range of 30 to 100 Hz. reach a
`so or
`.
`.
`.
`erged nuclear submarine tralhnglong antenna.
`
`165
`
`

`

`
`
`f Abbreviation for fcmto-.
`f Symbol for frequency.
`F 1. Symbol for first:
`2. Abbreviation for Fahrenheit.
`Abbreviation for fared.
`c’F Abbreviation for degree Fahrenheit.
`F— A-.
`F+ A+.
`
`3.
`
`[A Abbreviation for femroampere
`FAA Abbreviation for FederalAviatton Administration.
`FACCH Abbreviation for fast associated control channel.
`fab A slang (colloquial) term for the first part or “front
`end" of semiconductor manufacturing. See front-endfabri-
`canon.
`
`face bond A bond that is made directly between the
`bonding pad of a face-down semiconductor chip and a
`mating contact on a mounting substrate.
`faceplate The transparent or semitransparent glass front
`of a cathode-ray tube, through which the image is viewed
`or projected. The inner surface of the face is coated with
`fluorescent chemicals that emit light when hit by an elec-
`tron beam. Also called face.
`facsimile [fax] A system for transmitting and receiving
`text andtor graphics over the public telephone system. An
`electric signal representing the image of the subject copy is
`generated by optical scanning in a scanner and then is
`encoded before being transmitted by modem over the
`telephone lines to a compatible fax receiver or recorder,
`typically a machine capable of both transmitting and
`receiving. The speed of fax modems is typically 14.4 kbls.
`The receiving fax machine decodes the signal and converts
`it into a format for Operating a printer to print out a fac-
`simile copy based on the received signal.
`facsimile copy The printout of a fax machine on thermal
`or plain paper. See also subject copy.
`facsimile machine A modern personal or business machine
`that combines the dual functions of tax scanning and trans-
`
`mission and receiving and printout in a single integrated
`unit. In a common scanning method, the subject copy is
`inserted in the machine so it passes around a drum rotating
`at constant angular velocity. An optical carriage with a pho-
`tocell is mounted on a traverse drive belt that advances a
`distance equal to the height of a specified rectilinear area or
`horizontal strip across the width of the subject copy. The
`photocell generates a stream of pixels encountered in a
`helical-scan track. The output of the photocell or cells is con-
`verted by a modem for transmission over the public dial-up
`telephone line to a compatible fax machine that contains a
`mode for converting the data back to a signal that can be
`printed out on plain or thermal paper. Fax machines are
`typically assigned an exclusive telephone number so they
`can operate 24 hours a day without interfering with voice
`telephone service. Some machines can also serve as scan-
`ners or document digitizers for converting text and graphifi
`to a digital format for processing or storage by computer,
`and some can also serve as office copying machines.
`_
`facsimile signal The picture signal produced by scannlng
`the subject copy in a facsimile transmitter.
`facsimile transmission The transmission of digital data
`produced by scanning fixed graphic material, including
`photographs, for reproduction in record form.
`_
`_
`fade To change signal strength gradually
`fadeout A gradual and temporary loss of a received radio
`or television signal caused by magnetic storms, anno-
`spheric disturbances, or other conditions along the tran;
`mission path. A blackout is a fadeout that can last sever
`hours or more at a particular frequency.
`1
`fader A multiple-unit volume control for the grad?!-
`changeover from one microphone, audio channel, or tell?s
`vision camera to another. In each changeover, the leved 1r
`held essentially constant because one section of the fad;
`increases signal level in its channel while the other fa
`section reduces signal level a corresponding amount-
`
`166
`
`

`

`“V
`
`95
`
`11’
`IE
`
`(bu-D7
`
`the field st
`'
`'
`'
`rength of a radio ,
`fading Variations in
`all gradual, that are caused b ch
`.
`SignaL
`flag); medium.
`y
`anges “1 the trans-
`fading margin. An attenuation allowance in
`ade in radio
`systeln p1anning so that anticipated fading
`-
`-
`Wi
`-
`the signal above a spec1fied minimum signliilsittlci:riiiiiesi;1
`ratio-
`eslock dip A Spring-t
`termin
`'
`Egan eleilifiica‘i‘connectioye
`al formakinga ‘em'
`nheil
`temperature scale in whic
`.
`F333: of water is 32° and the boiling pom}: t3: 3:3???
`212° at normal EMOSPheriC pressure. Absolute zero is
`459.91; To change degrees Fahrenheit to degrees Celsi is
`subtract 32 and then multiply the result by 36. Fahrenhgfi
`and Celsius scales agree at one point: 4001: = 4006
`Multiply degrees Celsius by is and add 32 to get degrees-
`Fahrenheit.
`“1“.me control A control so designed that control-circuit
`failure cannot cause a dangerous condition under any cir-
`cumstanoes.
`[airlead A plastic, wood, or metal tube with a funnel-
`shaped end through which a trailing antenna is reeled on
`an aircraft.
`fall firm: The time for the voltage at the trailing edge of a
`pulse to fall from 90 to 10% of the original negative or
`positive amplitude. It is the opposite of rise time.
`false echo A misleading extra echo indication on the plan-
`position indicator of a ship’s radar set. On rivers, shore
`structures can cause false echoes A target can also be hit
`by a side lobe of the beam, and the echo reflected back
`into the main beam path by a mast, stack, or tower.
`[an beam 1. A radio beam having an elliptically shaped
`cross section in which the ratio of the major to minor axes
`usually exceeds 3 to 1. The beam is broad in the vertical
`plane and narrow in the horizontal plane.
`2. A radar
`beam with a fan shape.
`[an dipole See dipole antenna.
`Ian-in The number of inputs that can be connected to a
`digital logic gate.
`fan-iii circuit A circuit having many inputs feeding to a
`common point.
`
`FAN-IMB
`
`Fan-in circuit for logic gates
`
`11
`-
`.
`_
`‘
`fan marker Fan marker beacon.
`[In marker beacon A VHF radio facility With a Yemciixy
`directed fan beam intersecting an mayto pfond: 12nd:
`When used near an airport as part Of an Instrumen
`
`Faraday rotation isolator
`
`feeds many branches
`
`FAN-OUT=5
`
`Fan-out circuit with a fan-in circuit for logic gates.
`
`farad [F] The SI unit of capacitance. A capacitor has a
`capacitance of 1 F when a voltage change of] WS across it
`produces a current of 1 A. The farad is too large a unit for
`practical work, so two smaller units are generally used. The
`microfarad is equal to one-millionth of a farad, and the
`picofarad is equal to one-millionth of a microfarad.
`faraday A unit of quantity of electricity equal to 96,500 C.
`Faraday cage See Faraday shield.
`Faraday dark space The relatively nonluminous region
`that separates the negative glow from the positive column
`in a cold-cathode glow-discharge tube.
`Faraday effect When a plane-polarized beam of light
`passes through certain transparent substances in a direc-
`tion parallel to the lines of a strong magnetic field, the
`plane of polarization is rotated at certain amount. The same
`effect governs the action of a ferrite rotator in a waveguide.
`Faraday rotation The rotation of a signal’s polarization
`caused by its passage through the ionized E and F layers of
`the upper atmosphere.
`.
`_
`Faraday rotation isolator An isolator for. circular wave-
`guides that passes waves traveling in one direction but not
`
`
`
`Faraday rotation isolator.
`
`167
`
`

`

`
`
`Faraday rotator phase shifter
`
`in the other direction. A ferrite rod is pOSitiOHEd between
`resistive vanes to rotate the plane of polarization of the
`waves 45°.W'1th appropriate rectangular-to-circular_transr-
`tions, the isolator will work with rectangular wavegmdes-
`Faraday rotator phase shifter A latching. reciprocal phase
`shifter that includes a Faraday rotator section and nonre-
`ciprocal quarter-wave plates at each end.
`It. includes a
`square ferrite-filled waveguide. An axial coil rs wound
`around the waveguide. and its magnetic field 15 completed
`outside the waveguide wall with ferrimagnetic yokes.
`Quarter-wave plates at each end convert energy in. the
`rectangular enclosure either to right- or left-hand Circu-
`larly polarized energy. depending on the direction of prop-
`agation. The energy phase is changed by a variable axial
`magnetic field supplied by the coil around the waveguide.
`See phase shrficr.
`Faraday shield
`1. An electrostatic shield placed between
`the primary and secondary windings of a transformer to
`reduce coupling capacitance and common-mode noise.
`2. An electrostatic shield made of open metal—wire mesh.
`3. A plastic bag with both outer surfaces metallized to
`protect delicate, BSD-sensitive components from damage
`or destruction from ESD. The shield provides electrostatic
`shielding while passing electromagnetic waves. It need not
`be grounded. Sec electrostatic shield.
`Faraday’s law The voltage induced in a circuit is propor-
`tional to the rate at which the magnetic flux linkages of the
`circuit are changing. Also called law of electromagnetic
`induction.
`
`fararlic etu'rent An intermittent and nonsymmetrical alter-
`nating current similar to that obtained from the secondary
`winding of an induction coil.
`fanend crosstalk Crosstalk that travels along the dis-
`turbed circuit in the same direction as desired signals in
`that circuit. When it occurs at carrier telephone repeater
`stations, the output signals of one repeater go out also over
`the output line for the other repeater.
`far field The radiation field in the Fraunhofer region sur-
`rounding a transmitting antenna.
`far region Fraunhofer region.
`far zone Frannhofer region.
`fast Fourier transform [FFI'] A Fourier transform method
`for calculating the frequency spectrum, in both magnitude
`and angle, for any function of time by means of special
`operating programs that speed machine computation of
`complex Fourier series.
`fathometer Depth sounder:
`fault
`1. A defect such as an open circuit, short circuit, or
`inadvertent ground in a component, circuit, or transmis-
`sion line.
`2. A defect in a semiconductor device that can
`
`cause the device to fail during normal operation. It is usu-
`ally the result of a processing defect.
`fault mode current The current in a circuit under fault
`conditions, such as during arcbacks and load short-circuits.
`fault simulation This term usually means computer simula-
`tion of processing defects in integrated-circuit fabrication.
`The circuit description is modified (faulted) to correspond
`to a processing defect, and the simulation is renm to deter-
`mine whether the test program would find this defect.
`FAX (or fax) Abbreviation for facsimile.
`fc Abbreviation for footcandle.
`FC-AL Abbreviation for fiber-channel arbitrated loop.
`
`Com,
`
`FC_C . Abbrevranon for Federal Commandant,“
`mrssrorr.
`FDCC Abbreviation for fonvard control chart
`FDDI Abbreviation for fiber distributed data :1cl.
`FDM Abbreviation for frequency-division mugfflface
`FDMA Abbreviation for
`frequency.
`lPier.
`division multiple.
`access.
`FDX Abbreviation for full-duplex transmission
`FEC Abbreviation for forward error correction.
`FED Abbreviation for field-emitter display
`'
`Federal Aviation Administration [FAA] An a fin
`ated by Congress in 1958, with full authority ovefbocy "F“
`itary and civilian airspace requirements
`th nul-
`Federal Communications Commission [FCC]
`A US. gov.
`.
`ernment agency responsrble for the following;
`1
`"111
`policy governing allocation of radiated emissions. (fr c
`quencies).
`2. Establishing owner eligibility fol- Comm:-
`cial radio and TV stations and their licensing,
`3. Th:
`qualification and licensing of amateur and professional
`radio and radar operators and electronic technicians.
`feed
`1. To supply a signal to the input of a circuit, trans.
`mission line, or antenna.
`2. That part of a radar antenna
`connected to or mounted on the end of the transmission
`line which radiates RF energy to the reflector or receiVes
`energy therefrom.
`feedback The return of a portion of the output of a circujt
`or device to its input. With positive feedback, the signal fed
`back is in phase with the input and increases amplification
`but can cause oscillation. With negative feedback, the sig-
`nal fed back is 180° out of phase with the input and
`decreases amplification but stabilizes circuit performance
`and tends to minimize noise and distortion.
`
`feedback amplifier An amplifier with a passive network
`that returns a portion of the output signal to its input in a
`way that changes the performance characteristics of the
`amplifier.
`feedback controller A circuit or element in a closed-loop
`system that controls the motor or other actuator in a
`closed loop system to correct an error signal.
`feedback control loop A control loop circuit that senses
`any deviation from the desired output level and changes
`the drive waveforms of the power switch to compensate
`for those changes.
`feedback control system Closed loop control system .
`feedback oscillator An oscillating circuit with an cmPh‘
`fier whose output is fed back in phase with . the mplit'
`Oscillation is maintained at a frequency determined by th:
`values of the reactive components in the amplifier 311‘”
`feedback circuits.
`
`feedback path The transmission path fl'O
`put signal to the loop feedback signal in a feed
`trol 100p.
`'es
`feedback regulator A feedback control system "ml “'5.
`.
`ertalfl 53'
`.
`.
`.
`-
`to maintain a prescribed relationship betwéén ‘3 Som