Instrument for measuring various electrical quantities including voltage, current and resistance

multitrack/'тлШ.ггаек/ [6] sound recording in which the different sounds which make up the recording are recorded on separate tracks

music centre /'mju:zik ,senta(r)/ [13] unit containing a combination of sound reproduction devices such as a tape deck, a radio tuner, a CD player, an amplifier, loudspeakers etc.

mW /'miliwots/ [11] milliwatt (thousandths of a watt): measure of power

N

NAND gate /'naend geit/ [23] digital logic

gate which has a high output unless all its

Inputs are high natural frequency /.Naetjaral 'fri:kwansi/

see resonant frequency neon lamp /,ni:on 'laemp/ [5] electrical

component which gives off light when a

Voltage ionizes the neon gas inside network /'netw3:k/ [26] system of

Interconnected devices network manager /,netw3:k 'тгепк1зэ(г)/

[29] person in charge of the operation of a

computer network NiCad /'nikeed/ [5] nickel cadmium (NiCd):

chemical used is some batteries noise /noiz/ [8, 13] see interference noisy /'пот/ [28] affected by unwanted

signals

NOT gate /'not geit/ [23] digital logic gate which has a high output when its input is low and vice versa

NPN transistor /en pi: 'en tra3n,zista(r)/ [1, 11] type of transistor made from a thin layer of P-type semiconductor material between two thicker layers of N-type semiconductor material

ohm /'эит/ [1] unit of resistance (Q) ohmmeter /'9ummi:t9(r)/ [19] electronic

instrument for measuring resistance op amp /'op гетр/ [1] see operational

amplifier open /'эирп/ [11] unconnected operational amplifier /.opsreijonl

'asmplifaia(r)/ [ 1 ] an extremely high gain

analogue 1С amplifier optical fibre /.optikl 'faiba(r)/ [26, 28]

strand of silica for guiding light waves optical flatness /, optikl 'flaetnas/ [6] flat

enough to give accurate deflection of light optoelectronics /.optauelek'troniks/ [2]

the study and use of optical components in

electronics

OR gate /э:(г) geit/ [23] digital logic gate

which has a high output when any of its

inputs are high oscillate /'Dsileit/ [10] move backwards

and forwards between two different states oscillator /'Ds[Ieit9(r)/ [1] electronic circuit

which produces a repeating signal oscilloscope /D'silaskaup/ [19] see

cathode ray oscilloscope outer space /auta 'speis/ [10] region

beyond the earth's atmosphere output /'autput/ n [1] signal coming out of

a circuit

page /рек!з/ v [27] send a signal to indicate

that a message is waiting to be

communicated pager/'peid33(r)/ [28, 30] see radiopager paging system /'peid3irj,sistam/ [30]

mobile communications system which

uses pager devices to contact people panning /'paenirj/ [15] steady movement of

the apparent source of sound across an

area

parallel wire cable /.paeralel 'waia ,keibl/ [26] transmission line consisting of two wires running side-by-side and covered by an insulating material

passive infra-red detector /paesiv infra'red di,tekta(r)/ [9] device which detects the presence of heat given off by a body

PCB /,pi: si: 'bi:/ printed circuit board

PCM /pi: si: 'em/ [26] pulse code modulation: modulation system which sends a differently coded train of pulses to represent each size of sampled signal

PD /pi: 'di:/ potential difference: see voltage drop

peak point /'pi:k paint/ [18] highest turning value on a curved graph

permeability /p3:mia'bilati/ [19] property of a material which measures the ratio of flux density to magnetic field strength

personal stereo /,p3:sanl 'stenao/ [18] small portable cassette tape player with stereo sound designed for use by one person

perspex /'p3:speks/ [6, 16] tough

transparent plastic material used to make

compact discs phone /faun/ [26, 28] see telephone phones /faunz/ [28] see headphones phono socket /'faunau ,sokit/ [22]

common type of connector used on audio

devices

phosphor /'fosfa(r)/ [19] metal compound which gives off light when hit by a stream of electrons

photodiode /.fautau 'daiaud/ [4,8] semiconductor which is sensitive to light causing a reverse current to flow when light shines on it

photoresist /fautaun'zist/ [6, 17] chemical lacquer which is sensitive to light and is used in making compact discs and printed circuit boards

picofarad /pikau'faerad/ [1] 10"⁹ of a farad (pF): measure of capacitance

piezoelectric crystal /,pi:zauilektrik 'kristal/ see quartz crystal

pin /pin/ [19] input or output connector of an 1С chip

pin-out diagram /pinaut 'daiagraem/ [23]

diagram showing the function and signal

level of each pin of an 1С chip pit /pit/ [6, 16] hollow area produced on the

surface of a compact disc by a laser beam pitch /pitj^-/ [28] frequency level plate /pleit/ American term for anode playback /'pleibaek/ [7] playing of a

recording PN junction /pi: en ^злпкГэп/ [18]

surface where a layer of N-type and a layer

of P-type semiconductor meet PNP transistor /pi: en 'pi: traen'zista(r)/

[1, 11] type of transistors made from a thin

layer of N-type semiconductor material

between two thicker layers of P-type

semiconductor material pole /paul/ [5] positive or negative terminal polyethylene /poli'e9ali:n/ [26]

translucent plastic insulating material

used as a dielectric in coaxial cable polythene /'polaBi-'n/ see polyethylene Portastudio /'po:ta,stju:diau/ [7] portable

recording studio pot /pot/ [1] see potentiometer potential difference /pa.tenjl difrans/

see voltage drop potential divider /pa.tenfl di'vaida(r)/ [9]

part of an electronic circuit which divides a

voltage into two or more smaller parts potentiometer/pa.tensi'DmitaCrVtl]

variable electronic component for dividing

a voltage into two smaller parts power amp /'pauar aemp/ [1, 13] see power

amplifier

power amplifier /'pauar ,aemplifaia(r)/ [13] electronic circuit used to increase the power of audio signals to enable them to drive loudspeaker systems

power cut /'раиэ клг./ [9] sudden failure of the main power supply

power dissipation /'раиэ .disi.perjn/ [23] gradual release of energy over a period of time

power rating /'раиэ .reitin/ [18] manufacturer's recommended maximum operating power for a component

power transistor /'раиэ traen,zist9(r)/ [13] large transistor used in a power amplifier for increasing the power of a signal

pre-amp /'priiaemp/ [11] see preamplifier preamplifier /pri:'smpli,faia(r)/ [13]

electronic circuit used to increase audio

signal voltage

preferred values /pn'f3:d ,vaelju:z/ [4] set of standard values from which all other values can be produced

pressure mat /'prefa maet/ [9] rubber mat switch used in alarm systems to detect a change of pressure caused by someone stepping on the mat

primary /'praimari/ n [5] transformer input coil

primary cell /praimari 'sel/ [5] energy

source which cannot be recharged printed circuit /.pnntid 's3:krt/ [14] circuit

with conductors printed and etched on a

copper board program /'ргэидгэет/ n [23] set of

instructions for controlling a computer programme /'ргэидгагт/ n [20] television/

radio show programmer /'ргэодгаетэ(г)/ [29] person

who writes computer programs propagation /'propa.geijn/ [10]

movement of a signal through a medium

such as air or water PSTN /.pi: es ti: 'en/ [28] Public Switching

Telephone Network Public Switching Telephone

Network /,рлЫ1к .switfirj 'telsfaun

,netw3:k/ [28] national system of