tsüklilised orgaanilised ühendid (üldvalem C12H10-xClx), mida kõrge kuumataluvuse tõttu kasutati laialdaselt tehnikas (nt transformaatorites ja kondensaatorites); on püsivad, väga mürgised ja kantserogeensed ühendid, biomagnifitseeruvad toiduahelas

any of a number of derivatives of biphenyl (C6H5C6H5) in which some of the hydrogen atoms on the benzene rings have been replaced by chlorine atoms

printed circuit on rigid substrate, provided with multiple plug-in or other contact terminals and on which are mounted discrete devices, dielectric sheet (usually of filled resin) with a conducting layer (usually copper) on the surface, from which conducting paths of an electrical circuit are produced and onto which active and passive electronic components may be mounted, the board carrying a printed circuit, trükilülitus - lülitus, mille ühendusjuhid on moodustatud isoleerplaadile trükkimise abil