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2、eriesIIpreampshavebeencomingbackseveraltimeswiththesameproblem,itisevidentthatthepropercorrectiveactionhasnotbeentaken.Thisbulletinisprovidedtoassistthetechnicianinexpiditingandassuringalastingrepair.fig.1SlOESHOWNlI.JIIOurexperiencehasshownthatthesevenrelays(K7-9&KIO-13)circledinfig.1havethehighest
3、failurerate.Theseshouldbereplacedautomaticallywiththenewstylerelay,partno.129-0064(seesvc.bulletin10July1980).Installrelayregulatoraspersvc.bulletin#5199.L.;,J-_.0)iee:.QWIP.-5V.aD,IL:J,.c,(t;CorrectiveAction:Detection:Driveinputswithanappropriatesignallevel(phono5mV,highlevel150mV200-500Hz.).Monito
4、rmainoutputsbothchannels.Selectfunction.Taprelaythatselectsinputfunctionwithproblem.Watchforpartialorcompletedrop-outofoneorbothchannels.(Pleasenotethatevena goodrelaywilldrop-outmomentarilywhenbeaten.)Repeatdetectionprocessforallselectorinputs.Seattle-First National Bank, International Banking Divi
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