YAESU–FT-747-维修电器原理图手册

FT-74TGX TECHNICAL SUPPLEMENTCONTENTST0 P COVER REMOVAL,,,,。·····:·····,·······2EXPL0 DED VIEW。··。·。·····,·。··,······,·3MAIN UNITParts LayoutCircuit Diagram5Parts LayoutCireuit Diagram77NB UNITPart移ayauCireuit DlagramL0 CAL UNIT·,·,··,····8Parts LayoutCireuit Dlagram100 W PA UNIT···,,9Parts Layout10Cireuit DtagramLPF UNIT10Parts Layout11CIrcuit DiagramI1Parts Layeut12Circult DiagramThis marual is Incended to serve as a supplement to the FT-747GX Operating Masusl.De-13CONNECTION DIAGRAM,,,:。····,,·····,·····,,·14talled Information regarding fanctions,Installation.interconneetions and operation has beenprovided in the Operating Manual,and is not reprinted herein.Therefore,this supplement Isnot intended to serve as an Iadependent referesce,but to be used in conjusctioe with theTransmit15information provided in the Operating Marual.RecelveSIGNAL PATH16Because there are nearly two hundred and fifty semiconductor devices in the FT-747GX,SSB MODEciresit description Informatloe provided in the form of numerous block diagrams.We hopeCW MODEthat this manner of providing functional informstion proves to be more comenie=t for theAM MODEowner and technicias than would a lengthy verbal descripeian.Those readers unfamiliar withFM MODEthe basie types of anslog and digital cireuits that serve as the bullding blocks of the FT.747GX are encouraged to stady instructional matertal,such as that provided in handbooks onI.Local Uaitamateur radio and digital circult design,before attempting to understand the design of the1.23Maln Unit ReceiverFT-747GX.Esch block in the block diagrams represents one such hasic ciroait.General infor-24Main Unit Transmittermation on integrated circuits and ther applications ss mrailable in the data provided by theV26Noise Blanker UnitIC manufacturers.Speeifie circutt detalls are provided in the sehematie diagrams in this2100W PA Unit Idling CurrentVL.2LPF Unit ICM Coupler Balance)Whlle we belleve the technical information in this manual is correet,Yaeu sumes noVI,28Maln Unit [AFP Automatic FInal Protectionl28liability fer damage that may occur asa result of typographieal or other errors that may bePART5uST·-,。····,,······,。·。··-29present.Your cooperation in pointing out any inconsistencies in the technical infurmationwould be appreciated.Yaesu Musen reserves the right to make changes in the circuitry of this traaseeiver,in.theinterest of technological tmprovement,without obligation to notify owners or to modify any线rnh.ced prior切the modi自cation.-1