1IntroductionThis manual provides technical information necessary for servicing the FT-1900R FM Transceiver.Servicing this equipment requires expertise in handling surface-mount chip components. Attempts by non-qualified persons to service this equipment may result in permanent damage not covered by the warranty,and may be illegal in some countries.Two PCB layout diagrams are provided for each double-sided circuit board in the Transceiver. Each side ofis referred to by the type of the majority of components installed on that side (“leaded” or “chip-only”). Inmost cases one side has only chip components, and the other has either a mixture of both chip and leadedcomponents (trimmers, coils, electrolytic capacitors, ICs, etc.), or leaded components only.While we believe the technical information in this manual to be correct, VERTEX STANDARD assumes noliability for damage that may occur as a result of typographical or other errors that may be present. Yourcooperation in pointing out any inconsistencies in the technical information would be appreciated.©2009 VERTEX STANDARD CO., LTD. EH023N91ATechnical SupplementSpecifications ...................................................... 2Exploded View & Miscellaneous Parts ............ 3Block Diagram .................................................... 5Connection Diagram .......................................... 6Circuit Description............................................. 7Alignment ............................................................ 9ContentsBoard Unit ( Schematics, Layouts & Parts )MAIN Unit Circuit Diagram ................................. 13MAIN Unit Parts Layout ...................................... 15MAIN Unit Parts List ............................................ 17CNTL Unit Circuit Diagram .................................. 27CNTL Parts Layout ............................................... 28CNTL Parts List .................................................... 29FM TRANSCEIVERFT-1900RVERTEX STANDARD CO., LTD.4-8-8 Nakameguro, Meguro-Ku, Tokyo 153-8644, JapanVERTEX STANDARDUS Headquarters10900 Walker Street, Cypress, CA 90630, U.S.A.YAESU UK LTD.Unit 12, Sun Valley Business Park, Winnall CloseWinchester, Hampshire, SO23 0LB, U.K.VERTEX STANDARD HK LTD.Unit 5, 20/F., Seaview Centre, 139-141 Hoi Bun Road,Kwun Tong, Kowloon, Hong KongVERTEX STANDARD (AUSTRALIA) PTY., LTD.Normanby Business Park, Unit 14/45 Normanby RoadNotting Hill 3168, Victoria, AustraliaImportant NoteThe transceiver was assembled using Pb (lead) free solder, based on the RoHS specification.Only lead-free solder (Alloy Composition: Sn-3.0Ag-0.5Cu) should be used for repairs performed on this appara-tus. The solder stated above utilizes the alloy composition required for compliance with the lead-free specification,and any solder with the above alloy composition may be used.