1Quad Band FM TransceiverFT-8900RTechnical SupplementIntroductionThis manual provides technical information necessary for servicing the FT-8900R Transceiver.Servicing this equipment requires expertise in handling surface-mount chip components. Attempts by non-qualifiedpersons to service this equipment may result in permanent damage not covered by the warranty, and may be illegal insome countries.Two PCB layout diagrams are provided for each double-sided circuit board in the transceiver. Each side of thr board isreferred to by the type of the majority of components installed on that side (“leaded” or “chip-only”). In most cases oneside has only chip components, and the other has either a mixture of both chip and leaded components (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 no liability for damagethat may occur as a result of typographical or other errors that may be present. Your cooperation in pointing out anyinconsistencies in the technical information would be appreciated.Specifications .................................................... 2Exploded View & Miscellaneous Parts ........ 3Connection Diagram ........................................ 4Circuit Description ........................................... 5Alignment ........................................................ 11ContentsBoard Unit (Schematics, Layouts & Parts)Main Unit ..................................................................... 17Panel Unit ..................................................................... 47Panel-Sub Unit ............................................................. 53VR-L Unit ..................................................................... 55VR-R Unit ..................................................................... 56© 2002 VERTEX STANDARD CO., LTD. (EH008M90A)VERTEX STANDARD CO., LTD.4-8-8 Nakameguro, Meguro-Ku, Tokyo 153-8644, JapanVERTEX STANDARDUS Headquarters10900 Walker Street, Cypress, CA 90630, U.S.A.International Division8350 N.W. 52nd Terrace, Suite 201, Miami, FL 33166, U.S.A.YAESU EUROPE B.V.P.O. Box 75525, 1118 ZN Schiphol, The NetherlandsYAESU 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 Kong1 46523LOWSQL SQLVOL VOLLOW V/M HM SCNV/M HM SCNKEY2PWR