Yaesu FT-857 series Technical Supplement

Introduction

This manual provides technical information necessary for servicing the FT-857/-857D HF/VHF/UHF Ultra-Compact Trans-

ceiver.

Servicing this equipment requires expertise in handling surface-mount chip components. Attempts by non-qualified per-

sons 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 of is referred to

by the type of the majority of components installed on that side (“leaded” or “chip-only”). In most cases one side 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

damage that may occur as a result of typographical or other errors that may be present. Your cooperation in pointing out

any inconsistencies in the technical information would be appreciated.

©2005 VERTEX STANDARD CO., LTD.

EH007M90B

Technical Supplement

Specifications .................................................... 2

Exploded View & Miscellaneous Parts ....... 5

Connection Diagram ....................................... 7

Block Diagram .................................................. 8

Circuit  Description ......................................... 9

Alignment ........................................................ 12

Contents

Board Unit

 (Schematics, Layouts & Parts)

MAIN Unit ................................................................. 23

PLL Unit ..................................................................... 57

PA Unit ....................................................................... 67

PANEL Unit ............................................................... 81

REF Unit ..................................................................... 87

PHONE-JACK Unit ................................................... 88

VR Unit ....................................................................... 89

CONNECTOR Unit ................................................... 90

DSP-2 Unit (FT-857 Option) .................................... 91

CXO-9 Unit (Option) .............................................. 94

VERTEX STANDARD CO., LTD.

4-8-8 Nakameguro, Meguro-Ku, Tokyo 153-8644, Japan

VERTEX STANDARD

US Headquarters

10900 Wa ker Street, Cypress, CA 90630, U.S.A.

YAESU EUROPE B.V.

P.O. Box 75525, 1118 ZN Schiphol, The Netherlands

YAESU UK LTD.

Unit 12, Sun Valley Business Park, Winnall Close

Winchester, Hampshire, SO23 0LB, U.K.

VERTEX STANDARD HK LTD.

Unit 5, 20/F., Seaview Centre, 139-141 Hoi Bun Road,

Kwun Tong, Kowloon, Hong Kong

FT-857/-857D

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