Vertex Standard VX-920 Series Service Manual

VX-920 Series
UHF Band
Service Manual
©2005 VERTEX STANDARD CO., LTD.
Specifications ...................................................................................................................................................... 2
Exploded View & Miscellaneous Parts .......................................................................................................... 3
Block Diagram .................................................................................................................................................... 5
Circuit Description ............................................................................................................................................. 7
Alignment .......................................................................................................................................................... 11
Board Units (Schematics, Layouts & Parts)
Main Unit .................................................................................................................................................... 15
Display Unit ................................................................................................................................................ 37
Cable Unit.................................................................................................................................................... 43
EC033U90A
Introduction
This manual provides the technical information necessary for servicing the
VX-920 Series Transceiver.
Servicing this equipment requires expertise in handing 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 board in this
transceiver. Each side of the board is referred to by the type of the majority of
components installed on that side ("Side A" or "Side B"). In most cases one
side has only chip components (surface-mount devices), and the other has
either a mixture of both chip and leaded components (trimmers, coils, elec-
trolytic capacitors, ICs, etc.), or leaded components only.
As described in the pages to follow, the advanced microprocessor design of
the VX-920 Series Transceiver allows a complete alignment of this transceiver
to be performed without opening the case of the radio; all adjustments can
be performed from the front panel, using the "Alignment Mode" menu.
While we believe the information in this manual to be correct, VERTEX STAN-
DARD assumes no liability for damage that may occur as a result of typo-
graphical or other errors that may be present. Your cooperation in pointing
out any inconsistencies in the technical information would be appreciated.
VERTEX STANDARD CO., LTD.
4-8-8 Nakameguro, Meguro-Ku, Tokyo 153-8644, Japan
VERTEX STANDARD
US Headquarters
10900 Walker 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
1