Vertex Standard VX-820 Series Service Manual

VX-820/-820E Series
UHF Band
Service Manual
©2009 VERTEX STANDARD CO., LTD.
Introduction
This manual provides the technical information necessary for servicing the VX-820 Series Transceiver.
Servicing this equipment requires expertise in handing surface-mount chip com-
ponents. Attempts by non-qualified persons to service this equipment may re-
sult 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, electrolytic ca-
pacitors, ICs, etc.), or leaded components only.
As described in the pages to follow, the advanced microprocessor design of the
VX-820 Series Transceiver allows a complete alignment of this transceiver to be
performed without opening the case of the radio; all adjustments can be per-
formed 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 typographi-
cal or other errors that may be present. Your cooperation in pointing out any
inconsistencies in the technical information would be appreciated.
After Lot. 11 of this 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 apparatus. 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.
Specifications........................................................... 2
Exploded View & Miscellaneous Parts ................. 4
Block Diagram ........................................................ 5
Circuit Description ................................................ 7
Alignment ................................................................9
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 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
VERTEX STANDARD ( AUSTRALIA ) PTY., LTD.
Normanby Business Park, Unit 14/45 Normanby Road
Notting Hill 3168, Victoria, Australia
EC058U90D
Important Note
Contents
Board Units (Schematics, Layouts & Parts)
MAIN Unit ....................................................... 15
Display Unit ..................................................... 47
Cable Unit ........................................................ 64
1