Vertex Standard VX-920 Series Service Manual

VX-920/-920E Series
UHF Band
Service Manual
©2010 VERTEX STANDARD CO., LTD.
After Lot.12 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 .......................................................................................................... 3
Block Diagram .................................................................................................................................................... 5
Circuit Description ............................................................................................................................................. 7
Alignment .......................................................................................................................................................... 11
Board Units (Schematics, Layouts & Parts)
Main Unit .................................................................................................................................................... 15
Display Unit ............................................................................................................................................... 53
Cable Unit .................................................................................................................................................. 59
SRX-4 Unit (Option) ................................................................................................................................. 61
EC033U90E
This manual provides the technical information necessary for servicing the VX-920/
-920E Series Transceiver.
Servicing this equipment requires expertise in handing surface-mount chip compo-
nents. Attempts by non-qualified persons to service this equipment may result in per-
manent 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 trans-
ceiver. 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 capacitors, ICs, etc.), or
leaded components only.
As described in the pages to follow, the advanced microprocessor design of the VX-
920/-920E 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 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.
Important Note
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
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