Vertex Standard VX-450 series Service Manual

VX-450 Series
UHF Band
Service Manual

Introduction

This manual provides the technical information necessary for servicing the VX-450 Series Transceiver.
Servicing this equipment requires expertise in handing
surface-mount chip components. Attempts by non-quali-
fied 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 transceiver. Each side of the board is
referred to by the type of the majority of components in-
stalled on that side ("Side A" or "Side B"). In most cases
one side has only chip components (surface-mount de-
vices), 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 micro-
processor design of the VX-450 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 inconsis-
tencies in the technical information would be appreciated.
This transceiver is 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
USA (NA) & Except EIA (CE) Models ...................... 2
Eia (Ce) Model .......................................................... 3
Exploded View & Miscellaneous Parts .........................4
16 key & 4 key Type ................................................... 4
Non key Type ..............................................................5
Parts List ..........................................................................6
Block Diagram ................................................................ 8
Version A & D ............................................................8
Version I & K ............................................................16
Circuit Description .......................................................24
Version A & D ..........................................................24
Version I & K ............................................................27
Vx-450 Series Uhf Band Service Manual
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Important Note

Contents
Alignment ...................................................................... 30
Board Units (Schematics & Layouts)
MAIN Unit (Version A & D) ................................... 44
16 key & 4 key Type ........................................... 44
Non key Type ...................................................... 53
MAIN-2 Unit (Version I & K) ................................. 59
16 key & 4 key Type ........................................... 59
Non key Type ...................................................... 62
Display Unit (16 key & 4 key Type) ........................ 65
Vertex Standard LMR, Inc.
©2015 Vertex Standard LMR, Inc.
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