Yaesu VR-120D Technical Supplement

COMMUNICATIONS RECEIVER
VR-120D
Technical Supplement
©2002 VERTEX STANDARD CO., LTD. Printed in Japan.
Introduction
This manual provides technical information necessary for
servicing the Yaesu VR-120D Communications Receiver.
Information on its installation and operation can be found
in the VR-120D Operating Manual, which is provided with
the receiver, and Accessory information may be found in
the documents accompanying the optional equipment.
The VR-120D is a high-performance miniature
communications receiver providing general coverage
reception from 100 kHz to 1300 MHz on the AM, and FM
(Wide and Narrow bandwidths) modes (this coverage
includes the AM and FM broadcast bands, HF Short-wave
Bands up to 16 MHz, VHF and UHF TV bands, the VHF
AM aircraft band, and a wide range of commercial and
public safety frequencies!).
Servicing this equipment requires expertise in handling
surface mount chip components. Attempts by unqualified
persons to service this equipment may result in permanent
damage not covered by warranty. For the major circuit
boards, each side of the board is identified by the type of
the majority of components installed on that side. In most
cases one side has only chip components, and the other
has either a mixture of both chip and lead components
(trimmers, coils, electrolytic capacitors, packaged ICs, etc.),
or lead components only.
Specifications ............................................................................................................................................... 2
Exploded View & Miscellaneous Parts ..................................................................................................... 3
Circuit Description ...................................................................................................................................... 5
Alignment ..................................................................................................................................................... 7
Block Diagram .............................................................................................................................................13
Board Unit (Schematics, Layouts & Parts)
CNTL AF Unit ........................................................................................................................................................ 15
•
RF Unit .................................................................................................................................................................... 23
EH011M90A
While we believe the technical information in this manual
is 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. VERTEX STANDARD
reserves the right to make changes in this receiver and the
alignment procedures, in the interest of technological
improvement, without notification of owners.
Contents
VERTEX STANDARD CO., LTD.
4-8-8 Nakameguro, Meguro-Ku, Tokyo 153-8644, Japan
VERTEX STANDARD
US Headquarters
17210 Edwards Rd., Cerritos, CA 90703, U.S.A.
International Division
8350 N.W. 52nd Terrace, Suite 201, Miami, FL 33166, 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
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