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                                                           EXHIBIT 4.1


The Corporation is authorized to issue more than one class of stock. Upon
written request, made by the holder of this Certificate, the Corporation will
furnish to such holder without charge a copy of the full text of the
preferences, voting powers, qualifications and special and relative rights of
the shares of each class authorized to be issued, as set forth in the
Certificate of Incorporation and the votes of the Board of Directors.

The following abbreviations, when used in the inscription on the face of this
certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

TEN COM
TEN ENT
JT TEN

-
-
-

as tenants in common
as tenants by the entireties
as joint tenants with right of
survivorship and not as tenants
in common

UNIF GIFT MIN ACT-.........................Custodian........................
(Minor)                                                                   (Cust)
                                        under Uniform Gifts to Minors
                                       Act........................
                                                                 (State)

Additional abbreviations may also be used though not in the above list.

Important Notice: When you sign your name to this Assignment Form without
filling in the name of your "Assignee" or "Attorney", this stock certificate
becomes fully negotiable, similar to a check endorsed in blank. Therefore, to
safeguard a signed certificate, it is recommended that you either (i) fill in
the name of the new owner in the "Assignee" blank, or (ii) if you are sending
the signed certificate to your bank or broker, fill in the name of the bank or
broker in the "Attorney" blank. Alternatively, instead of using the Assignment
Form, you may sign a separate "stock power" form and then mail the unsigned
stock certificate and the signed "stock power" in separate envelopes. For added
protection, use certified or registered mail for a stock certificate.

For value received,      hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

shares of the capital stock represented by the within Certificate, and do

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hereby irrevocably constitute and appoint

Attorney

to transfer the said stock on the books of the within named Corporation
with full power of substitution in the premises.
Dated

NOTICE:

THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON
THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR
ENLARGEMENT OR ANY CHANGE WHATEVER.

SIGNATURE(S) GUARANTEED:

THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION
(BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH
MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO
S.E.C. RULE 17Ad-15.


This certificate also evidences and entitles the holder hereof to certain rights
as set forth in a Rights Agreement between Signal Technology Corporation and
BankBoston, N.A., dated as of January 26, 1999 (the "Rights Agreement"), the
terms of which are hereby incorporated herein by reference and a copy of which
is on file at the principal executive offices of Signal Technology Corporation.
Under certain circumstances, as set forth in the Rights Agreement, such Rights
may be redeemed, may expire, or may be evidenced by separate certificates and
will no longer be evidenced by this certificate. Signal Technology Corporation
will mail to the registered holder of this certificate a copy of the Rights
Agreement without charge after receipt of a written request therefor. As
described in the Rights Agreement, under certain circumstances, Rights held by
Acquiring Persons (as defined in the Rights Agreement), or certain related
Persons, and any subsequent holder of such Rights, may become null and void.

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FBU

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

SEE REVERSE FOR CERTAIN DEFINITIONS

CUSIP 826675 10 0

THIS STOCK IS TRANSFERABLE IN BOSTON,
MASSACHUSETTS OR NEW YORK,  NEW YORK



THIS CERTIFIES THAT



is the owner of

FULLY PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK, $.01 PAR VALUE, OF

SIGNAL TECHNOLOGY CORPORATION

transferable only on the books of the Corporation by the holder hereof in person
or by duly authorized attorney upon surrender of this Certificate properly
endorsed. This Certificate and the shares represented hereby are issued under
and subject to the laws of the State of Delaware and to the Certificate of
Incorporation and By-Laws of the Corporation, all as in effect from time to
time. This Certificate is not valid until countersigned and registered by the
Transfer Agent and Registrar.

WITNESS the facsimile seal of the Corporation and the facsimile signatures of
its duly authorized officers.

Dated


CHAIRMAN AND CHIEF EXECUTIVE OFFICER

VICE PRESIDENT FINANCE, TREASURER AND
CHIEF FINANCIAL OFFICER

COUNTERSIGNED AND REGISTERED:
BankBoston, N.A.
TRANSFER AGENT
AND REGISTRAR
BY


AUTHORIZED SIGNATURE