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                                                                      EXHIBIT 4
   
                                                         CONFORMED COPY

                      AMENDMENT NO. 4 TO CREDIT AGREEMENT

        AMENDMENT dated as of October 18, 1996 among LITTON INDUSTRIES, INC.
(the "Borrower"), the BANKS listed on the signature pages hereof (the "Banks"),
MORGAN GUARANTY TRUST COMPANY OF NEW YORK, as Agent (the "Agent") and WELLS
FARGO BANK, N.A., as Co-Agent (the "Co-Agent").

                             W I T N E S S E T H :

        WHEREAS, the parties hereto have heretofore entered into an Amended and
Restated Credit Agreement dated as of December 22, 1994 (as heretofore amended,
the "Agreement") and desire to amend the Agreement as set forth herein;

        NOW, THEREFORE, the parties hereto agree as follows:

        SECTION 1.  Definitions; References.  Unless otherwise specifically
defined herein, each term used herein which is defined in the Agreement shall
have the meaning assigned to such term in the Agreement.  Each reference to
"hereof", "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Agreement shall from and after the date hereof refer to the
Agreement as amended hereby.

        SECTION 2.  Amendments of Leverage Ratio Covenant and Related
Definitions.  (a) The definition of "Leverage Ratio" contained in Section 1.01
of the Agreement is amended to read in full as follows:

        "Leverage Ratio" means, at any date, the ratio of Total Borrowed Funds
    at such date to Consolidated EBITDA for the period of the four fiscal
    quarters most recently ended on or prior to such date.

        (b)  The following definition of "Consolidated EBITDA" is hereby added
to Section 1.01 of the Agreement immediately after the definition of
"Consolidated EBIT" and before the definition of "Consolidated Interest 
Expense":

        "Consolidated EBITDA" means, for any period, the Consolidated Net
    Income of the Borrower and its Consolidated Subsidiaries for such period
    before cumulative effect of accounting changes, provision for income tax,
    interest expense and depreciation and amortization expense.



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        (c)  Section 1.01 of the Agreement is further amended by deleting
therefrom the definition of "Consolidated Net Worth".

        (d)  Section 5.05 of the Agreement is amended to read in full as
follows:

             SECTION 5.05.  Leverage Ratio.  The Leverage Ratio will at no
    time exceed 250%.

        SECTION 3.  Representations and Warranties.  The Borrower hereby
represents and warrants that as of the date hereof and after giving effect
hereto:

        (a)  no Default under the Agreement has occurred and is continuing; and

        (b)  each representation and warranty of the Borrower set forth in the
    Agreement is true and correct as though made on and as of this date.

        SECTION 4.  Governing Law.  This Amendment shall be governed by and
construed in accordance with the laws of the State of New York.

        SECTION 5.  Counterparts; Conditions to Effectiveness.  This Amendment
may be signed in any number of counterparts, each of which shall be an
original, with the same effect as if the signatures thereto and hereto were
upon the same instrument.  This Amendment shall become effective as of the date
hereof when the Agent shall have received duly executed counterparts hereof
signed by the Borrower and the Required Banks (or, in the case of any party as
to which an executed counterpart shall not have been received, the Agent shall
have received telegraphic, telex or other written confirmation from such party
of execution of a counterpart hereof by such party).




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        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first above written.

                                        LITTON INDUSTRIES, INC.

                                        By:  /s/ Timothy G. Paulson
                                           ----------------------------------
                                           Title: Vice President & Treasurer

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                                        MORGAN GUARANTY TRUST COMPANY
                                          OF NEW YORK, as Bank and Agent


                                        By:  /s/ Diana H. Imhof
                                           ----------------------------------
                                           Title: Vice President


                                        BANK OF AMERICA NATIONAL TRUST AND
                                          SAVINGS ASSOCIATION


                                        By:  /s/ Lori Y. Kannegieter
                                           ----------------------------------
                                           Title: Managing Director         


                                        THE BANK OF NEW YORK


                                        By:  /s/ Craig J. Rethmeyer
                                           ----------------------------------
                                           Title: Vice President 


                                        THE CHASE MANHATTAN BANK


                                        By:  /s/ Richard C. Smith  
                                           ----------------------------------
                                           Title: Vice President            


                                        UNION BANK OF SWITZERLAND


                                        By:  /s/ Christopher W. Criswell
                                           ----------------------------------
                                           Title: Managing Director         

                                        By:  /s/ Daniel R. Strickford
                                           ----------------------------------
                                           Title: Assistant Vice President 












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                                        WELLS FARGO BANK, N.A.,
                                          as Bank and Co-Agent


                                        By:  /s/ Daniel H. Hom
                                           ----------------------------------
                                           Title: Vice President


                                        THE BANK OF NOVA SCOTIA


                                        By:  /s/ Maarten Van Otterloo
                                           ----------------------------------
                                           Title: Senior Relationship
                                                    Manager


                                        CIBC INC.


                                        By:  /s/ Robert J. Wagner
                                          ----------------------------------
                                          Title: Agent


                                        CREDIT SUISSE


                                        By:  /s/ Stephen M. Flynn
                                           ----------------------------------
                                           Title: Member of Senior Management

                                        By:  /s/ Deborah A. Shea
                                           ----------------------------------
                                           Title: Associate


                                        DRESDNER BANK AG, NEW YORK, BRANCH
                                          AND GRAND CAYMAN BRANCH


                                        By:  /s/ John W. Sweeney
                                           ----------------------------------
                                           Title: Assistant Vice President
                                                    Credit Administration

                                        By:  /s/ Thomas J. Nadramia
                                           ----------------------------------
                                           Title: Vice President 







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                                        MELLON BANK, N.A.


                                        By:  /s/ Stephen P. Yost
                                           ----------------------------------
                                           Title: First Vice President


                                        NATIONSBANK OF TEXAS, N.A.


                                        By:  /s/ Michael F. Shea
                                           ----------------------------------
                                           Title: Vice President


                                        THE FIRST NATIONAL BANK OF CHICAGO


                                        By:  /s/ Paul C. Hennessy
                                           ----------------------------------
                                           Title: Senior Vice President


                                        THE NORTHERN TRUST COMPANY


                                        By:  /s/ Michelle D. Griffin
                                           ----------------------------------
                                           Title: Vice President 


                                        TORONTO DOMINION (TEXAS), INC.


                                        By:  /s/ Federic Hawley
                                           ----------------------------------
                                           Title: Vice President


                                        BANK OF HAWAII


                                        By:  /s/ Susan McCarthy
                                           ----------------------------------
                                           Title: Assistant Vice President