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                                                                     EXHIBIT 3.1
                               State of Delaware

                   Office of the Secretary of State   PAGE 1         

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     I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY 
CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF AMENDMENT 
OF "DATAMETRICS CORPORATION", FILED IN THIS OFFICE ON THE TWENTY-SEVENTH DAY OF 
JUNE, A.D. 1997, AT 9 O'CLOCK A.M.











       [Logo of Office of Secretary of State] 
                                       
                                      /s/ Edward J. Freel
                                     ------------------------------------
                                      Edward J. Freel, Secretary of State

                                      AUTHENTICATION:   8794918
                                                DATE:   12/05/97               
                                        
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                           CERTIFICATE OF AMENDMENT
                                      OF 
                         CERTIFICATE OF INCORPORATION
                          OF DATAMETRICS CORPORATION 

     Datametrics Corporation, a corporation duly organized and existing under 
the General Corporation Law of the State of Delaware (the "Corporation"), does 
                                                           -----------
hereby certify as follows:

     1.     The amendments to the Corporation's Certificate of Incorporation set
forth below were duly adopted in accordance with the provisions of Section      
242 of the General Corporation Law of the State of Delaware and have been duly 
approved by the vote of the holders of a majority of the outstanding shares of 
the Corporation's stock entitled to vote, in accordance with Section 211 of the 
General Corporation Law of the State of Delaware.

     2.     The name of the Corporation is Datametrics Corporation and the 
original Certificate of Incorporation of the Corporation was filed with the 
Secretary of State of the State of Delaware on September 5, 1980.

     3.     Article FOURTH of the Corporation's Certificate of Incorporation is 
amended to read in its entirety as follows:

            FOURTH:   The Corporation is authorized to issue two classes of 
            ------
            shares of capital stock to be designated respectively,  "Preferred 
            Stock" and "Common Stock."  The total number of shares which the 
            Corporation is authorized to issue is forty-five million 
            (45,000,000).  Five million (5,000,000) shares shall be Preferred 
            Stock and forty million (40,000,000) shares shall be Common Stock.  
            The Preferred Stock and the Common Stock shall each have a par value
            of $.01.  The aggregate par value of all shares of Preferred Stock 
            is $50,000 and the aggregate par value of all shares of Common Stock
            is $400,000.

     4.     Article SIXTH of the Corporation's Certificate of Incorporation is 
amended to read in its entirety as follows:

            SIXTH:        (a)   The number of directors which shall
            -----     
            constitute the whole Board of Directors of the Corporation shall
            be as specified in the By-Laws of the Corporation.          






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                            (b)   The Board of Directors of the Corporation
shall be divided into three classes as nearly equal in number as possible,
hereby designated as Class I, Class II and Class III. The term of office of the
initial Class I directors shall expire at the next succeeding annual meeting of
the stockholders of the Corporation; the term of office of the initial Class II
directors shall expire at the second succeeding annual meeting of the
stockholders of the Corporation; and the term of office of the initial Class III
directors shall expire at the third succeeding annual meeting of the
stockholders of the Corporation. For the purposes hereof, the initial Class I,
Class II and Class III directors shall be those directors elected at the 1997
annual meeting of the stockholders of the Corporation and designated as members
of each such class, respectively. At each annual meeting of the stockholders of
the Corporation after the 1997 annual meeting, directors to replace those of a
class whose terms expire at such annual meeting shall be elected to hold office
until the third succeeding annual meeting and until their respective successors
shall have been duly elected and qualified. If the number of directors is
hereafter increased, the directors then in office shall select the class or
classes to which the newly created directorships shall be assigned so as to make
all classes as nearly equal in number as possible.

                            (c)   Notwithstanding anything to the contrary
contained in the Certificate of Incorporation of the Corporation, the number of
directors may be increased or decreased from time to time only by the
affirmative vote of the holders of at least seventy-five percent (75%) of the
outstanding shares of voting stock of the Corporation or with the approval of a 
majority of directors of the Corporation then in office, provided
that in no event shall the number of directors be fewer than five nor more than
nine.

                            (d)   Notwithstanding anything to the contrary
contained in the Certificate of Incorporation of the Corporation, the
affirmative vote of the holders of at least seventy-five percent (75%) of the
outstanding shares of voting stock of the Corporation shall be required to
alter, amend, repeal or adopt any provision inconsistent with this Article
SIXTH.

     IN WITNESS WHEREOF, Datametrics Corporation has caused this Certificate of 
Amendment to be executed by its authorized officer on this 30th day of May, 
1997.


                              /s/ Daniel P. Ginns
                              -------------------
                              Daniel P. Ginns
                              Chairman of the Board and Chief Executive Officer

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