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                                                                     Exhibit 3.1

                      RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                        INSTRUMENT TECHNOLOGY CORPORATION

                 (The original Certificate of Incorporation was
                  filed with the Secretary of State of Delaware
                             on December 26, 1968.)

     FIRST. The name of the corporation is

                       INSTRUMENT TECHNOLOGY CORPORATION

     SECOND. The address of its registered office in the State of Delaware is
No. 100 West Tenth Street, in the City of Wilmington, County of New Castle. The
name of its registered agent at such address is The Corporation Trust Company.

     THIRD. The nature of the business or purposes to be conducted or promoted
is:

     To manufacture, produce, assemble, disassemble, fabricate, import, lease,
purchase or otherwise acquire, invest in, own, hold, use, license the use of,
install, handle, maintain, service, repair, recondition, certify for use under
government regulation, sell, pledge, mortgage, exchange, export, import, lease,
assign, dispose of, trade, and deal in and with air-planes, aircraft parts and
equipment, navigation, electronic, electrical, electro-mechanical,
telecommunication, communication, microwave telephone, radio, sonar, and radar
and television devices, equipment, components, supplies, parts, apparatus
appliances, tools and machinery.

     To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

     To manufacture, purchase or otherwise acquire, invest in, own, mortgage,
pledge, sell, assign and transfer or otherwise dispose of, trade, deal in and
deal with goods, wares and merchandise and personal property of every class
and description.

     To acquire, and pay for in cash, stock or bonds of this corporation or
otherwise, the good will, rights, assets and property, and to undertake or
assume the whole or any part of the obligations or liabilities of any person,
firm, association or corporation.

     To acquire, hold, use, sell, assign, lease, grant licenses in respect of,
mortgage or otherwise dispose of letters patent of the United States or any
foreign country, patent rights, licenses and privileges, inventions,
improvements and processes, copyrights, trademarks and trade names, relating to
or useful in connection with any business of this corporation.

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     To acquire by purchase, subscription or otherwise, and to receive, hold,
own, guarantee, sell, assign, exchange, transfer, mortgage, pledge or otherwise
dispose of or deal in and with any of the shares of the capital stock, or any
voting trust certificates in respect of the shares of capital stock, scrip,
warrants, rights, bonds, debentures, notes, trust receipts, and other
securities, obligations, choses in action and evidences of indebtedness or
interest issued or created by any corporations, joint stock companies,
syndicates, associations, firms, trusts or persons, public or private, or by the
government of the United States of America, or by any foreign government, or by
any state, territory, province, municipality or other political subdivision or
by any governmental agency, and as owner thereof to possess and exercise all the
rights, powers and privileges of ownership, including the right to execute
consents and vote thereon, and to do any and all acts and things necessary or
advisable or the preservation, protection, and improvement of the value
thereof.

     To borrow or raise moneys for any of the purposes of the corporation
from time to time without limit as to amount, to draw, make, accept, endorse,
execute and issue promissory notes, drafts, bills of exchange, warrants, bonds,
debentures and other negotiable or non-negotiable instruments and evidences of
indebtedness, and to secure the payment of any thereof and of the interest
thereon by mortgage upon or pledge, conveyance or assignment in trust of the
whole or any part of the property of the corporation, whether at the time owned
or thereafter acquired, and to sell, pledge or otherwise dispose of such bonds
or other obligations of the corporation for its corporate purposes.

     To purchase, receive, take by grant, gift, devise, bequest or otherwise,
lease, or otherwise acquire, own, hold, improve, employ, use and otherwise deal
in and with real or personal property, or any interest therein, wherever
situated, and to sell, convey, lease, exchange, transfer or otherwise dispose
of, or mortgage or pledge, all or any of the corporation's property and assets,
or any interest therein, wherever situated.

     In general, to possess and exercise all the powers and privileges granted
by the General Corporation Law of Delaware or by any other law of Delaware or by
this certificate of incorporation together with any powers incidental thereto,
so far as such powers and privileges are necessary or convenient to the conduct,
promotion or attainment of the business or purposes of the corporation.

     The business and purposes specified in the foregoing clauses shall, except
where otherwise expressed, be in nowise limited or restricted by reference to,
or inference from, the terms of any other clause in this certificate of
incorporation, but the business and purposes specified in each of the foregoing
clauses of this article shall be regarded as independent business and purposes.

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     FOURTH. This corporation shall have authority to issue two classes of
capital stock, as follows:

          (a) Four Hundred Thousand (400,000) shares of Class A non-voting
     Preferred with a par value of each of such shares of 0NE ($1.00) DOLLAR,
     amounting in the aggregate to Four Hundred Thousand ($400,000) Dollars. To
     the extent available from retained earnings, each share shall receive
     semi-annually on the first day of February and the first day of August of
     each year a dividend of Six Cents ($.06) per share. All unpaid dividends
     shall be cumulative and paid as retained earnings become available. No
     dividend on Common Stock may be paid until all cumulative Preferred
     dividends are fully paid. Each Class A share shall participate equally with
     each Common share, in the receipt of dividends declared by the Corporation
     in its capital stock, in securities other than its own stock, and in
     property other than cash. The value of such dividend shall be credited
     against all cumulative unpaid dividends. For this purpose value is hereby
     defined to be fair market value to the extent it can be ascertained at the
     dividend declaration date, or, if not ascertainable, the book value thereof
     at the declaration date.

          The corporation shall not be consolidated nor merged into any other
     company nor shall all or substantially all of its property be sold as an
     entirety, without an affirmative vote of a majority of the Class A
     Preferred shares.

          Upon liquidation of the Corporation, in preference to any distribution
     on Common Stock, each share of Preferred stock shall be entitled to Two
     ($2.00) Dollars per share and all accumulated unpaid dividends. After March
     1, 1974, any share of Class A Preferred Stock is redeemable by the
     Corporation at a price of Three ($3.00) Dollars per share, upon the giving
     of not less than thirty (30) days' notice prior to the date fixed for
     redemption, registered mail, return receipt requested, provided that the
     holder of any Preferred share may convert to Common Stock at any time prior
     to the expiration of such thirty (30) days' notice.

          (b) Four Million (4,000,000) shares of Common Stock, and the par value
     of each of such shares is Ten Cents ($.10) amounting in the aggregate to
     Four Hundred Thousand ($400,000) Dollars.

     FIFTH. The corporation is to have perpetual existence.

     SIXTH. In furtherance and not in limitation of the powers conferred by
statute, the board of directors is expressly authorized:

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     To make, alter or repeal the by-laws of the corporation.

     To authorize and cause to be executed mortgages and liens upon the real and
personal property of the corporation.

     To set apart out of any of the funds of the corporation available for
dividends a reserve or reserves for any proper purpose and to abolish any such
reserve in the manner in which it was created.

     By a majority of the whole board, to designate one or more committees, each
committee to consist of two or more of the directors of the corporation. The
board may designate one or more directors as alternate members of any committee,
who may replace any absent or disqualified member at any meeting of the
committee. Any such committee, to the extent provided in the resolution or in
the by-laws of the corporation, shall have and may exercise the powers of the
board of directors in the management of the business and affairs of the
corporation, and may authorize the seal of the corporation to be affixed to all
papers which may require it; provided, however, the by-laws may provide that in
the absence or disqualification of any member of such committee or committees,
the member or members thereof present at any meeting and not disqualified from
voting, whether or not he or they constitute a quorum, may unanimously appoint
another member of the board of directors to act at the meeting in the place of
any such absent or disqualified member.

     When and as authorized by the affirmative vote of the holders of a majority
of the stock issued and outstanding having voting power given at a stockholders'
meeting duly called upon such notice as is required by statute, or when
authorized by the written consent of the holders of a majority of the voting
stock issued and outstanding, to sell, lease or exchange all or substantially
all of the property and assets of the corporation, including its good will and
its corporate franchises, upon such terms and conditions and for such
consideration, which may consist in whole or in part of money or property
including shares of stock in, and/or other securities of, any other corporation
or corporations, as its board of directors shall deem expedient and for the best
interests of the corporation.

     SEVENTH. Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof, or on the
application of any receiver or receivers appointed for this corporation under
the provisions of section 291 of Title 8 of the Delaware Code or on the
application of Trustees in dissolution or of any receiver or receivers appointed
for this corporation under the

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provisions of section 279 of Title 8 of the Delaware Code order a meeting of the
creditors or class of creditors, and/or of the stockholders or class of
stockholders of this corporation, as the case may be, to be summoned in such
manner as the said court directs. If a majority in number representing
three-fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of this corporation, as the case may be,
agree to any compromise or arrangement and to any reorganization of this
corporation as a consequence of such compromise or arrangements, the said
compromise or arrangement and the said reorganization shall, if sanctioned by
the court to which the said application has been made, be binding on all the
creditors or class of creditors, and/or on all the stockholders or class of
stockholders, of this corporation, as the case may be, and also on this
corporation.

     EIGHTH. Meetings of stockholders may be held within or without the State of
Delaware, as the by-laws may provide. The books of the corporation may be kept
(subject to any provision contained in the statues) outside the State of
Delaware at such place or places as may be designated from time to time by the
board of directors or in the by-laws of the corporation. Elections of directors
need not be by written ballot unless the by-laws of the corporation shall so
provide.

     NINTH. The corporation reserves the right to amend, alter, change or repeal
any provision contained in this certificate of incorporation, in the manner now
or hereafter prescribed by statute, and all rights conferred upon stockholders
herein are granted subject to this reservation.

     THE UNDERSIGNED, being the Vice-President of Instrument Technology
Corporation, does hereby make this certificate, hereby declaring that the
foregoing Restated Certificate of Incorporation of Instrument Technology
Corporation was duly adopted by the stockholders of Instrument Technology
Corporation in accordance with the provisions of sections 242 and 245 of Title 8
of the Delaware Code of 1953, as amended, on the 9th day of January, 1970, that
this is my act and deed and the act and deed of the corporation, that the facts
herein stated are true, and accordingly I have hereunto set my hand this 9th day
of day of January, 1970.


                                             /s/ Kenneth Foulk
                                             ---------------------------------
                                             Kenneth Foulk
                                             Vice-President
(Corporate Seal)                             Instrument Technology Corporation

ATTEST:


/s/ Lawrence Friedman
----------------------
     Secretary

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STATE OF FLORIDA   )
COUNTY OF PINELLAS ) ss:

     BE IT REMEMBERED that on this 9th day of January, 1970, personally came
before me, a Notary Public in and for the County and State aforesaid, Kenneth
Foulk, Vice-President of Instrument Technology Corporation, a corporation of the
State of Delaware, and he duly executed the foregoing Restated Certificate of
Incorporation of Instrument Technology Corporation and acknowledged the said
Restated Certificate of Incorporation to be his act and deed and the act and
deed of said corporation and the facts stated therein are true; and that the
seal affixed to said Restated Certificate of Incorporation by the Secretary of
said corporation is the common or corporate seal of said corporation.

     IN WITNESS WHEREOF I have hereunto set my hand and seal of office the day
and year aforesaid.


                                             /s/ Notary
                                             ----------------------
                                             Notary Public

(Seal)                                             (Seal)

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