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                                                                    EXHIBIT 3.1

                              AMENDED AND RESTATED
                            ARTICLES OF INCORPORATION
                                       OF
                           REUTER MANUFACTURING, INC.

     These Amended and Restated Articles of Incorporation supersede the Articles
of Incorporation dated June 12, 1984 and all amendments thereto.

                                   ARTICLE I.

     The name of this corporation is MagStar Technologies, Inc. (the "Company").

                                   ARTICLE II.

     The registered office of the Company in Minnesota is 410 Eleventh Avenue
South, Hopkins, Minnesota, 55343.

                                  ARTICLE III.

     The aggregate number of shares of stock which the Company shall have
authority to issue is Forty Million (40,000,000) shares, consisting of Thirty
Million (30,000,000) shares of common stock, $0.1875 par value per share (the
"Common Stock"), and Ten Million (10,000,000) shares of preferred stock, $0.1875
par value per share (the "Preferred Stock"). The Board of Directors is
authorized to establish, from the authorized and undesignated shares of
Preferred Stock, one or more classes or series of shares, to designate each such
class and series, and to fix the rights and preferences of each such class and
series. Without limiting the authority of the Board of Directors granted hereby,
each such class or series of Preferred Stock shall have such voting powers (full
or limited or no voting powers), such preferences and relative, participating,
optional or other special rights, and such qualifications, limitations or
restrictions as shall be stated and expressed in the resolution or resolutions
providing for the issue of such class or series of Preferred Stock as may be
adopted from time to time by the Board of Directors prior to the issuance of any
shares thereof. Except as provided in the resolution or resolutions of the Board
of Directors creating any series of Preferred Stock, the shares of Common Stock
shall have the exclusive right to vote for the election and removal of directors
and for all other purposes. Each holder of Common Stock shall be entitled to one
vote for each share held.

     Of the Ten Million shares of Preferred Stock, Two Million Five Hundred
Thousand (2,500,000) shares shall be designated Series A convertible preferred
stock, $0.1875 par value per share (the "Series A Preferred") and Seven Million
Five Hundred Thousand (7,500,000) shares shall be undesignated as to series.

     The relative rights, preferences and privileges of the Series A Preferred
shall be as follows:


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I.   VOTING RIGHTS.

     A.   GENERAL. At all meetings of the shareholders of the Company and in the
          case of any actions of shareholders in lieu of a meeting, each holder
          of Series A Preferred shall have that number of votes on all matters
          submitted to the shareholders that is equal to the number of whole
          shares of Common Stock into which such holder's shares of Series A
          Preferred are then convertible, as provided in Section IV, at the
          record date for the determination of the shareholders entitled to vote
          on such matters or, if no such record date is established, at the date
          such vote is taken or any written consent of such shareholders is
          effected. This provision for determination of the number of votes to
          which each holder of the Series A Preferred is entitled shall also
          apply in cases in which the holders of the Series A Preferred have the
          right to vote together as a separate class. Except as may be otherwise
          provided in this Certificate or by agreement, the holders of the
          Common Stock and the holders of the Series A Preferred shall vote
          together as a single class on all actions to be taken by the
          shareholders of the Company.

     B.   QUORUMS. The presence in person or by proxy of the holders of a
          majority of the aggregate number of shares of Common Stock and Series
          A Preferred then outstanding (on an as-if converted to Common Stock
          basis) shall constitute a quorum of the Common Stock and Series A
          Preferred.

II.  DIVIDENDS.

     A.   DIVIDENDS. The holders of Series A Preferred then outstanding shall be
          entitled to receive cumulative cash dividends, out of any funds and
          assets of the Company legally available therefor, prior and in
          preference to any declaration or payment of any dividend (other than a
          Common Stock Dividend) payable on Common Stock of the Company at the
          annual rate of nine percent (9%) for the Series A Preferred, and such
          dividends shall be payable only if, as and when declared by the Board
          of Directors of the Company (the "Board"). Other than as set forth in
          the preceding sentence, no dividend or other distribution shall accrue
          or be paid with respect to any shares of capital stock of the Company
          for any period, whether before or after the effective date of this
          Certificate, unless and until declared by the Board. In the event any
          dividend or distribution is declared or made with respect to
          outstanding shares of Common Stock, a comparable dividend or
          distribution shall be simultaneously declared or made with respect to
          the outstanding shares of Series A Preferred (as if fully converted
          into Common Stock, including fractions of shares). Dividends on shares
          of capital stock of the Company shall be payable only out of funds
          legally available therefor.

     B.   NON-CASH DIVIDENDS. Whenever a dividend provided for in this Section
          II shall be payable in property other than cash, the value of such
          dividend shall be deemed to be the fair market value of such property
          as determined in good faith by the Board.


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III. LIQUIDATION RIGHTS.

     A.   NO PREFERENCE OF SERIES A PREFERRED. In the event of any liquidation,
          dissolution or winding up of the Company, whether voluntary or
          involuntary, the assets of the Company available for distribution to
          its shareholders, whether such assets are capital, surplus, or
          earnings, shall be distributed equally, on a per share basis, among
          the holders of the Common Stock and the Series A Preferred (on an
          as-if converted to Common Stock basis).

     B.   REORGANIZATION; SALE OF ASSETS. The merger, acquisition or
          consolidation of the Company into or with any other entity or entities
          which results in the exchange of outstanding shares of the Company for
          securities or other consideration issued or paid or caused to be
          issued or paid by any such entity or affiliate thereof pursuant to
          which the shareholders of the Company immediately prior to the
          transaction do not own a majority of the outstanding shares of the
          surviving corporation immediately after the transaction, or any sale,
          lease, license (on an exclusive basis) or transfer by the Company of
          all or substantially all its assets, shall be deemed to be a
          liquidation, dissolution or winding up of the Company within the
          meaning of the provisions of this Section III.

     C.   DETERMINATION OF CONSIDERATION. To the extent any distribution
          pursuant to Section III(A) consists of property other than cash, the
          value thereof shall, for purposes of Section III(A), be the fair value
          at the time of such distributions as determined in good faith by the
          Board.

IV.  CONVERSION.  The holders of the Series A Preferred shall have the following
     conversion rights (the  "Conversion Rights"):

     A.   OPTIONAL CONVERSION OF THE SERIES A PREFERRED. The Series A Preferred
          shall be convertible, without the payment of any additional
          consideration by the holder thereof and at the option of the holder
          thereof, at any time after the first issuance of shares of Series A
          Preferred by the Company, at the office of the Corporation or any
          transfer agent for the Common Stock, into such number of fully paid
          and nonassessable shares of Common Stock as is determined by dividing
          $0.1777778 by the Conversion Price, determined as hereinafter
          provided, in effect at the time of conversion and then multiplying
          such quotient by each share of Series A Preferred to be converted. The
          Conversion Price at which shares of Common Stock shall be deliverable
          upon conversion without the payment of any additional consideration by
          the holder thereof (the "Conversion Price") shall at the time of the
          filing of this Certificate initially be $0.1777778 in the case of the
          Series A Preferred. Such initial Conversion Price shall be subject to
          adjustment, in order to adjust the number of shares of Common Stock
          into which the Series A Preferred is convertible, as hereinafter
          provided.


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     B.   FRACTIONAL SHARES. No fractional shares of Common Stock shall be
          issued upon conversion of the Series A Preferred. In lieu of any
          fractional share to which any holder would otherwise be entitled upon
          conversion of the Series A Preferred owned by such holder, the Company
          shall pay cash equal to such fraction multiplied by the then effective
          Conversion Price or round up to the nearest whole share.

     C.   MECHANICS OF OPTIONAL CONVERSION. Before any holder of Series A
          Preferred shall be entitled to convert the same into full shares of
          Common Stock, such holder shall surrender the certificate or
          certificates therefor, endorsed or accompanied by written instrument
          or instruments of transfer, in form satisfactory to the Company, duly
          executed by the registered holder or by such holder's attorney duly
          authorized in writing, at the office of the Company or of any transfer
          agent for the Common Stock, and shall give written notice to the
          Company at such office that such holder elects to convert the same and
          shall state therein such holder's name or the name of the nominees in
          which such holder wishes the certificate or certificates for shares of
          Common Stock to be issued. The Company shall, as soon as practicable
          thereafter, issue and deliver at such office to such holder of Series
          A Preferred, or to such holder's nominee or nominees, a certificate or
          certificates for the number of shares of Common Stock to which such
          holder shall be entitled as aforesaid, together with cash in lieu of
          any fraction of a share. Such conversion shall be deemed to have been
          made immediately prior to the close of business on the date of such
          surrender of the shares of Series A Preferred to be converted, and the
          person or persons entitled to receive the shares of Common Stock
          issuable upon conversion shall be treated for all purposes as the
          record holder or holders of such shares of Common Stock on such date.
          From and after such date, all rights of the holder with respect to the
          Series A Preferred so converted shall terminate, except only the right
          of such holder, upon the surrender of his, her or its certificate or
          certificates therefor, to receive certificates for the number of
          shares of Common Stock issuable upon conversion thereof and cash for
          fractional shares.

D.   CERTAIN ADJUSTMENTS TO CONVERSION PRICE FOR STOCK SPLITS, DIVIDENDS,
     MERGERS, REORGANIZATIONS, ETC.


          1.   ADJUSTMENT FOR STOCK SPLITS, STOCK DIVIDENDS AND COMBINATIONS OF
               COMMON STOCK. In the event the outstanding shares of Common Stock
               shall, after the filing of this Certificate be further subdivided
               (split), or combined (reverse split), by reclassification or
               otherwise, or in the event of any dividend or other distribution
               payable on the Common Stock in shares of Common Stock, the
               applicable Conversion Price in effect immediately prior to such
               subdivision, combination, dividend or other distribution shall,
               concurrently with the effectiveness of such subdivision,
               combination, dividend or other distribution, be proportionately
               adjusted.


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          2.   ADJUSTMENT FOR MERGER OR REORGANIZATION, ETC. In the event of a
               reclassification, reorganization or exchange (other than
               described in subsection IV(D)(1) above) or any consolidation or
               merger of the Company with another corporation (other than a
               merger, acquisition or other reorganization as defined in Section
               III(B), which shall be considered a liquidation pursuant to
               Section III above), each share of Series A Preferred shall
               thereafter be convertible into the number of shares of stock or
               other securities or property to which a holder of the number of
               shares of Common Stock of the Company deliverable upon conversion
               of the Series A Preferred would have been entitled upon such
               reclassification, reorganization, exchange, consolidation, merger
               or conveyance had the conversion occurred immediately prior to
               the event; and, in any such case, appropriate adjustment (as
               determined by the Board) shall be made in the application of the
               provisions herein set forth with respect to the rights and
               interests thereafter of the holders of the Series A Preferred, to
               the end that the provisions set forth herein (including
               provisions with respect to changes in and other adjustments of
               the applicable Conversion Price) shall thereafter be applicable,
               as nearly as reasonably may be, in relation to any shares of
               stock or other property thereafter deliverable upon the
               conversion of the Series A Preferred.

          3.   ADJUSTMENTS FOR OTHER DIVIDENDS AND DISTRIBUTIONS. In the event
               the Company, at any time or from time to time after the filing of
               this Certificate, makes, or fixes a record date for the
               determination of holders of Common Stock entitled to receive, a
               dividend or other distribution payable in securities of the
               Company other than shares of Common Stock, then and in each such
               event, provision shall be made so that the holders of Series A
               Preferred shall receive upon conversion thereof, in addition to
               the number of shares of Common Stock receivable thereupon, the
               amount of securities of the Company which they would have
               received had their Series A Preferred been converted into Common
               Stock on the date of such event and had they thereafter, during
               the period from the date of such event to and including the
               conversion date, retained such securities receivable by them as
               aforesaid during such period, subject to all other adjustments
               called for during such period under this Section IV(D) with
               respect to the rights or the holders of the Series A Preferred.

     E.   NOTICES OF RECORD DATE. In the event of any taking by the Company of a
          record of the holders of any class of securities for the purpose of
          determining the holders thereof who are entitled to receive any
          dividend (other than a cash dividend which is the same as cash
          dividends paid in previous quarters) or other distribution, any
          capital reorganization of the Company, any reclassification or
          recapitalization of the Company's capital stock, any consolidation or
          merger with or into another Company, any transfer of all or
          substantially all of the assets of the Company or any dissolution,
          liquidation or winding up of the Company, the Company shall mail to
          each holder of Series A Preferred at least ten (10) days prior to the
          date


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          specified for the taking of a record, a notice specifying the
          date on which any such record is to be taken for the purpose of such
          dividend or distribution.

                                   ARTICLE IV.

     No shareholder of this Company shall have any cumulative voting rights.

                                   ARTICLE V.

     No shareholder of this Company shall have any preemptive rights by virtue
of Section 302A.413 of the Minnesota Statutes (or similar provisions of future
law) to subscribe for, purchase or acquire any shares of the Company of any
class, whether unissued or now or hereafter authorized, or any obligations or
other securities convertible into or exchangeable for any such shares.

                                   ARTICLE VI.

     Any action required or permitted to be taken at a meeting of the Board of
Directors of this Company may be taken by written action signed by the number of
directors that would be required to take such action at a meeting of the Board
of Directors at which all directors are present.

                                  ARTICLE VII.

     No director of this Company shall be personally liable to the Company or
its shareholders for monetary damages for breach of fiduciary duty by such
director as a director; provided, however, that this Article VII shall not
eliminate or limit the liability of a director to the extent provided by
applicable law (i) for any breach of the director's duty of loyalty to the
Company or its shareholders, (ii) for acts or omissions not in good faith or
that involve intentional misconduct or a knowing violation of law, (iii) under
Section 302A.559 or Section 80A.23 of the Minnesota Statutes, as amended, (iv)
for any transaction from which the director derived an improper personal
benefit, or (v) for any act or omission occurring prior to the effective date of
this Article VII. If the Section 302A of the Minnesota Statutes is hereinafter
amended to authorize the further elimination or limitation of the liability of
directors, then the liability of a director of the Company in addition to the
limitation and elimination of personal liability provided herein, shall be
eliminated or limited to the fullest extent permitted by the Minnesota Statutes,
as so amended. No amendment to or repeal of this Article VII shall apply to, or
have any effect on, the liability or alleged liability of any director for or
with respect to any acts or omissions of such director occurring prior to such
amendment or repeal.

                                  ARTICLE VIII.

     The Company shall indemnify its officers and directors to the fullest
extent permissible under the provisions of Chapter 302A of the Minnesota
Statutes, as amended from time to time, or as required or permitted by other
provisions of law. Any repeal or modification of this Article VIII will be
prospective only and will not adversely affect any right to indemnification of a
director or officer of the Company existing at the time of such repeal or
modification.

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     IN WITNESS WHEREOF, the Company has caused these Amended and Restated
Articles of Incorporation to be signed by Michael J. Tate, its President, this
31st day of May, 2001.


REUTER MANUFACTURING, INC.

By:  /s/ MICHAEL J. TATE
     -----------------------------------------
     Michael J. Tate
Its: President