8-A12G/A

 
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C.  20549

                                 FORM 8-A / A

               For Registration of Certain Classes of Securities
                    Pursuant to Section 12(b) or (g) of the
                        Securities Exchange Act of 1934

                             Dynatech Corporation
             ------------------------------------------------------
             (Exact name of registrant as specified in its charter)

                                 Massachusetts
             ------------------------------------------------------
                 (State or other jurisdiction of incorporation)

             0-07438                                  04-2258582
 -------------------------------        --------------------------------------
   (Commission File Number)            (I.R.S. Employer Identification Number)

                         3 New England Executive Park
                       Burlington, Massachusetts 01803
             ------------------------------------------------------
              (Address of principal executive offices) (zip code)

      Registrant's telephone number, including area code:  (781) 272-6100


       Securities to be registered pursuant to Section 12(b) of the Act:

                                     None
             ------------------------------------------------------
                               (Title of class)

                            New York Stock Exchange
             ------------------------------------------------------
                  (Name of each exchange on which each class
                             is to be registered)

       Securities to be registered pursuant to Section 12(g) of the Act:

                                     None
             ------------------------------------------------------
                               (Title of class)

 
Item 1.  Description of Registrant's Securities to be Registered.
         ------------------------------------------------------- 

     Item 1 of the Form 8-A is hereby amended so as to read in its entirety as
follows:

     On February 16, 1989, the Board of Directors of Dynatech Corporation (the
"Company") declared a dividend distribution of one Preferred Stock Purchase
Right (a "Right") for each outstanding share of Common Stock of the Company to
stockholders of record at the close of business on March 3, 1989.  Each Right
entitles the registered holder to purchase from the Company a unit consisting of
one two-thousandth of a share (a "Unit") of Series A Junior Participating
Cumulative Preferred Stock, par value $1.00 per share (the "Preferred Stock"),
at a cash Exercise Price of $100.00 per Unit, subject to adjustment.  The
description and terms of the Rights are set forth in a Shareholder Rights
Agreement ("Rights Agreement") between the Company and the First National Bank
of Boston, as Rights Agent. The Rights Agreement was amended and restated on
March 12, 1990.  Amendment No. 1 to the Rights Agreement was executed on
December 20, 1997.

     Initially, the Rights will not be exercisable and will be attached to all
outstanding shares of Common Stock.  No separate Right Certificates will be
distributed until the Distribution Date.  The Rights will separate from the
Common Stock and the Distribution Date will occur upon the earlier of (i) 10
days following a public announcement that a person or group of affiliated or
associated persons (an "Acquiring Person") has acquired beneficial ownership of
15% or more of the outstanding shares of Common Stock (the date of said
announcement being referred to as the "Stock Acquisition Date"); provided,
however, that as a result of the execution, delivery and performance under, or
consummation of the transactions relating to and contemplated by the Agreement
and Plan of Merger (the "Merger Agreement") dated as of December 20, 1997 by and
among the Company and CDRD Merger Corporation ("Mergerco"), Mergerco shall not
be deemed an Acquiring Person for any purposes of the Shareholder Rights
Agreement, (ii) 10 business days following the commencement of a tender offer or
exchange offer that would result in a person or group owning 15% or more of the
outstanding shares of Common Stock or (iii) the determination by the Board of
Directors of the Company that a Person meets criteria specified in the Rights
Agreement and is therefore an Adverse Person; provided, however, that Mergerco
shall not, during the effectiveness of the Merger Agreement, be declared an
Adverse Person for any purpose of the Rights Agreement.

     Until the Distribution Date (or earlier redemption or expiration of the
Rights), (a) the Rights will be evidenced by the Common Stock certificates and
will be transferred with and only with such Common Stock certificates, (b) new
Common Stock certificates issued after March 3, 1989 will contain a notation
incorporating the Shareholder Rights Agreement by reference, and (c) the
surrender for transfer of any certificates for Common Stock will also constitute
the transfer of the Rights associated with the Common Stock represented by such
certificate.

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     The Rights are not exercisable until the Distribution Date and will expire
at the earlier of the Effective Time (as defined in the Merger Agreement) or the
close of business on February 16, 1999, unless previously redeemed by the
Company as described below.

     As soon as practicable after the Distribution Date, Right Certificates will
be mailed to holders of record of Common Stock as of the close of business on
the Distribution Date and, thereafter, the separate Right Certificates alone
will represent the Rights.  Except as otherwise determined by the Board of
Directors, only shares of Common Stock issued prior to the Distribution Date
will be issued with Rights.

     In the event that any Person becomes an Acquiring Person or the Board of
Directors determines that any Person is an Adverse Person, proper provision will
be made so that each holder of a Right will thereafter have the right to
receive, upon exercise thereof at the current Exercise Price, that number of
shares of Preferred Stock of the Company having a market value equal to the
result obtained by (x) multiplying the number of Units for which a right is
exercisable by the Exercise Price and then dividing the product by (y) 50% of
the fair market value of a Unit (such Right being referred to as the
"Subscription Right").  In the event that, at any time following the Stock
Acquisition Date, (i) the Company is acquired in a merger or other business
combination transaction or (ii) 50% or more of the Company's assets or earning
power is sold to any other Person or Persons, each holder of a Right shall
thereafter have the right to receive, upon exercise thereof at the current
Exercise Price, common stock of the acquiring company having a market value
equal to the result obtained by (x) multiplying the number of Units for which a
right is exercisable by the Exercise Price and then dividing the product by (y)
50% of the fair market value of a share of common stock of the acquiring company
(such Right being referred to as the "Merger Right")  In the event that a
transaction gives rise to both the Subscription Right and the Merger Right, only
the Merger Right shall be available to the holder of a Right.  Rights that are
or were beneficially owned by an Acquiring Person may (under certain
circumstances specified in the Shareholder Rights Agreement) become null and
void.

     The Exercise Price payable, and the number of Units of Preferred Stock or
other securities or property issuable, upon exercise of the Rights are subject
to adjustment from time to time to prevent dilution (i) in the event of a stock
dividend on, or a subdivision, combination or reclassification of, the Preferred
Stock, (ii) if holders of the Preferred Stock are granted certain rights,
options or warrants to subscribe for Preferred Stock or convertible securities
at less than the current market price of the Preferred Stock, or (iii) upon the
distribution to holders of the Preferred Stock of evidences of indebtedness,
cash or assets (excluding regular quarterly cash dividends) or of subscription
rights or warrants (other than those referred to above).

     With certain exceptions, no adjustment in the Exercise Price will be
required until cumulative adjustments amount to at least 1% of the Exercise
Price.  The Company is not obligated to issue fractional Units.  If the Company
elects not to issue fractional Units, in lieu 

                                      -3-

 
thereof an adjustment in cash will be made based on the fair market value of the
Preferred Stock on the last trading date prior to the date of exercise.

     Any of the provisions of the Shareholder Rights Agreement may be amended by
the Board of Directors of the Company at any time prior to the Distribution
Date.  From and after the Distribution Date, the Board of Directors of the
Company may, subject to certain limitations specified in the Shareholder Rights
Agreement, amend the Shareholder Rights Agreement to cure any ambiguity, defect
or inconsistency, to shorten or lengthen any time period under the Shareholder
Rights Agreement or to make other changes that do not adversely affect the
interests of the Rights holders (excluding the interests of Acquiring Persons or
their Affiliates or Associates).

     The Rights may be exercised in whole or in part at any time after the
Distribution Date at or prior to the earlier of (i) the earlier of the Effective
Time (as defined in the Merger Agreement) and the close of business on February
16, 1999 (the "Final Expiration Date") or (ii) the time at which the Rights are
redeemed by the Board of Directors (as described below).

     The Rights may be redeemed by the Board of Directors in whole, but not in
part, at a price of $0.02 per Right (payable in cash, Common Stock or other
consideration deemed appropriate by the Board of Directors) by the Board of
Directors until the earliest of (i) the close of business on the tenth day after
the Stock Acquisition Date, (ii) the declaration by the Board of Directors that
a Person is an Adverse Person, (iii) an event triggering the Merger Right or
(iv) the Final Expiration Date.  Immediately upon the action of the Board of
Directors ordering redemption of the Rights, the Rights will terminate and
thereafter the only right of the holders of Rights will be to receive the
redemption price.

     Until a Right is exercised, the holder will have no rights as a stockholder
of the Company (beyond those as an existing stockholder), including the right to
vote or to receive dividends.  While the distribution of the Rights will not be
taxable to stockholders or to the Company, stockholders may, depending upon the
circumstances, recognize taxable income in the event that the Rights become
exercisable for Preferred Stock (or other consideration) of the Company or for
common stock of an acquiring company as set forth above.

      The Amended and Restated Rights Agreement between the Company and the
Rights Agent, which specifies the terms of the Rights and includes as Exhibit B
the form of Right Certificate, and Amendment No. 1 to the Amended and Restated
Rights Agreement are attached hereto as Exhibits 1 and 3 and are incorporated
herein by reference. The foregoing description of the Rights does not purport to
be complete and is qualified in its entirety by reference to Exhibits 1 and 3.
 
Item 2.  Exhibits.
         -------- 

     The following exhibits are filed herewith as set forth in the Exhibit Index
of this Report (or incorporated by reference as indicated below):

                                      -4-

 
          1. Shareholder Rights Agreement dated as of February 16, 1989 as
             amended and restated as of March 12, 1990 between the Company and
             The First National Bank of Boston, as Rights Agent. (incorporated
             by reference)

          2. Form of Right Certificate. (incorporated by reference)

          3. Amendment No.1 to Shareholder Rights Agreement dated as of December
             20, 1997 between the Company and BankBoston, N.A. (formerly The
             First National Bank of Boston), as Rights Agent.

                                      -5-

 
                                   SIGNATURE

Pursuant to the requirements of Section 12 of the Securities Exchange Act of
1934, the registrant has duly caused this registration statement to be signed on
its behalf by the undersigned thereunto duly authorized.

                                    Dynatech Corporation

Dated:  May 19, 1998                By:  /s/ Allan M. Kline
                                       -------------------------------
                                       Allan M. Kline
                                       Corporate Vice President

 
                                 EXHIBIT INDEX


The following designated exhibits are filed herewith:

Exhibit
- -------

  1. Amendment No. 1 to Shareholder Rights Agreement dated as of December 20,
     1997 between the Company and BankBoston, N.A. (formerly The First National
     Bank of Boston), as Rights Agent.

EX-1

 
                                                                       EXHIBIT 1

                AMENDMENT NO. 1 TO SHAREHOLDER RIGHTS AGREEMENT
                -----------------------------------------------

          This amendment, dated as of December 20, 1997, amends the Shareholder
Rights Agreement dated as of February 16, 1989, as amended and restated as of
March 12, 1990 (the "Rights Agreement") between Dynatech Corporation (the
"Company") and BankBoston, N.A. (formerly The First National Bank of Boston), as
Rights Agent (the "Rights Agent").  Terms defined in the Rights Agreement and
not otherwise defined herein are used herein as so defined.

                              W I T N E S S E T H
                              -------------------

          WHEREAS, on February 16, 1989 the Board of Directors of the Company
authorized the issuance of Rights to purchase, on the terms and subject to the
provisions of the Rights Agreement, one share of the Company's Common Stock, par
value $.20 per share; and

          WHEREAS, on February 16, 1989, the Board of Directors of the Company
authorized and declared a dividend distribution of one Right for every share of
Common Stock of the Company outstanding on the Record Date and authorized the
issuance of one Right (subject to certain adjustments) for each share of Common
Stock of the Company issued between the Record Date and the Distribution Date;
and

          WHEREAS, on February 16, 1989, the Company and the Rights Agent
entered into the Rights Agreement, which was amended and restated on March 12,
1990 to set forth the description and terms of the Rights; and
 
          WHEREAS, pursuant to Sections 27 and 29 of the Rights Agreement, the
Company now desires to amend certain provisions of the Rights Agreement in order
to supplement certain provisions therein;

          NOW, THEREFORE, the Rights Agreement is hereby amended as follows:

          1. Section 1(a) is amended by adding the following at the end
thereof:

             "; and, provided, further, that as a result of the execution,
             delivery and performance under, or consummation of the transactions
             relating to and contemplated by the Agreement and Plan of Merger
             dated as of December 20, 1997 by and among the Company and CDRD
             Merger Corporation (the "Merger Agreement") CDRD Merger Corporation
             shall not be deemed an Acquiring Person for any purpose of this
             Agreement."

 
          2. Section 1(b) is amended by adding the following at the end thereof:

             "provided, however, that CDRD Merger Corporation shall not, during
             the effectiveness of the Merger Agreement, be declared an Adverse
             Person for any purpose of this Agreement."

          3. Section 7(a) is amended to read in its entirety as follows:

             " (a) Subject to Section 7(e) hereof, the registered holder of any
             Right Certificate may exercise the Rights evidenced thereby (except
             as otherwise provided herein) in whole or in part at any time after
             the Distribution Date upon surrender of the Right Certificate, with
             the form of election to purchase and the certificate on the reverse
             side thereof duly executed, to the Rights Agent at the office or
             offices of the Rights Agent designated for such purpose, together
             with payment of the aggregate Exercise Price for the total number
             of one two-thousandths of a share of Preferred Stock (or other
             securities, cash or other assets, as the case may be) as to which
             such surrender Rights are then exercised, at or prior to the
             earlier of (i) the earlier of the Effective Time (as defined in the
             Merger Agreement) and the close of business on February 16, 1999
             (the "Final Expiration Date") or (ii) the time at which the Rights
             are redeemed as provided in Section 23 hereof (the earlier of (i)
             or (ii) being herein referred to as the "Expiration Date"). Except
             as set forth in Section 7(e) hereof and notwithstanding any other
             provision of this Agreement, any Person who prior to the
             Distribution Date becomes a record holder of shares of Common Stock
             may exercise all of the rights of a registered holder of a Right
             Certificate with respect to the Rights associated with such shares
             of Common Stock in accordance with the provisions of this
             Agreement, as of the date such Person becomes a record holder of
             shares of Common Stock.

          4.   Except as expressly herein set forth, the remaining provisions of
the Rights Agreement shall remain in full force and effect.

          IN WITNESS WHEREOF, this Amendment No. 1 has been signed to be
effective as of the close of business on the 20th day of December, 1997 by
authorized representatives of each of the Company and the Rights Agent.

                                    DYNATECH CORPORATION


                                    By: /s/ Allan M. Kline
                                       ---------------------------------------


                                    BANKBOSTON, N.A.



                                    By:  /s/ Carol Mulny-Eori
                                       ---------------------------------------

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