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                                                                  EXHIBIT 10.24




                                 AMENDMENT TO
                             EMPLOYMENT AGREEMENT




      This Amendment to Employment Agreement ("Amendment") is entered into as
of this 28th day of October, 1996, by and between TSX Corporation, a Nevada
corporation (the "Company"), and William H. Lambert (the "Executive").


                                 WITNESSETH:


      WHEREAS, the Executive is currently employed by the Company as Chairman,
President and Chief Executive Officer of the Company; and


      WHEREAS, the Company, ANTEC, a Delaware corporation ("ANTEC"), and TSX
Acquisition Corporation, a Nevada corporation ("Merger Sub"), have entered into
a Plan of Merger dated as of October 28, 1996 ("the Merger Agreement") pursuant
to which Merger Sub will be merged into the Company and the Company shall
continue to exist as the surviving corporation (the "Merger");and


      WHEREAS, the Company and the Executive are parties to an Employment
Agreement dated May 1, 1995 (the "Employment Agreement") which provides that in
the event the Executive's employment with the Company is terminated under
certain circumstances following a Change in Control (as defined therein) the
Company shall provide certain benefits to the Executive on terms described in
the Employment Agreement; and


       WHEREAS, the Company and the Executive desire to enter into this
Amendment to the Employment Agreement to clarify those changes in control
payments and to otherwise modify the Employment Agreement;


      NOW, THEREFORE, in consideration of the mutual covenants and promises
contined herein, and other good and valuable consideration, the receipt of
which is hereby acknowledged, the parties agree as follows:


      1.    Amendment.  The Employment Agreement is hereby amended as follows:


            (a)    Section 2 is amended in its entirety to read:


                   2.  Nature of Executive Services.  The Executive shall have
            such positions and perform such duties as the parties may mutually
            agree to facilitate the integration of the business of the Company
            with the business of ANTEC Corporation following the merger of the
            Company and TSX Acquisition Corporation (the "Merger") and to 
            further the business of the Company.


            (b)    Section 3 is amended in its entirety to read:



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                3.  Term.  The term of the Executive's employment hereunder
           shall continue for 270 days after the effective time of the Merger
           (the "Effective Time") at which time (the "Date of Termination" or
           "Termination Date") it is acknowledged that the employment of
           Executive shall have been terminated by the Company for other than
           Cause and by the Executive for Good Reason (in both cases as defined
           by Section 11 of the Agreement as it read prior to the Effective
           Time) for purposes of Section 8C of the Stock Option Agreement
           between the parties dated March 14, 1994.  The term of the Agreement
           is hereinafter referred to as the "Employment Period."  For purposes
           of clarifying Section 8C of the Stock Option Agreement, the parties
           confirm their mutual interpretation that under Section 8C, the term
           of the Option after the termination at any time of the Optionee's
           employment by the Company for other than Cause or by the Executive
           for Good Reason shall continue to be a period of ten (10) years
           following the Commencement Date (as defined in Section 5 of the
           Stock Option Agreement) as provided in Section 3 of the Stock Option
           Agreement. 



      (c)  Section 4(b) of the Employment Agreement is deleted and all
references anywhere in the Employment Agreement to Section 4(b) are deleted.


      (d)  Section 10(f) is deleted and all references anywhere in the
Employment Agreement to Section 10(f) are deleted.


      (e)  All references anywhere in the Employment Agreement to Section 11
are deleted and Section 11 is amended by deleting subsections (a), (b), (c)
(ii) and (d) and amending the first sentence of subsection (c) prior to the
beginning of paragraph (c) (i) in its entirety to read:


           (c)    It is acknowledged that upon the Effective Time, the 
      Executive's duties, titles, and offices will be changed by the amendment
      of this Agreement on October___, 1996 (the "Amendment") in a manner that
      would entitle Executive to terminate his employment under this Agreement
      for Good Reason pursuant to the provisions of this Agreement as they
      existed prior to the Amendment and obligate the Company to provide the
      benefits provided by paragraphs (i), (iii) and (iv) below.  However,
      Executive has agreed to defer the exercise of that right until the
      Termination Date, and the Company has agreed to provide the benefits
      provided by paragraphs (i), (iii) and (iv) below on the Termination Date. 
      The payment provided by paragraph (i), which will be $1,262,567 if the
      Effective Time is after January 1, 1997 as contemplated, will be paid
      with interest at the annual rate of 7.5% from the tenth date following
      the Effective Time until the date of payment.  The parties have agreed
      that these will be the Company's obligations as a result of the
      termination of the employment of the Executive.


      (f)  Section 17 shall be amended in its entirety to read:  




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      Executive shall be entitled to an office and to work out of the Company's
      offices in El Paso, Texas or Juarez, Mexico or such other location as 
      shall be mutually agreeable to Executive and the Company.


      (g)  Section 18(a) is modified by inserting the phrase "and for the
period ending two years after the Effective Time" after the phrase "the term of
this Agreement" in the second line of Section 18(a).


      (h)  Section 19(b) is deleted and Section 19(d) is amended in its
entirety to read as follows:


           (d) Costs.  If any legal action or any arbitration or other 
      proceeding is brought for the enforcement of this Agreement, or because
      of an alleged dispute, breach or default in connection with any of the
      provisions of this Agreement, the prevailing party shall be entitled to
      recover his or its reasonable attorneys' fees and other costs incurred in
      that action or proceeding, in addition to any other relief to which
      such party may be entitled.


      (i)  Schedule 1 is deleted.


      (j)  Section 18 is amended by adding the following paragraph at the end
thereof:


           (i) ANTEC Common Stock.  Following the Merger, the foregoing rights
      of the Executive with respect to the Company Shares shall apply equally
      to the common stock of ANTEC.


      2.   Conditioned on Merger.  This Amendment is conditioned upon the
consummation of the Merger.  If for any reason the Merger Agreement is
terminated, then this Amendment shall become null and void and have no force or
effect.  The parties hereto ratify and affirm their respective obligations under
the Employment Agreement, as amended by this Amendment.


      3.   Applicable Law.  The Employment Agreement and this Amendment shall
be construed and interpreted pursuant to the laws of Texas.


      4.   Entire Agreement.  The Employment Agreement and this Amendment
contain the entire agreement between the Company and the Executive and
supersedes any and all previous agreements, written or oral, between the
parties relating to the subject matter hereof.  No amendment or modification of
the terms of the Employment Agreement or this Amendment shall be binding upon
the parties hereto unless reduced to writing and signed by the Company and the
Executive.


      5.   Counterparts.  This Amendment may be executed in counterparts, each
of which shall be deemed an original.




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       6.   Severability.  In the event any provision of this Amendment is held
illegal or invalid, the remaining provisions of this Amendment shall not be
affected thereby.



      IN WITNESS WHEREOF, the Executive has hereunto set his hand, and the
Company has caused the Amendment to be executed in its name on its behalf, all
as of the day and year first above written.



                                 COMPANY:


                                 TSX CORPORATION




                                 By: /s/ William H. Lambert
                                     ------------------------
                                 Title:  COB + CEO
                                         --------------------


                                 EXECUTIVE:

                                     /s/ William H. Lambert
                                     ------------------------




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