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                                                                    EXHIBIT 10.5




                                  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
contained 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 28, 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: Chairman, President and
                                                 Chief Executive Officer
                                                 -----------------------



                                                 EXECUTIVE:


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





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