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                                                                   Exhibit 10(b)

                             AMENDMENT NUMBER THREE
                                     TO THE
                       HARRIS CORPORATION RETIREMENT PLAN



                  WHEREAS, Harris Corporation, a Delaware corporation (the
"Corporation"), has heretofore adopted and maintains the Harris Corporation
Retirement Plan, as amended and restated effective January 1, 2003 (the "Plan");

                  WHEREAS, the Corporation, by action of the Corporation's Board
of Directors, has the authority to amend the Plan pursuant to Section 17.1 of
the Plan; and

                  WHEREAS, the Corporation, by action of the Corporation's Board
of Directors, amended the Plan at its meeting held on December 5, 2003 and
authorized and directed the President, any Vice President, the Secretary, the
Assistant Secretary, the Treasurer and any Assistant Treasurer and such other
persons as are delegated by them to execute all such instruments, documents and
certificates that such person deems necessary, advisable or appropriate.

                  NOW, THEREFORE, pursuant to such authorization and direction,
I do hereby execute the following amendment adopted by the Corporation's Board
of Directors on December 5, 2003:

         1.       Effective December 2, 2003, Section 12.1 of the Plan in
restated in its entirety to read as follows:

                  Section 12.1. Voting Shares of Harris Stock. The Trustee, or
                  the Company upon written notice to the Trustee, shall furnish
                  to each Participant (and Beneficiary) who has Harris Stock
                  credited to his or her individual account under the Harris
                  Stock Fund the date and purpose of each meeting of the
                  shareholders of the Company at which Harris Stock is entitled
                  to be voted. The Trustee, or the

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                  Company if it has furnished such information to such
                  Participants (and Beneficiaries) with respect to a particular
                  shareholders' meeting, shall request from each such
                  Participant (or Beneficiary) instructions to be furnished to
                  the Trustee (or to a tabulating agent appointed by the
                  Trustee, which may be the Company's transfer agent) regarding
                  the voting at such meeting of Harris Stock credited to the
                  Participant's (or Beneficiary's) account. If the Participant
                  (or Beneficiary) furnishes such instructions to the Trustee or
                  its agent within the time specified in the notification, then
                  the Trustee shall vote such Harris Stock in accordance with
                  such instructions. All Harris Stock credited to accounts as to
                  which the Trustee or its agent do not receive instructions as
                  specified above and all unallocated Harris Stock held in the
                  Harris Stock Fund shall be voted by the Trustee
                  proportionately in the same manner as it votes Harris Stock as
                  to which the Trustee or its agent have received voting
                  instructions as specified above.

         2.       Effective December 2, 2003, Section 12.2(a) of the Plan is
amended by adding the following sentences to the end thereof to read as follows:

                  Any securities or other property received by the Trustee as a
                  result of having tendered Harris Stock shall be held, and any
                  cash so received shall be invested, in short term investments
                  pending any further action which the Trustee may be required
                  or directed to take pursuant to the Plan. Notwithstanding
                  anything to the contrary, during the period of any public
                  offer for Harris Stock, the Trustee shall refrain from making
                  purchases of Harris Stock in connection with the Plan and the
                  Trust. In addition to compensation otherwise payable, the
                  Trustee shall be entitled to reasonable compensation and
                  reimbursement for its reasonable out-of-pocket expenses for
                  any services attributable to the duties and responsibilities
                  described in this Section.


         IN WITNESS WHEREOF, Harris Corporation has caused this instrument to be
executed on this 17th day of December 2003.


                                       HARRIS CORPORATION

                                       By: /s/ D.S. Wasserman
                                           ---------------------------
                                           David S. Wasserman
                                           Vice President - Treasurer





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