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                                                                   Exhibit 10.33

             WAIVER AND SECOND AMENDMENT TO MASTER LEASE AGREEMENT



RF Monolithics, Inc.                                  Dated as of June 30, 2000
Sigma Road
Dallas, Texas 75244

     Re:  Master Lease Agreement dated as of November 3, 1995 (as amended, the
          "Master Lease") between RF Monolithics, Inc. ("Lessee") and Banc One
          Leasing Corporation ("Lessor")

Ladies and Gentlemen:

     Lessee has informed Lessor that each of the following events have occurred:
(a) Lessee has failed to repay by April 30, 2000 the outstanding balance of
Lessee's lease line of credit outstanding with Lessor as required by Section
                                                                     -------
4.3(b) of that certain Waiver and First Amendment to Master Lease Agreement,
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dated as of February 29, 2000 (the "Amendment Default"); (b) Lessee has failed
to comply with Section 18(e) of the Master Lease as of May 31, 2000 (the "EBITDA
               -------------
Default"), and (c) certain "Events of Default" have occurred under that certain
Letter Loan Agreement between Lessee and Bank One, Texas, National Association
(the "Loan Default"). The occurrence of the Amendment Default, the EBITDA
Default, and the Loan Default each constitutes an event of default under
paragraph 14(d) of the Master Lease (such events of default being referred to
---------------
collectively herein as the "Events of Default").

     Lessee has requested that Lessor waive the Events of Default as of May 31,
2000. This Waiver and Second Amendment to Master Lease Agreement ("Amendment")
                                                                  -----------
confirms that Lessee hereby waives the Events of Default; provided that this
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waiver is expressly limited as provided herein and all other requirements of the
Master Lease, including, without limitation, the provisions of paragraph 14(d),
                                                               ---------------
shall remain in full force and effect.

     The waiver contained in this Amendment shall be limited strictly as written
and shall not be deemed to constitute a waiver of, or any consent to
noncompliance with, any term or provision of the Master Lease except as
expressly set forth herein. Further, the waiver contained herein shall not
constitute a waiver of any future default or event of default that may occur
under the Master Lease. No delay or omission by Lessor in exercising any power,
right, or remedy shall impair such power, right, or remedy or be construed as a
waiver thereof or an acquiescence therein, and no single or partial exercise of
any such power, right, or remedy shall preclude other or further exercise
thereof or the exercise of any other power, right, or remedy under the Master
Lease or otherwise.

     Lessee and Lessor hereby agree that paragraph 2 of the Covenant Addendum to
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Master Lease Agreement is hereby amended by adding the following sentence
immediately following the last sentence thereof which shall read in its entirety
as follows:

     Notwithstanding any other provision of this Lease to the contrary, Lessee
     shall certify its compliance with each of the covenants set forth above for
     the period ending
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     August 31, 2000 by reference to the quarterly financial statements of
     Lessee prepared for such period end, such certification to be received by
     Lessor not later than October 15, 2000.

     To induce Lessor to provide the waiver and amendment contained herein,
Lessee represents and warrants that as of the date of this Amendment, there are
no claims or offsets against or defenses or counterclaims to Lessee's
obligations under the Master Lease, and Lessee waives any and all such claims,
offsets, defenses, or counterclaims whether known or unknown, arising prior to
the date hereof. Additionally, Lessee hereby releases Lessor and each of its
legal representatives, successors, affiliates, parent, subsidiaries,
predecessors, assigns, shareholders, partners, trustees, beneficiaries,
administrators, heirs, former and current officers, directors, agents,
attorneys, and employees, and its respective successors, assigns, heirs,
executors, and administrators (collectively, the "Lessor Parties") from any and
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all claims, actions, suits, causes of action, accounts, judgments, agreements,
promises, executions, debts, damages, demands, rights, obligations, liabilities,
and controversies now in existence concerning or in connection with the Master
Lease or any other agreement or document executed or delivered in connection
therewith (collectively, the "Claims") of every nature and description, in law
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or in equity, whether known or unknown, foreseen or unforseen, and regardless of
whether Lessee hereafter discovers any facts which may give rise to any Claim.


                                            BANC ONE LEASING CORPORATION


                                            By: _________________________
                                            Name: _______________________
                                            Title:_______________________


ACKNOWLEDGED AND ACCEPTED:
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RF MONOLITHICS, INC.


By:______________________________
    James Farley
    Vice President and Controller