Exhibit 10.70





PROMISSORY NOTE





$5,789.15

May 1, 2002Dallas, Texas





FOR VALUE RECEIVED, David M. Kirk, (Borrower), hereby
unconditionally promises to pay to the order of RF Monolithics, Inc., a Delaware corporation (Lender), in lawful money of the United States of America and in immediately available funds, the principal sum of Five Thousand, Seven
Hundred Eighty-nine Dollars and Fifteen Cents ($5,789.15) (the Loan) together with accrued and unpaid interest thereon, payable on the dates and in the manner set forth below. Note amount is the sum of unpaid balance ($3,494.78) of note
dated May 12, 1999 plus new loan amount ($2,294.37).





1.Repayment
Terms.    The principal amount of the Loan plus accrued interest shall be repaid on a monthly installment basis over a period of 36 months beginning May 2002 and ending April 2005. Amortization schedule is attached to this
document.





2.Interest Rate.    Borrower further promises to pay interest on
the outstanding principal amount hereof from the date hereof until payment in full, which interest shall be payable at the rate of Four and Seventy-Five/One Hundredths percent (4.75%) per annum or the maximum rate permissible by law (which under the
laws of the State of Texas shall be deemed to be the laws relating to permissible rates of interest on commercial loans), whichever is less. Interest shall be payable along with the principal as stated above on a 36 month installment basis.





3.Place and manor of Repayment.    All amounts payable hereunder shall be
payable at the office of Lender, unless another place of payment shall be specified in writing by Lender. Payment of principle and interest will be satisfied by a deduction from borrowers semi-monthly salary payroll.





4.Application of Payments.    Payment on this Note shall be applied first to accrued interest, and
thereafter to the outstanding principal balance thereof.





5.Secured
Note.    The full amount of this Note is secured by the Collateral identified and described below. As collateral security for prompt and complete payment and performance of all obligations of Borrower under this Note and to
induce lender to extend credit, Borrower hereby assigns, conveys, grants, pledges, and transfers to and creates in favor of Lender a security interest in all goods and personal property of Borrower whether tangible or intangible and whether now or
hereafter owned by Borrower (Collateral).





6.Default.    Each
of the following events shall be an Event of Default hereunder:




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(a)  Borrower fails to pay timely any of the principal
amount due under this Note on the date the same becomes due and payable or any accrued interest or other amounts due under this Note on the date the same becomes due and payable or within five (5) calendar days thereafter;





(b)  Borrower files any petition or action for relief under any bankruptcy, reorganization, insolvency,
or moratorium law, or any other law for the relief of, or relating to, debtors, now or hereafter in effect, or makes any assignment for the benefit of creditors, or takes any corporate action in furtherance of any of the foregoing; or





(c)  An involuntary petition is filed against Borrower (unless such petition is dismissed or
discharged within sixty (60) days), under any bankruptcy statute now or hereafter in effect, or a custodian, receiver, trustee, assignee for the benefit of creditors (or other similar official) is appointed to take possession, custody, or control of
any property of Borrower.





Upon the occurrence of an Event of Default hereunder, all unpaid principal, accrued interest and other amounts
owing hereunder shall, at the option of Lender, be immediately collectible by Lender pursuant to applicable law.





7.Waiver.    Borrower waives presentment and demand for payment, notice of dishonor, protest and notice of protest of this Note, and shall pay all costs of collection when incurred, including,
without limitation, reasonable attorneys fees, costs, and other expenses.





The right to plead any and all
statutes of limitations as a defense to any demands hereunder is hereby waived to the full extent permitted by law.





8.Governing Law.    This Note shall be governed by, and construed and enforced in accordance with, the laws of the State of Texas, excluding conflict of laws principles that would cause the
application of laws of any other jurisdiction.





9.Successors and
Assigns.    The provisions of this Note shall inure to the benefit of and be binding on any successor to Borrower and shall extend to any holder hereof.





BORROWER



RF MONOLITHICS, INC.By:

/s/    DAVID M.
KIRK



By:

/s/    HARLEY E. BARNES
IIIDavid M. Kirk





Harley E. Barnes III CFO




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