Exhibit 10.70
 
PROMISSORY NOTE
 
$5,789.15
 
May 1, 2002
   
Dallas, 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        

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By:
 
/s/    HARLEY E. BARNES III        

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David M. Kirk
         
Harley E. Barnes III
CFO

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