Exhibit
10.4

    


    NOTE
MODIFICATION

     

    THIS NOTE
MODIFICATION dated as of February 19, 2010, is executed by AEROSONIC CORPORATION
(the “Company”), a Delaware corporation, OP TECHNOLOGIES, INC., an Oregon
corporation, and AVIONICS SPECIALTIES, INC., a Virginia corporation,
(collectively, “Borrowers”) for  the benefit of Redmond Family
Investments, LLLP (“Redmond”).

     

    RECITALS

     

    WHEREAS,
the Company and Redmond are parties to a Loan Agreement dated as of May 14, 2009
(the “Loan Agreement”) as evidenced by a note dated May 14, 2009 executed and
delivered by the Borrowers to Redmond (the “Note”); and

     

    WHEREAS,
the Company has requested that Redmond agree to amend and waive certain
provisions of the Loan Agreement and Redmond is agreeable to such request but
only upon the terms and subject to the conditions set forth herein.

     

    WHEREAS,
the Company and Redmond shall enter into a First Amendment to Loan Agreement
dated as of February 19, 2010 (the “Loan Amendment”).

     

    WHEREAS,
in connection with the Loan Amendment, the Borrowers shall amend and modify the
Note as follows:

     

    


    1.           Amendments

    


    (a)  Section
2 of the Note is hereby amended and modified by deleting therefrom the
definition of “Maturity
Date” in its entirety and inserting the following new
definition:

    


    “’Maturity
Date’ means the earlier of:  (i) April 10, 2011, or (ii) the maturity
of the Existing Loans.”  

    


    (b)  Section
3 of the Note is hereby amended and modified by deleting therefrom the words
“April 10, 2010” and replacing with the words “April 10, 2011”.

    


    2.           The
State of Florida documentary excise tax in the amount of $1750.00 has previously
been paid directly to the Florida Department of Revenue.

     

    3.           All
references in the Note to “Loan Agreement” shall refer to the Loan Agreement as
amended by the Loan Amendment.

     

    4.           Notwithstanding
the execution of this Note Modification, the Note shall remain in full force and
effect, as modified hereby; and nothing herein contained and nothing done
pursuant hereto shall be construed to release, satisfy, discharge, terminate or
otherwise affect or impair in any manner whatsoever the validity or
enforceability of the indebtedness evidenced by the Note, except as expressly
modified hereby.

     

    5.           The
validity, construction, interpretation, and enforcement of this Note
Modification are governed by the laws of the State of Florida and the federal
laws of the United States of America, excluding the laws of those jurisdictions
relating to the resolution of conflicts with laws of other
jurisdictions.  

    


    [Signature
pages follow]


    
      
         


      

      
         


        
          

        

      

      
         


      

    

    


    EXECUTED:  February
19, 2010

    
      


      
        
          
            	 
      	 
      	
                    AEROSONIC
      CORPORATION

                  
	 
      	 
      	
                    AVIONICS
      SPECIALTIES, INC.

                  
	 
      	 
      	
                    OP
      TECHNOLOGIES, INC.

                  
	 
      	 
      	 
      
	
                    WITNESSES:

                  	 
      	
                    By:

                  	
                    /s/
      Douglas J. Hillman

                  
	 
      	 
      	 
      	
                    Douglas
      J. Hillman

                  
	 
      	 
      	 
      	
                    President
      and Chief Executive
Officer

                  


          

        

      

      


      
        
          
            
              
                
                  
                    	
                              

                          	 
      	 
      
	
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