Exhibit 10.23

Silicon Valley Bank

Amendment to Loan Documents

|Borrower: |  | Hathaway Corporation
    Hathaway Systems Corporation
    Hathaway Process Instrumentation Corporation
    Hathaway Motion Control Corporation
    Hathaway Industrial Automation, Inc.
    Computer Optical Products, Inc.
    EMOTEQ Corporation
    Motor ProductsOhio Corporation
    Motor ProductsOwosso Corporation
|--------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Date:     |  | July     , 2002                                                                                                                                                                                                                                                                                                             

THIS AMENDMENT TO LOAN DOCUMENTSis entered into between SILICON VALLEY BANK ("Silicon") and the borrower named above (jointly and
severally, "Borrower").

The
Parties agree to amend the Loan and Security Agreement between them, dated May 7, 1998 (as amended from time to time, the "Loan Agreement"), as follows, effective as of the
date hereof. (Capitalized terms used but not defined in this Amendment shall have the meanings set forth in the Loan Agreement.)

1.    Modified Credit Limit.Section 1 of the Schedule, entitled "Credit Limit", is hereby amended to read
as follows:



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2.    Modified Interest Rate.Section 2 of the Schedule to Loan and Security Agreement, entitled "2.
INTEREST," is hereby amended to read as follows:



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3.    Modified Unused Line Fee.The Unused Line Fee set forth in Section 3 of the Schedule to Loan and
Security Agreement is hereby amended to read as follows:



4.    Modified Maturity Date.Section 4 of the Schedule to Loan and Security Agreement is hereby amended to
read as follows:



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5.    Modified Financial Covenants.Section 5 of the Schedule to Loan and Security Agreement, entitled "5.
FINANCIAL COVENANTS (Section 5.1)," is hereby amended to read as follows:



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6.    Modified Covenant Regarding Banking Relationship.The covenant entitled "Banking Relationship" set forth in
Section 9 of the Schedule to Loan and Security Agreement is hereby amended to read as follows:



7.    Modified Early Termination Fee.Section 6.2 of the Loan Agreement is hereby amended in its entirety to
read as follows:



8.    Sale of Power Division a Condition Precedent.The effectiveness of this Amendment is hereby subject to the
sale of Borrower's power division assets as more fully set forth in that certain Asset Purchase Agreement by and among Qualitrol Power Products, LLC, Danaher UK Industries Limited, Hathaway Systems
Corporation, Hathaway Industrial Automation, Inc., Hathaway Process Instrumentation
Corporation, Hathaway Systems, Ltd. and Hathaway Corporation dated May 17, 2002 and consented to by Silicon pursuant to that certain Consent dated July    , 2002 (the "Power
Division Sale").

9.    Fee.In consideration for Silicon entering into this Amendment, Borrower shall concurrently pay Silicon a fee
in the amount of $21,562, which shall be non-refundable and in addition to all interest and other fees payable to Silicon under the Loan Documents. Silicon is authorized to charge said fee
to Borrower's loan account.

10.    Representations True.Borrower represents and warrants to Silicon that all representations and warranties
set forth in the Loan Agreement, as amended hereby, are true and correct.

11.    General Provisions.This Amendment, the Loan Agreement, any prior written amendments to the Loan Agreement
signed by Silicon and Borrower, and the other written documents and agreements between Silicon and Borrower set forth in full all of the representations and agreements of the parties with respect to
the subject matter hereof and supersede all prior discussions, representations, agreements and understandings between the parties with respect to the subject hereof. Except as herein expressly
amended, all of the terms and provisions of the Loan Agreement, and all

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other documents and agreements between Silicon and Borrower shall continue in full force and effect and the same are hereby ratified and confirmed.

|Borrower:                           |  | Silicon:                                    
|----------------------------------- |  | --------------------------------------------
|HATHAWAY CORPORATION                |  | SILICON VALLEY BANK                         
|By                                  |  |                                             
|                                    |  | President or Vice President                 
|By                                  |  | Secretary or Ass't Secretary                
|Borrower:                           |  | Borrower:                                   
|HATHAWAY SYSTEMS
CORPORATION        |  | HATHAWAY PROCESS
INSTRUMENTATION CORPORATION
|By                                  |  | President or Vice President                 
|By                                  |  | Secretary or Ass't Secretary                
|Borrower:                           |  | Borrower:                                   
|HATHAWAY MOTION CONTROL
CORPORATION |  | HATHAWAY INDUSTRIAL
AUTOMATION, INC.        
|By                                  |  | President or Vice President                 
|By                                  |  | Secretary or Ass't Secretary                

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|Borrower:                       |  | Borrower:                        
|------------------------------- |  | ---------------------------------
|COMPUTER OPTICAL PRODUCTS, INC. |  | EMOTEQ CORPORATION               
|By                              |  | President or Vice President      
|By                              |  | Secretary or Ass't Secretary     
|Borrower:                       |  | Borrower:                        
|MOTOR PRODUCTSOHIO CORPORATION |  | MOTOR PRODUCTSOWOSSO CORPORATION
|By                              |  | President or Vice President      
|By                              |  | Secretary or Ass't Secretary     

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GUARANTOR'S CONSENT

The undersigned acknowledges that his consent to the foregoing Agreement is not required, but the undersigned nevertheless does hereby consent to the foregoing
Agreement and to the documents and agreements referred to therein and to all future modifications and amendments thereto, and any termination thereof, and to any and all other present and future
documents and agreements between or among the foregoing parties. Nothing herein shall in any way limit any of the terms or provisions of the Continuing Guaranty of the undersigned, all of which are
hereby ratified and affirmed.

|Guarantor:                                   |  | Guarantor:                         
|-------------------------------------------- |  | -----------------------------------
|HATHAWAY CORPORATION                         |  | HATHAWAY SYSTEMS CORPORATION       
|By                                           |  | President or Vice President        
|By                                           |  | Secretary or Ass't Secretary       
|Guarantor:                                   |  | Guarantor:                         
|HATHAWAY PROCESS
INSTRUMENTATION CORPORATION |  | HATHAWAY MOTION CONTROL
CORPORATION
|By                                           |  | President or Vice President        
|By                                           |  | Secretary or Ass't Secretary       
|Guarantor:                                   |  | Guarantor:                         
|HATHAWAY INDUSTRIAL
AUTOMATION, INC.         |  | COMPUTER OPTICAL PRODUCTS, INC.    
|By                                           |  | President or Vice President        
|By                                           |  | Secretary or Ass't Secretary       

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|Guarantor:                        |  |                                 |  |   
|--------------------------------- |  | ------------------------------- |  | --
|EMOTEQ CORPORATION                |  | MOTOR PRODUCTSOHIO CORPORATION
|By                                |  | President or Vice President     |  | By
|By                                |  | Secretary or Ass't Secretary    |  | By
|Guarantor:                        |  |                                 |  |   
|MOTOR PRODUCTSOWOSSO CORPORATION |  |                                 |  |   
|By                                |  | President or Vice President     |  |   
|By                                |  | Secretary or Ass't Secretary    |  |   

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