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                                                                   EXHIBIT 10.20

                          SECOND AMENDED LOAN AGREEMENT

     WHEREAS, on the 25th day of October, 2000, STILLWATER NATIONAL BANK AND
TRUST COMPANY OF STILLWATER, OKLAHOMA (hereinafter referred to as the "Bank")
and WESTWOOD CORPORATION, a Nevada Corporation (hereinafter referred to as
"Westwood"), TANO CORP., a Louisiana Corporation (hereinafter referred to as
"TANO"), NMP CORP., an Oklahoma Corporation (hereinafter referred to as "NMP"),
and MC II ELECTRIC COMPANY, a Texas Corporation (hereinafter referred to as
"MCII"), (collectively Westwood, Tano, NMP and MCII are hereinafter referred to
as "Debtor") entered into a Loan Agreement (hereinafter referred to as the "Loan
Agreement"), wherein the Bank agreed to enter into a revolving loan agreement
whereby the Bank would loan to the Company up to TWO MILLION EIGHT HUNDRED
THOUSAND and NO/100 DOLLARS ($2,800,000.00) for the purpose of financing the
Company's ongoing operations, which agreement was evidenced by a Renewal and
Amended Revolving Promissory Note of even date therewith ("Note"); and

     WHEREAS, on June 25, 2001, Bank and Debtor entered into an Amended Loan
Agreement whereby the parties amended the Loan Agreement by, among other things,
extending the Maturity Date and increasing the rate of interest contained in the
Note.

     WHEREAS, the parties wish to make further adjustments to the lending
arrangements between the parties, including increasing the line of credit
available to the Debtor to THREE MILLION EIGHT HUNDRED THOUSAND and NO/100
DOLLARS ($3,800,000.00), extending the Maturity Date in the Note and adjusting
the interest rate charged in the Note.

     NOW, THEREFORE, in consideration of the mutual promises herein contained,
the parties hereby agree to amend the Loan Agreement in the following respects:

     1.   Paragraphs 1.1, 1.1 (a) and 1.1 (b) of the Loan Agreement are amended
to read as follows:

          1.1  Subject to the terms and conditions of this Agreement, Debtor
          shall have the right from time to time, prior to the "Termination
          Date" (defined below), to borrow and, upon repayment, reborrow from
          the Bank amounts not at any one time in the aggregate principal
          balance exceeding the lesser of: (i) the Borrowing Base determined as
          of the date of borrowing; or (ii) Three Million Eight Hundred Thousand
          and No/100 Dollars ($3,800,000.00) (hereinafter referred to as
          "Revolving Loan"). For these purposes:

               (a) "Termination Date" means July 15, 2002.

               (b) "Borrowing Base" means, as of any given date, the sum of the
               following factors: (1) seventy-five percent (75%), or at the
               Bank's sole discretion any lesser percentage designated upon
               forty-five (45) days notice, of Eligible Trade Accounts
               Receivable of TANO, MC II and NMP; plus (2) fifty percent (50%)
               of the value of the inventory of TANO, MCII, and NMP, not to
               exceed Two Million and No/100 Dollars ($2,000,000.00).

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     2.   Paragraph 1.1(c)(7) of the Loan Agreement is amended to read as
follows:

          (7) Eligible Trade Accounts Receivable shall not include any account
          receivable of the same account debtor to any of the Debtors in excess
          of fifteen percent (15%) of the then Eligible Trade Accounts
          Receivable calculated after excluding this debtor's Eligible Trade
          Accounts Receivable, provided, however Eligible Trade Accounts
          Receivable may include the following: accounts receivable of CECOM and
          Ingalls up to a maximum of forty percent (40%) of the then Eligible
          Trade Account after excluding CECOM and Ingalls Eligible Trade
          Accounts Receivable; accounts receivable of DFAS up to a maximum of
          twenty-five percent (25%) of the then Eligible Trade Account after
          excluding DFAS Eligible Trade Accounts Receivable; the accounts
          receivable of Avondale up to a maximum of twenty-five percent (25%) of
          the then Eligible Trade Account after excluding Avondale Eligible
          Trade Accounts Receivable, and accounts receivable of Bath Ironworks
          up to a maximum of twenty-five percent (25%) of the then Eligible
          Trade Account after excluding Bath Ironworks Eligible Trade Accounts
          Receivable; and

     3.   Paragraph 1.2 of the Loan Agreement shall be amended to reflect that
the "Renewal Note" which is defined in that paragraph refers to the Second
Amended and Restated Promissory Note between the parties dated of even date
hereof in the original principal amount of Three Million Eight Hundred Thousand
and NO/100 Dollars ($3,800,000.00).

     4.   Paragraph 2 of the Loan Agreement is amended to read as follows:

          2.1 The interest rate on the Renewal Note shall be the greater of the
          "Minimum Interest Rate" (defined below) and the "Adjusted Interest
          Rate" (defined below) which is subject to change from time to time
          based on changes in the "Index" (defined below). The Adjusted Interest
          Rate shall be a rate per annum equal to the sum of the "Base Rate"
          (defined below) and the "Margin" (defined below). The Contract Rate
          shall fluctuate during the term of this Note based upon the sum of the
          Base Rate and the Margin.

          2.2 The Base Rate may be adjusted up or down DAILY, and shall equal
          the lowest base rate on corporate loans posted by at least
          seventy-five percent (75%) of the nation's 30 largest banks as
          published in the money rates section of the Southwest Edition of the
          Wall Street Journal. Bank will inform Debtor what the current Base
          Rate is at any time during the term of the Renewal Note upon request
          of Debtor. The Base Rate will not change more often than once each
          DAY.

          2.3 The Margin shall be one and one-half (11/2) percentage points.

          2.4 The Minimum Interest Rate shall equal six and one half percent (6
          1/2%).

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     5. This Loan Agreement shall be further amended to provide that upon the
execution of this Second Amended Loan Agreement, and as a condition precedent
thereto, the Debtor shall pay to the Bank a Loan Fee of Two Thousand Five
Hundred and No/100 Dollars ($2,500.00).

     6. Except as may be amended herein, the terms and conditions of the Loan
Agreement remain in full force and effect.

     IN WITNESS WHEREOF, this Agreement is executed this 18th day of December,
2001.

                                    "BANK"
                                    STILLWATER NATIONAL BANK AND TRUST
                                    COMPANY, STILLWATER, OKLAHOMA


                                    By:      /s/ Joe E. Staires
                                        ----------------------------------------
                                        Joe E. Staires, Senior Vice President

                                    "COMPANY"
                                    Westwood Corporation, a Nevada corporation

                                    By:      /s/ Ernest H. McKee
                                        ----------------------------------------
                                        Ernest H. McKee, President

                                    TANO Corp., a Louisiana corporation

                                    By:      /s/ Guy Hardwick
                                        ----------------------------------------
                                        Guy Hardwick, President

                                    NMP Corp., an Oklahoma corporation

                                    By:      /s/ Ernest H. McKee
                                        ----------------------------------------
                                        Ernest H. McKee, President

                                    MC II Electric Company, a Texas corporation


                                    By:      /s/ Ernest H. McKee
                                        ----------------------------------------
                                        Ernest H. McKee, President

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