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                                                                 EXHIBIT 10.(OO)

      SECOND AMENDMENT AND WAIVER TO AMENDED AND RESTATED CREDIT AGREEMENT

            THIS SECOND AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (this
"AMENDMENT") made and entered into as of May 29, 2004 (the "EFFECTIVE DATE"), by
and among LYNCH SYSTEMS, INC., a South Dakota corporation (the "BORROWER"), and
SUNTRUST BANK, a Georgia banking corporation (the "LENDER").

                              W I T N E S S E T H:

      WHEREAS, the Borrower and the Lender are parties to a certain Amended and
Restated Credit Agreement, dated as of June 10, 2002, as amended by that certain
First Amendment to Amended and Restated Credit Agreement, dated as of May 30,
2003 (as the same may be further amended from time to time, the "CREDIT
AGREEMENT"; capitalized terms used herein and not otherwise defined herein shall
have the meanings given such terms in the Credit Agreement as amended by this
Amendment), whereby the Lender has agreed to make certain loans to the Borrower,
subject to the terms, covenants and conditions contained in the Credit
Agreement; and

      WHEREAS, the Borrower has requested that the Lender amend the Credit
Agreement as set forth in this Amendment, and the Lender is willing to agree to
such modifications subject to the terms and conditions of this Amendment.

      NOW THEREFORE, in consideration of the premises and mutual covenants
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

      1. RESERVED.

      2. AMENDMENTS TO CREDIT AGREEMENT. Subject to the terms and conditions of
this Amendment, the Credit Agreement is hereby amended as follows:

      (a) by deleting the definition of the term "Maturity Date" from Section
1.01 thereof, and by substituting, in lieu thereof, the following new definition
of such term:

            "Maturity Date" shall mean May 31, 2005, as such date may be
            extended, accelerated or amended from time to time pursuant to this
            Agreement.

      (b) by deleting the language "Two Million Dollars ($2,000,000)" from
      Section 2.01(a)(i) thereof, and by substituting, in lieu thereof, the
      following new language: "Four Million Dollars ($4,000,000)."

      3. NO OTHER WAIVERS OR AMENDMENTS; CONDITIONS SUBSEQUENT. Except for the
amendment expressly set forth and referred to in Section 2 above, the Credit
Agreement shall remain unchanged and in full force and effect. Nothing in this
Amendment is intended, or shall be construed, to constitute a novation or an
accord and satisfaction of any of the Borrower's Obligations under or in
connection with the Credit Agreement or to modify, affect or impair the

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perfection or continuity of Lender's security interests in, security titles to
or other liens on any Collateral for the Obligations.

      4. CONDITIONS TO EFFECTIVENESS. This Amendment shall become effective,
upon the Effective Date, subject to the satisfaction of the following conditions
on or prior to such date:

                  (1) the receipt by the Lender of this Amendment, duly
            executed, completed and delivered by the Lender and the Borrower;

                  (2) the receipt by the Lender of the fully-executed promissory
            note, in the form of Exhibit A attached hereto (the "NEW NOTE"), to
            replace the promissory note previously delivered under the Credit
            Agreement;

                  (3) the receipt by Lender of a non-refundable extension fee in
            the amount of $8,750 (representing 0.125% of the Non-Guaranteed Loan
            Maximum Availability), which extension fee shall be deemed fully
            earned upon the parties' execution and delivery of this Amendment;
            and

                  (4) the receipt by the Lender of such other documents,
            certificates, lien searches and instruments as the Lender may
            reasonably request.

      5. REPRESENTATIONS AND WARRANTIES. The Borrower hereby represents and
warrants to the Lender that (a) this Amendment and the New Note have been duly
authorized, executed and delivered by it, (b) no Default or Event of Default has
occurred and is continuing as of this date after giving effect to the waiver
granted in Section 1 hereof, and (c) all of the representations and warranties
made by it in the Credit Agreement are true and correct in all material respects
on and as of the date of this Amendment (except to the extent that any such
representations or warranties expressly referred to a specific prior date). Any
breach the Borrower of its representations and warranties contained in this
Section 5 shall be an Event of Default for all purposes of the Credit Agreement.

      6. RATIFICATION. The Borrower hereby ratifies and reaffirms each and every
term, covenant and condition set forth in the Credit Agreement and all other
documents delivered by the Borrower in connection therewith (including without
limitation the other Credit Documents to which the Borrower is a party),
effective as of the date hereof.

      7. ESTOPPEL. To induce the Lender to enter into this Amendment, the
Borrower hereby acknowledges and agrees that, as of the date hereof, there
exists no right of offset, defense or counterclaim in favor of the Borrower as
against the Lender with respect to the obligations of the Borrower to the Lender
under the Credit Agreement or the other Credit Documents, either with or without
giving effect to this Amendment.

      8. REIMBURSEMENT OF EXPENSES. The Borrower hereby agrees that it shall
reimburse the Lender on demand for all costs and expenses (including without
limitation reasonable attorney's fees) actually incurred by such parties in
connection with the negotiation, documentation and consummation of this
Amendment and the other documents executed in connection herewith and therewith
and the transactions contemplated hereby and thereby.

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      9. GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF GEORGIA FOR CONTRACTS TO BE PERFORMED
ENTIRELY WITHIN SAID STATE.

      10. SEVERABILITY OF PROVISIONS. Any provision of this Amendment which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof or affecting the validity or
enforceability of such provision in any other jurisdiction. To the extent
permitted by applicable law, the Borrower hereby waives any provision of law
that renders any provision hereof prohibited or unenforceable in any respect.

      11. COUNTERPARTS. This Amendment may be executed in any number of
counterparts, all of which shall be deemed to constitute but one original and
shall be binding upon all parties, their successors and permitted assigns.

      12. ENTIRE AGREEMENT. The Credit Agreement as amended by this Agreement
embodies the entire agreement between the parties hereto relating to the subject
matter hereof and supersedes all prior agreements, representations and
understandings, if any, relating to the subject matter hereof.

                  [remainder of page intentionally left blank]

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            IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed and delivered on their behalf and the Borrower has caused its
corporate seal to be hereunto affixed, all as of the date first above stated.

                                             BORROWER:
(CORPORATE SEAL)
                                             LYNCH SYSTEMS, INC.
Attest:
                                             By: /s/ A. BOWLING
                                                 -------------------------------
/s/ JANET T. GRIMSLEY                         Title: President
-----------------------------------
Title: Secretary

                                             LENDER:

                                             SUNTRUST BANK

                                             By:/S/ CATHERINE M. MATHIS
                                                --------------------------------
                                              Title: Group Vice President

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                  PARENT GUARANTOR ACKNOWLEDGMENT AND CONSENT

      The undersigned hereby acknowledges and consents to, and agree to the
terms of, the foregoing Second Amendment to Amended and Restated Credit
Agreement, and ratifies and confirms its obligations under the Parent Guaranty
(as defined in the Amended and Restated Credit Agreement).

      This 29th day of May, 2004.

LYNCH CORPORATION

By: /s/ Raymond H. Keller
    ------------------------------------
Name: Raymond H. Keller
Title: VP/CFO

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                                   EXHIBIT A

                            FORM OF PROMISSORY NOTE

                                PROMISSORY NOTE

U.S. $7,000,000                                                     MAY 29, 2004

FOR VALUE RECEIVED, the undersigned LYNCH SYSTEMS, INC., a South Dakota
corporation (the "Borrower"), hereby promises to pay to the order of SUNTRUST
BANK (herein, together with any subsequent holder hereof, called the "Lender"),
the lesser of SEVEN MILLION AND NO/100 U.S. DOLLARS (U.S. $7,000,000.00) or the
aggregate outstanding principal amount of the Loans made to the Borrower by
Lender pursuant to the terms of the Credit Agreement referred to below, which
principal sum shall be payable on the earlier of (i) the Maturity Date specified
in the Credit Agreement or (ii) the date on which all amounts outstanding under
this Promissory Note (this "Note") have become due and payable pursuant to the
provisions of Article IX of the Credit Agreement (as defined below). The
Borrower likewise promises to pay interest on the outstanding principal balance
of each Loan made by the Lender to the Borrower, at such interest rates, payable
at such times, and computed in such manner, as are specified in the Credit
Agreement in strict accordance with the terms thereof.

            This Note is issued pursuant to, and is the "Note" referred to in,
the Amended and Restated Credit Agreement dated as of June 10, 2002, between
Borrower and Lender, as amended by that certain First Amendment to Amended and
Restated Credit Agreement dated as of May 30, 2003, and as amended by that
certain Second Amendment to Amended and Restated Credit Agreement dated as the
date hereof (as the same may be further amended, modified or replaced from time
to time, the "Credit Agreement"), and the Lender is and shall be entitled to all
benefits thereof and of all the Credit Documents executed and delivered to the
Lender in connection therewith. Terms defined in the Credit Agreement are used
herein with the same meaning. The Credit Agreement, among other things, contains
provisions for acceleration of the maturity hereof upon the happening of certain
Events of Default, provisions relating to prepayments on account of principal
hereof prior to the maturity hereof, and provisions for post-default interest
rates.

            This Note is issued in replacement of and substitution for that
certain Promissory Note, dated as of May 30, 2003, issued by the Borrower in
favor of the Lender (the "PRIOR NOTE"). This Note is not intended nor shall it
be construed as a novation or an accord and satisfaction of the indebtedness
evidenced by the Prior Note.

            The Borrower agrees to make payments of principal and interest
hereon on the dates and in the amounts specified in the Credit Agreement in
strict accordance with the terms thereof.

            In case an Event of Default shall occur and be continuing, the
principal and all accrued interest of this Note may automatically become, or may
be declared, immediately due

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and payable in the manner and with the effect provided in the Credit Agreement.
The Borrower agrees to pay, and save the Lender harmless against any liability
for the payment of, all costs and expenses, including reasonable attorneys'
fees, in connection with the enforcement by the Lender of any of its rights or
remedies under this Note or the Credit Agreement.

            This Note has been delivered in Atlanta, Georgia, and the rights and
obligations of the Lender and the Borrower hereunder shall be construed in
accordance with and governed by the laws of the State of Georgia (without giving
effect to its conflicts of law rules).

            The Borrower expressly waives any presentment, demand, protest or
notice in connection with this Note, whether now or hereafter required by
applicable law. This Note is intended to be an instrument under seal.

            IN WITNESS WHEREOF, the Borrower has caused this Note to be
executed, sealed and delivered by its duly authorized officers as of the date
first above written.

(CORPORATE SEAL)                             LYNCH SYSTEMS, INC.

                                             By: /s/ A. Bowling
                                                 -------------------------------
                                             Title: President

Attest:

/s/ JANET T. GRIMSLEY
------------------------------------
Secretary

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