Document:

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                                                                 EXHIBIT 10.7(a)
                             MODIFICATION AGREEMENT

         THIS MODIFICATION AGREEMENT (this "Agreement") is made as of January
19, 2000, by and between: LABARGE CLAYCO WIRELESS, L.L.C., a Missouri limited
liability company ("Borrower"); and MERCANTILE BANK NATIONAL ASSOCIATION,
formerly known as Mercantile Bank of St. Louis National Association, a national
banking association ("Bank").

                              W I T N E S S E T H:

         WHEREAS, pursuant to a certain Revolving Credit executed by Borrower
and Bank on September 1, 1997 (as modified and extended, the "Revolving
Credit"), Borrower executed a certain Promissory Note payable to Bank dated
September 1, 1997, in the original principal amount of $1,000,000.00 (as
modified and extended, the "Note");

         WHEREAS, the Revolving Credit and Note are described in and secured by
a certain Security Agreement, executed by Borrower in favor of Bank on September
1, 1997, and covering the property as more particularly described therein (the
"Security Agreement");

         WHEREAS, the Revolving Credit and Note are further described in and
guaranteed by the certain Limited Guaranty executed by LaBarge, Inc. (the
"Guarantor") in favor of Bank on September 1, 1997 (the "Guaranty"); and

         WHEREAS, Revolving Credit and Note were modified and/or extended
pursuant to a certain Extension Agreement dated as of September 1, 1997, a
certain Extension Agreement dated as of September 1, 1998, a certain
Modification Agreement dated as of January 21, 1999, a certain Extension
Agreement dated as of September 1, 1999, and a certain Extension Agreement dated
as of November 30, 1999, and Borrower desires to further modify the terms of the
Revolving Credit and Note in the manner set forth herein and Bank is willing to
agree to said modification on the terms and conditions set forth herein;

         NOW, THEREFORE, in consideration of the premises, and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, Borrower and Bank hereby agree as follows:

         1. The references to "One Million and 00/100 Dollars ($1,000,000.00)"
and "$1,000,000.00" in the Revolving Credit and the Note are deleted and
substituted with "Two Million and 00/100 Dollars ($2,000,000.00)" and
"$2,000,000.00" respectively.

         2. Borrower shall maintain an annual tangible net worth for each fiscal
year (as calculated under generally accepted accounting principles consistently
applied) of at least Six Hundred Fifty Thousand and 00/100 Dollars
($650,000.00), to be calculated as of the end of each fiscal year. The failure
of Borrower to maintain said annual tangible net worth requirement shall be an
Event of Default under the Note.

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         3. The Revolving Credit and Note, as hereby modified, are, and shall
continue to be, secured by the Security Agreement and Guaranty and any reference
to the Revolving Credit and Note in such documents shall hereafter be deemed to
include the Revolving Credit and Note as hereby modified.

         4. The Revolving Credit, Note and Security Agreement are, and shall
remain, the binding obligations of Borrower, and all of the provisions, terms,
stipulations, conditions, covenants and powers contained therein shall stand and
remain in full force and effect, except only as the same are herein and hereby
expressly and specifically varied or amended, and the same are hereby ratified
and confirmed, and Bank reserves unto itself all rights and privileges granted
thereunder.

         5. Borrower hereby reaffirms all representations, warranties, covenants
and agreements recited in the Revolving Credit, Note and Security Agreement as
of the date hereof, and the same are hereby adopted as representations,
warranties, covenants and agreements of Borrower herein. Borrower further
represents and warrants that it is not in default under any of its obligations
under the Revolving Credit, Note and Security Agreement and that it has full
power and authority to execute and deliver this Agreement, and that the
execution and delivery hereof has been duly authorized, and that all necessary
and proper acts have been performed or taken.

         6. Borrower agrees to pay all expenses incurred by Bank in connection
with this Agreement, including, but not limited to, Bank's legal fees. Said sums
are payable on demand and are secured by the Security Agreement and Guaranty.

         7. NOTICE REQUIRED BY SECTION 432.045 R.S. MO.: ORAL AGREEMENTS OR
COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO FORBEAR FROM ENFORCING REPAYMENT
OF A DEBT INCLUDING PROMISES TO EXTEND OR RENEW SUCH DEBT ARE NOT ENFORCEABLE.
TO PROTECT YOU (BORROWER(S) AND US (CREDITOR) FROM MISUNDERSTANDING OR
DISAPPOINTMENT, ANY AGREEMENTS WE REACH COVERING SUCH MATTERS ARE CONTAINED IN
THIS WRITING, WHICH IS THE COMPLETE AND EXCLUSIVE STATEMENT OF THE AGREEMENT
BETWEEN US, EXCEPT AS WE MAY LATER AGREE IN WRITING TO MODIFY IT.

                         (SIGNATURES ON FOLLOWING PAGE)

                                      -2-

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

                                      BORROWER:

                                      LABARGE CLAYCO WIRELESS, L.L.C.

                                      By:  /s/  Donald H. Nonnenkamp
                                           -------------------------
                                      Title: Manager

                                      BANK:

                                      MERCANTILE BANK NATIONAL ASSOCIATION

                                      By:  /s/  Jaycee D. Greene
                                           -------------------------
                                      Title: Assistant Vice President

                              CONSENT OF GUARANTOR

         Guarantor hereby joins in and consents to this Agreement and
acknowledges that the Revolving Credit and Note, as modified by this Agreement,
shall be and remain shall be and remain binding obligations of Borrower and of
Guarantor pursuant to the Guaranty.

                                      LABARGE, INC., GUARANTOR

                                      By:  /s/  Donald H. Nonnenkamp
                                           -------------------------
                                      Title: Vice President & CFO

                                      Date: January 19, 2000

                                      -3-<PAGE>   1

                                FOURTH AMENDMENT
                                       TO
                                 LOAN AGREEMENT
                                      AMONG
                              BANK OF AMERICA, N.A.
                                       AND
                                 LABARGE, INC.,
                               LABARGE/STC, INC.,
                             LABARGE WIRELESS, INC.
                                       AND
                                LABARGE OCS, INC.

         This AMENDMENT to LOAN AGREEMENT (the "Amendment") is entered into as
of September 30, 1999, by LABARGE, INC., LABARGE/STC, INC., LABARGE WIRELESS,
INC., AND LABARGE OCS, INC. (collectively and separately, "Borrower") and BANK
OF AMERICA. N.A. (formerly known as NationsBank, N.A., which was successor by
merger to The Boatmen's National Bank of St. Louis) ("Bank").

                                    RECITALS:

A. Borrower and Bank are parties to that certain Loan Agreement dated as of June
25, 1996, as amended by the amendment thereto dated March 20, 1997, and the
amendment thereto dated as of June 25, 1999 (as it may be amended, restated,
extended, renewed, replaced, or otherwise modified from time to time, the "Loan
Agreement").

B. Borrower has requested that Bank amend the Loan Agreement to increase
availability under the Borrower Base, which Bank is willing to do upon the terms
and conditions contained herein.

         Therefore, in consideration of the mutual agreements herein and other
sufficient consideration, the receipt of which is hereby acknowledged, Borrower
and Bank hereby amend the Loan Agreement as follows:

1.       DEFINITIONS. Capitalized terms used and not otherwise defined herein
have the meanings given them in the Loan Agreement as amended hereby.

2.       EFFECTIVE DATE OF AMENDMENT.  This Amendment shall become effective as
of September 30, 1999.

3.       AMENDMENTS TO LOAN AGREEMENT.

         3.1      REVISED  BORROWING  BASE.  Section  3.1.2 of the Loan
Agreement is hereby amended to read in its entirety as follows:

         "3.1.4.  BORROWING  BASE.  The  "Borrowing  Base" on any date for any
Revolving  Advance shall be the sum of:

                  3.1.4.1. 85% of the total outstanding principal balance of
                  Eligible Accounts as of the close of business on such date, or
                  as certified in the Borrowing Base

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                  Certificate most recently furnished to Lender as required in
                  Section 14.14, whichever is less; plus

                  3.1.4.2. An amount equal to the sum of (i) 50% of the value of
                  all Eligible Inventory that is finished goods, (ii) 30% of the
                  value of all Eligible Inventory that is raw materials or
                  work-in-process at the close of business on such date, or as
                  certified in the Borrowing Base Certificate most recently
                  furnished to Lender as required in Section 14.14, whichever is
                  less; plus

                  3.1.4.3 50% of the net book value of Borrower's equipment in
                  which Lender has a first priority Security Interest; plus

                  3.1.4.4. 75% of the net book value of Borrower's owned real
                  property (excluding its owned real property in Joplin,
                  Missouri); plus

                  3.1.4.5. $910,000 (which equals 70% of the current appraised
                  value of Borrower's owned real property in Joplin, Missouri).

         For purposes of calculating the Borrowing Base: (i) all Inventory of
         Borrower shall be valued at the lower of cost or market on a
         first-in-first-out basis; (ii) raw materials and work-in-process shall
         be deemed to be equal to total Eligible Inventory less unapplied
         progress payments and inventory reserves as regularly maintained by
         Borrower; and (iii) finished goods shall be deemed to be equal to the
         estimated cost of Borrower's unbilled jobs."

5. REPRESENTATIONS AND WARRANTIES OF BORROWER. Borrower hereby represents and
warrants to Bank as of the date hereof that (i) this Amendment has been duly
authorized by Borrower's Board of Directors, (ii) no consents are necessary from
any third parties for Borrower's execution, delivery or performance of this
Amendment, (iii) this Amendment constitutes the legal, valid and binding
obligation of Borrower enforceable against Borrower in accordance with its terms
except as the enforcement thereof may be limited by bankruptcy, insolvency or
other laws related to creditors rights generally or by the application of equity
principles, (iv) the representations and warranties in the Loan Agreement are
true and correct and have been true and correct at all times since the Effective
Date, except as described in Exhibit A hereto, and (v) there exists no Default
or Event of Default under the Loan Agreement, as amended by this Amendment.

6. EFFECT OF AMENDMENT. The execution, delivery and effectiveness of this
Amendment shall not operate as a waiver of any right, power or remedy of Bank
under the Loan Agreement or any of the other Loan Documents, nor constitute a
waiver of any provision of the Loan Agreement, any of the other Loan Documents
or any existing Default or Event of Default, nor act as a release or
subordination of the security interests of Bank under the Security Documents.
Each reference in the Loan Agreement to "the Agreement", "hereunder", "hereof",
"herein", or words of like import, shall be read as referring to the Loan
Agreement as amended by this Amendment.

7. REAFFIRMATION. Borrower hereby acknowledges and confirms that (i) except as
expressly amended hereby the Loan Agreement remains in full force and effect,
(ii) the Loan Agreement, as amended hereby, is in full force and effect, (iii)
Borrower has no defenses to its obligations under the Loan Agreement and the
other Loan Documents, and (iv) Borrower has no claim against Bank arising from
or in connection with the Loan Agreement or the other Loan Documents.

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8. GOVERNING LAW. This Amendment has been executed and delivered in St. Louis,
Missouri, and shall be governed by and construed under the laws of the State of
Missouri without giving effect to choice or conflicts of law principles
thereunder.

9. SECTION TITLES. The section titles in this Amendment are for convenience of
reference only and shall not be construed so as to modify any provisions of this
Amendment.

10. COUNTERPARTS; FACSIMILE TRANSMISSIONS. This Amendment may be executed in one
or more counterparts and on separate counterparts, each of which shall be deemed
an original, but all of which together shall constitute one and the same
instrument. Signatures to this Amendment may be given by facsimile or other
electronic transmission, and such signatures shall be fully binding on the party
sending the same.

11. NOTICE ADDRESSES. The addresses of Bank and Borrower on the signature page
hereof hereby replace the addresses for notices to Bank and Borrower,
respectively, as referred to Section 19.1 of the Loan Agreement and listed on
the signature page thereof.

12. INCORPORATION BY REFERENCE. Bank and Borrower hereby agree that all of the
terms of the Loan Documents are incorporated in and made a part of this
Amendment by this reference.

13. STATUTORY NOTICE. The following notice is given pursuant to Section 432.045
of the Missouri Revised Statutes; nothing contained in such notice will be
deemed to limit or modify the terms of the Loan Documents or this Amendment:

         ORAL AGREEMENTS OR COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO
FORBEAR FROM ENFORCING REPAYMENT OF A DEBT INCLUDING PROMISES TO EXTEND OR RENEW
SUCH DEBT ARE NOT ENFORCEABLE. TO PROTECT YOU (BORROWER) AND US (CREDITOR) FROM
MISUNDERSTANDING OR DISAPPOINTMENT, ANY AGREEMENTS WE REACH COVERING SUCH
MATTERS ARE CONTAINED IN THIS WRITING, WHICH IS THE COMPLETE AND EXCLUSIVE
STATEMENT OF THE AGREEMENT BETWEEN US, EXCEPT AS WE MAY LATER AGREE IN WRITING
TO MODIFY IT.

BORROWER AND BANK HEREBY AFFIRM THAT THERE IS NO UNWRITTEN ORAL CREDIT AGREEMENT
BETWEEN BORROWER AND BANK WITH RESPECT TO THE SUBJECT MATTER OF THIS AMENDMENT.

                            [SIGNATURE PAGE FOLLOWS]

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         IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed by appropriate duly authorized officers as of the date first above
written.

LABARGE/STC, INC.                          LABARGE WIRELESS, INC.
By its President                           By its President

/s/ Craig E. LaBarge                       /s/ Craig E. LaBarge
----------------------------               ----------------------------
Print Name: Craig E. LaBarge               Print Name: Craig E. LaBarge

Notice Address:                            Notice Address:
C/O LaBarge, Inc.                          C/O LaBarge, Inc.
9900A Clayton Road                         9900A Clayton Road
St. Louis, MO  63124                       St. Louis, MO  63124
Attn: William J. Maender                   Attn: William J. Maender
FAX # 812-9438                             FAX # 812-9438
TEL # 997-0800                             TEL # 997-0800

LABARGE, INC.                              LABARGE OCS, INC.
by its President                           by its President

/s/ Craig E. LaBarge                       /s/ Craig E. LaBarge
----------------------------               ----------------------------
Print Name: Craig E. LaBarge               Print Name: Craig E. LaBarge

Notice Address:                            Notice Address:
LaBarge, Inc.                              C/O LaBarge, Inc.
9900A Clayton Road                         9900A Clayton Road
St. Louis, MO  63124                       St. Louis, MO  63124
Attn: William J. Maender                   Attn: William J. Maender
FAX # 812-9438                             FAX # 812-9438
TEL # 997-0800                             TEL # 997-0800

BANK OF AMERICA, N.A.
By its Assistant Vice President

----------------------------
Peter J. Adams II

Notice Address:
800 Market Street
St. Louis, MO  63101
Attn: Peter J. Adams II
      M01-800-12-01
FAX # 466-7783
TEL # 466-6061

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                                    EXHIBIT A

           Additions to the Disclosure Schedule in the Loan Agreement

None if nothing listed.

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