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                                                                   EXHIBIT 10.26

                               SIXTH AMENDMENT TO
                           LOAN AND SECURITY AGREEMENT
                        AND CERTAIN OTHER LOAN DOCUMENTS

     THIS SIXTH AMENDMENT TO LOAN AND SECURITY AGREEMENT AND CERTAIN OTHER LOAN
DOCUMENTS (the "Amendment") is made and entered into as of the 28th day of
August, 1997, to be effective (unless otherwise specified herein) as of August
28, 1997 (the "Effective Date"), by and among FLEET CAPITAL CORPORATION, a Rhode
Island corporation, successor in interest by merger to FLEET CAPITAL
CORPORATION, a Connecticut corporation, formerly known as SHAWMUT CAPITAL
CORPORATION, successor in interest by assignment to BARCLAYS BUSINESS CREDIT,
INC. ("Lender"), LOWRANCE ELECTRONICS, INC., a Delaware corporation
("Lowrance"), LEI EXTRAS, INC., a Delaware corporation ("LEI"), LOWRANCE
CONTRACTS, INC., a Delaware corporation ("Lowrance Contracts"), and SEA
ELECTRONICS, INC., an Oklahoma corporation ("Sea Electronics") (Lowrance, LEI,
Lowrance Contracts and Sea Electronics are herein individually and collectively
called "Borrower").

                                   RECITALS

     A. Borrower, Lowrance Australia Pty Limited ("Lowrance Australia") and
Lender have entered into that certain Loan and Security Agreement, dated
December 15, 1993, as amended by (i) that certain First Amendment to Loan and
Security Agreement, dated October 16, 1995, by and among Lender, Borrower and
Lowrance Australia, (ii) that certain Second Amendment to Loan and Security
Agreement, dated November 1, 1996 by and among Lender and Borrower, (iii) that
certain Third Amendment to Loan and Security Agreement, dated December 30, 1996,
by and among Lender and Borrower, (iv) that certain Fourth Amendment to Loan and
Security Agreement, entered into effective as of April 1, 1997, by and among
Lender and Borrower, and (v) that certain Fifth Amendment to Loan and Security
Agreement, entered into effective as of August 25, 1997, by and between Lender
and Borrower (as amended, the "Loan Agreement").

     B. Borrower and Lender desire to amend the Loan Agreement and certain of
the other Loan Documents as hereinafter set forth.

     NOW, THEREFORE, in consideration of the premises herein contained and other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties, intending to be legally bound, agree as follows:

                                    ARTICLE I
                                   Definitions

     1.01 Capitalized terms used in this Amendment are defined in the Loan
Agreement, as amended hereby, unless otherwise stated.

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                                   ARTICLE II
                                   Amendments

     2.01 Addition of New Section 12.21(A) to the Loan Agreement. Effective as
of the Effective Date, a new Section 12.21(A), Further Security Interest in
Australian Property is hereby added to of the Loan Agreement to read in its
entirety as follows:

               "12.21A. Further Security Interest in Australian Property.
               Notwithstanding any other provision of this Agreement, nothing
               contained herein shall create a security interest in, or
               constitute an assignment of, any Property of the Borrower which
               is located in the Australian states of Queensland, Western
               Australia, South Australia and Tasmania."

                                   ARTICLE III
                              Conditions Precedent

     3.01 Conditions Precedent. The effectiveness of this Amendment is subject
to the satisfaction of the following conditions precedent, unless specifically
waived in writing by Lender:

           (a) Lender shall have received each of the following, each in form
and substance satisfactory to Lender: (i) this Amendment, duly executed by
Borrower; and (ii) such additional documents, instruments and information as
Lender or its legal counsel may request;

           (b) The representations and warranties contained herein, in the Loan
Agreement and in the other Loan Documents, as each is amended hereby, shall be
true and correct as of the date hereof, as if made on the date hereof;

           (c) After giving effect to this Amendment, no Default or Event of
Default shall have occurred and be continuing, unless such Default or Event of
Default has been specifically waived in writing by Lender; and

           (d) All corporate proceedings taken in connection with the
transactions contemplated by this Amendment and all documents, instruments and
other legal matters incident thereto shall be satisfactory to Lender and its
legal counsel.

                                   ARTICLE IV
                                    No Waiver

     Nothing contained in this Amendment shall be construed as a waiver by
Lender of any covenant or provision of the Loan Agreement, the other Loan
Documents, this Amendment, or of

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any other contract or instrument between Borrower and Lender, and the failure of
Lender at any time or times hereafter to require strict performance by Borrower
of any provision thereof shall not waive, affect or diminish any right of Lender
to thereafter demand strict compliance therewith. Lender hereby reserves all
rights granted under the Loan Agreement, the other Loan Documents, this
Amendment and any other contract or instrument between Borrower and Lender.

                                    ARTICLE V
                  Ratifications, Representations and Warranties

     5.01 Ratifications. The terms and provisions set forth in this Amendment
shall modify and supersede all inconsistent terms and provisions set forth in
the Loan Agreement and the other Loan Documents, and, except as expressly
modified and superseded by this Amendment, the terms and provisions of the Loan
Agreement and the other Loan Documents are ratified and confirmed and shall
continue in full force and effect. Borrower and Lender agree that the Loan
Agreement and the other Loan Documents, as amended hereby, shall continue to be
legal, valid, binding and enforceable in accordance with their respective terms.

     5.02 Representations and Warranties. Borrower hereby represents and
warrants to Lender that (a) the execution, delivery and performance of this
Amendment and any and all other Loan Documents executed and/or delivered in
connection herewith have been authorized by all requisite corporate action on
the part of Borrower and will not violate the Certificate of Incorporation or
Bylaws of Borrower; (b) the representations and warranties contained in the Loan
Agreement, as amended hereby, and any other Loan Documents are true and correct
on and as of the date hereof and on and as of the date of execution hereof as
though made on and as of each such date; (c) no Default or Event of Default
under the Loan Agreement, as amended hereby, has occurred and is continuing; (d)
Borrower is in full compliance with all covenants and agreements contained in
the Loan Agreement and the other Loan Documents, as amended hereby; (e) the
Borrower's Certificate of Incorporation and Bylaws are in full force and effect
on and as of the date hereof without modification or amendment in any respect
since November 1, 1996; (f) as of the date hereof, (i) Borrower is in existence
and in corporate and tax good standing in the State of its organization, (ii)
the Borrower is qualified to do business as a foreign corporation and is in
corporate and tax good standing in each jurisdiction where Borrower is doing
business and is required to be so qualified, (iii) Borrower does not owe
franchise taxes or other taxes required to maintain its corporate existence and
no franchise tax reports are due, and (iv) no proceedings are pending for
forfeiture of the Borrower's charter or for its dissolution either voluntarily
or involuntarily; and (g) the officer of Borrower executing this Amendment has
been duly elected and is, at present, qualified and acting in the office
indicated below such officer's name and is duly authorized to execute this
Amendment on behalf of Borrower.

                                   ARTICLE VI
                            Miscellaneous Provisions

     6.01 Survival of Representations and Warranties. All representations and
warranties made in the Loan Agreement or any other Loan Document, including,
without limitation, any

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document furnished in connection with this Amendment, shall survive the
execution and delivery of this Amendment and the other Loan Documents, and no
investigation by Lender or any closing shall affect the representations and
warranties or the right of Lender to rely upon them.

     6.02 Reference to Loan Agreement. Each of the Loan Agreement and the other
Loan Documents, and any and all other agreements, documents or instruments now
or hereafter executed and delivered pursuant to the terms hereof or pursuant to
the terms of the Loan Agreement, as amended hereby, are hereby amended so that
any reference in the Loan Agreement and such other Loan Documents to the Loan
Agreement shall mean a reference to the Loan Agreement, as amended hereby.

     6.03 Expenses of Lender. As provided in the Loan Agreement, Borrower agrees
to pay on demand all costs and expenses incurred by Lender in connection with
the preparation, negotiation and execution of this Amendment and the other Loan
Documents executed pursuant hereto and any and all amendments, modifications,
and supplements thereto, including, without limitation, the costs and fees of
Lender's legal counsel, and all costs and expenses incurred by Lender in
connection with the enforcement or preservation of any rights under the Loan
Agreement, as amended hereby, or any other Loan Documents, including, without,
limitation, the costs and fees of Lender's legal counsel.

     6.04 Severability. Any provision of this Amendment held by a court of
competent jurisdiction to be invalid or unenforceable shall not impair or
invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

     6.05 Successors and Assigns. This Amendment is binding upon and shall inure
to the benefit of Lender and Borrower and their respective successors and
assigns, except that Borrower may not assign or transfer any of its rights or
obligations hereunder without the prior written consent of Lender.

     6.06 Counterparts. This Amendment may be executed in one or more
counterparts, each of which when so executed shall be deemed to be an original,
but all of which when taken together shall constitute one and the same
instrument.

     6.07 Effect of Waiver. No consent or waiver, express or implied, by Lender
to or for any breach of or deviation from any covenant or condition by Borrower
shall be deemed a consent to or waiver of any other breach of the same or any
other covenant, condition or duty.

     6.08 Headings. The headings, captions, and arrangements used in this
Amendment are for convenience only and shall not affect the interpretation of
this Amendment.

     6.09 Applicable Law. THIS AMENDMENT AND ALL OTHER LOAN DOCUMENTS EXECUTED
PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE AND TO BE PERFORMABLE IN AND
SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
TEXAS.

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     6.10 Final Agreement. THE LOAN AGREEMENT AND THE OTHER LOAN DOCUMENTS, EACH
AS AMENDED HEREBY, REPRESENT THE ENTIRE EXPRESSION OF THE PARTIES WITH RESPECT
TO THE SUBJECT MATTER HEREOF ON THE DATE THIS AMENDMENT IS EXECUTED. THE LOAN
AGREEMENT AND THE OTHER LOAN DOCUMENTS, AS AMENDED HEREBY, MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS
OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES. NO
MODIFICATION, RESCISSION, WAIVER, RELEASE OR AMENDMENT OF ANY PROVISION OF THIS
AMENDMENT SHALL BE MADE, EXCEPT BY A WRITTEN AGREEMENT SIGNED BY BORROWER AND
LENDER.

     6.11 Release. BORROWER HEREBY ACKNOWLEDGES THAT IT HAS NO DEFENSE,
COUNTERCLAIM, OFFSET, CROSS-COMPLAINT, CLAIM OR DEMAND OF ANY KIND OR NATURE
WHATSOEVER THAT CAN BE ASSERTED TO REDUCE OR ELIMINATE ALL OR ANY PART OF ITS
LIABILITY TO REPAY THE "OBLIGATIONS" OR TO SEEK AFFIRMATIVE RELIEF OR DAMAGES OF
ANY KIND OR NATURE FROM LENDER. BORROWER HEREBY VOLUNTARILY AND KNOWINGLY
RELEASES AND FOREVER DISCHARGES LENDER, ITS PREDECESSORS, OFFICERS, DIRECTORS,
AGENTS, EMPLOYEES, SUCCESSORS AND ASSIGNS, FROM ALL POSSIBLE CLAIMS, DEMANDS,
ACTIONS, CAUSES OF ACTION, DAMAGES, COSTS, EXPENSES, AND LIABILITIES WHATSOEVER,
KNOWN OR UNKNOWN, ANTICIPATED OR UNANTICIPATED, SUSPECTED OR UNSUSPECTED, FIXED,
CONTINGENT, OR CONDITIONAL, AT LAW OR IN EQUITY, ORIGINATING IN WHOLE OR IN PART
ON OR BEFORE THE DATE THIS AMENDMENT IS EXECUTED, WHICH THE BORROWER MAY NOW OR
HEREAFTER HAVE AGAINST LENDER, ITS PREDECESSORS, OFFICERS, DIRECTORS, AGENTS,
EMPLOYEES, SUCCESSORS AND ASSIGNS, IF ANY, AND IRRESPECTIVE OF WHETHER ANY SUCH
CLAIMS ARISE OUT OF CONTRACT, TORT, VIOLATION OF LAW OR REGULATIONS, OR
OTHERWISE, AND ARISING FROM ANY "LOANS", INCLUDING, WITHOUT LIMITATION, ANY
CONTRACTING FOR, CHARGING, TAKING, RESERVING, COLLECTING OR RECEIVING INTEREST
IN EXCESS OF THE HIGHEST LAWFUL RATE APPLICABLE, THE EXERCISE OF ANY RIGHTS AND
REMEDIES UNDER THE LOAN AGREEMENT OR OTHER LOAN DOCUMENTS, AND THE NEGOTIATION
OF AND EXECUTION OF THIS AMENDMENT.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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     IN WITNESS WHEREOF, this Amendment has been executed and is effective as of
the date first above-written.

                                 "LENDER"

                                 FLEET CAPITAL CORPORATION

                                 By: /s/ Hance VanBeber
                                     -------------------------------------
                                 Name: Hance VanBeber
                                 Title: Vice President

                                 "BORROWER"

                                 LOWRANCE ELECTRONICS, INC.

                                 By: /s/ Darrell J. Lowrance
                                     -------------------------------------
                                     Darrell J. Lowrance, President

                                 LEI EXTRAS, INC.

                                 By: /s/ Steven L. Schneider
                                     -------------------------------------
                                     Steven L. Schneider, President

                                 LOWRANCE CONTRACTS, INC.

                                 By: /s/ Terry R. Nimmo
                                     -------------------------------------
                                     Terry R. Nimmo, Vice President

                                 SEA ELECTRONICS, INC.

                                 By: /s/ Steven L. Schneider
                                     -------------------------------------
                                     Steven L. Schneider, President

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