Exhibit 10.22

                              AMENDMENT NUMBER 1
                                      to
                         SYNTRON, INC. - BENTHOS, INC.
                         HYDROPHONE LICENSE AGREEMENT



This Amendment Number 1 modifies the SYNTRON, INC. - BENTHOS, INC. HYDROPHONE
LICENSE AGREEMENT in the following respects.  The SYNTRON, INC. - BENTHOS, INC.
HYDROPHONE LICENSE AGREEMENT and this Amendment Number 1 shall be referred to
collectively as the "Agreement".  LICENSOR and LICENSEE agree as follows:

1.  Replace ARTICLE IV in its entirety with:


ARTICLE IV - FEE, COST BASIS/REMUNERATION, ROYALTIES, AND REPORTING

4.1.  For the rights, privileges and license granted hereunder, LICENSEE shall
      pay a license fee, provide engineering services, provide preferred selling
      price and delivery status, and pay royalties to LICENSOR in the manner
      hereinafter provided to the end of the term of the Proprietary Rights,
      which shall be until the last patent to expire of all patents included
      within Proprietary Rights, or until this Agreement shall be terminated as
      hereinafter provided:

      (A)    LICENSEE agrees to pay LICENSOR a License Issue fee in the amount
             of Ten Dollars ($10.00);

      (B.1)  LICENSEE shall provide engineering services to complete the
             engineering required to place the Licensed Product in a high volume
             manufacturing design state including without limitation the
             generation of the Documentation. Such services shall include all
             engineering design, manufacturing design, the generation and
             copying of the Documentation and any future updates thereto as and
             when initiated by LICENSEE and prototype materials required to
             fabricate parts for proof of design. Such services shall be deemed
             initially completed by LICENSEE on 1) the successful completion of
             testing to the satisfaction of LICENSOR and LICENSEE to a mutually
             agreed upon set of performance specifications documented in
             Appendix B attached hereto and made a part hereof and 2) delivery
             to LICENSOR by LICENSEE of a complete and accurate reproducible
             copy of the then current Documentation.

             The work product of LICENSEE's services, including results, and all
             ideas, plans, developments, and inventions which LICENSEE conceives
             or reduces to practice during the course of performance under this
             subparagraph 4.1.(B) and this Agreement shall be the exclusive
             property of LICENSOR. This information, material, plans, and any
             such ideas or inventions shall be deemed LICENSOR Proprietary
             Information and shall not be disclosed to anyone outside of
             LICENSOR or used by LICENSEE outside the terms and conditions of
             this Agreement or used by others without the prior written consent
             of LICENSOR. Such work product which qualifies as a "work for hire"
             under the copyright laws of the United States shall be the
             exclusive property of LICENSOR as "work for hire". All right,
             title, and interest, including any copyright in and to any written
             data which does not qualify as a "work-for-hire" shall be deemed to
             have been automatically transferred to LICENSOR from the date of
             inception thereof. Upon LICENSOR's 

 
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Syntron, Inc. - Benthos, Inc.
Hydrophone License Agreement
Amendment Number 1


             request, LICENSEE shall execute any document and render such other
             assistance as reasonably necessary to perfect full right, title,
             and interest worldwide in the written data, including formal
             conveyance of copyright. Written data shall not be published or
             submitted for publication by LICENSEE without the prior written
             approval of LICENSOR. Further, if any such article, paper,
             treatise, or report includes work previously copyrighted by
             LICENSEE, LICENSEE hereby grants to LICENSOR a nonexclusive,
             worldwide, irrevocable, paid-up license under such copyrights to
             reproduce, distribute, and use the works in any manner.

             During the period of this Agreement and thereafter at any
             reasonable time when called upon to do so by LICENSOR, LICENSEE
             shall execute patent applications, assignments to LICENSOR, and
             other papers and shall render such other assistance that LICENSOR
             believes necessary to secure for LICENSOR the full protection and
             ownership of all rights in and to the work product of the services
             performed by LICENSEE. The filing of patent applications on
             inventions made by LICENSEE shall be decided by LICENSOR and shall
             be for such countries as LICENSOR shall elect. LICENSOR shall bear
             all the expenses in connection with the preparation, filing, and
             prosecution of applications for patents and for all matters
             provided in this subparagraph requiring the time and/or assistance
             of LICENSEE as to inventions. Further, LICENSOR shall pay LICENSEE
             the hourly rate of $ 75.00 for services which LICENSEE performs in
             connection with inventions and patent applications which may be
             required by LICENSOR whether during the term of this Agreement or
             after expiration or termination of this Agreement. LICENSEE
             warrants that the engineering design, manufacturing design, the
             generation and copying of the Documentation and any future updates
             thereto shall not violate any third party's intellectual property
             rights nor include any unauthorized disclosure of any third party's
             intellectual property and agrees to, at its sole expense, at all
             times during the term of this Agreement and thereafter indemnify,
             defend, and hold LICENSOR, their trustees, officers, employees and
             affiliates harmless against any and all costs and/or liabilities of
             whatever nature that may result from any claim by any third party
             for infringement of such third party's intellectual property
             rights. The aforementioned documentation deemed "work for hire"
             shall be clearly marked as the property and proprietary information
             of LICENSOR.

      (B.2)  LICENSEE shall provide engineering services to determine what
             production tooling will be necesary and provide such production
             tooling required by LICENSEE or LICENSEE's subcontractors to
             produce the Licensed Product. Such services shall include all
             engineering design and manufacturing for production tooling
             required by LICENSEE or LICENSEE's subcontractors and any future
             updates thereto as and when initiated by LICENSEE to produce the
             Licensed Product. Such services shall be deemed initially completed
             by LICENSEE on 1) the successful completion of testing to the
             satisfaction of LICENSOR and LICENSEE of Licensed Product
             manufactured using the production tooling to be tested to a
             mutually agreed upon set of performance specifications documented
             in Appendix B attached hereto and made a part hereof and 2)
             delivery to LICENSOR by LICENSEE of a complete and accurate listing
             of such production tooling with values per individual item. Title
             to such production tooling provided by LICENSEE to itself and its
             subcontractors shall be held by LICENSEE. LICENSEE shall be
             responsible for maintenance and replacement of such production
             tooling as required.

      (C)    LICENSEE shall manufacture the Licensed Product to the
             specifications agreed to for the use of LICENSOR and all other
             customers that may have a need for this product regardless of these
             other customers competitive position with LICENSOR.

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Syntron, Inc. - Benthos, Inc.
Hydrophone License Agreement
Amendment Number 1


      (D)    In consideration of granting said exclusive license to LICENSEE,
             LICENSEE will provide most favored customer status to LICENSOR with
             respect to any selling price and delivery of the Licensed Product
             to LICENSOR. NO ROYALTIES ARE DUE LICENSOR ON THE VALUE OF PRODUCTS
             SOLD TO LICENSOR. At all times that this license is exclusive to
             LICENSEE, LICENSOR will not compete with LICENSEE in the Licensed
             Product as an saleable end-item.

      (E)    LICENSEE is free to set the unit sales price of the Licensed
             Product to any LICENSEE customer. The foregoing notwithstanding and
             by way of indication of most favored customer status of LICENSOR,
             the Net Selling Price of such unit sales price to any third party
             will not be lower at any time than the actual gross selling price
             to LICENSOR for like or lesser quantity purchase commitment.

      (F)    For all sales of the Licensed Product to any organization or entity
             other than LICENSOR up to the combined, cummulative amount of the
             first 250,000 units, LICENSEE shall not be required to pay any
             running Royalties to LICENSOR. For all sales of the Licensed
             Product to any organization or entity other than LICENSOR following
             such first 250,000 units, LICENSEE shall pay to LICENSOR running
             Royalties in the amount of $0.75 per unit for each Commercial Sale
             of Licensed Products by LICENSEE - said Royalty to be due and
             payable upon delivery of the report due pursuant to Paragraph 4.5
             hereof. In the event a Commercial Sale of Licensed Products occurs
             together with the sale or lease of a system or other product, such
             royalty shall be solely on the Licensed Product, as no royalty
             shall be payable with respect to any other portion of such system
             or product.

4.2  No multiple royalties shall be payable solely for the reason that any
     Licensed Products, its manufacture, use, or sale are or shall be covered by
     more than one patent application, patent or certificate of registration
     licensed under this Agreement.

4.3  Royalty payments shall be paid in United States dollars in Houston, Texas,
     or at such other place as LICENSOR may reasonably designate.

4.4  LICENSEE shall keep full, true and accurate books of account and records
     containing all particulars that may be necessary for the purposes of
     showing the amounts payable to or by LICENSOR hereunder. Said books of
     account shall be kept at LICENSEE's principal place of business or the
     principal place of business of the appropriate division of LICENSEE to
     which this Agreement relates. Said books and the supporting data shall be
     open at all reasonable times for three (3) years following the end of the
     calendar year to which they pertain, to the inspection of independent CPA's
     to be proposed by LICENSOR and approved by LICENSEE, said approval not to
     be unreasonably withheld, for the purpose of verifying LICENSEE's royalty
     statement or compliance in other respects with this Agreement, such
     inspection to occur no more than once each calendar year upon reasonable
     prior notice to LICENSEE. The expense of such inspection shall be borne by
     LICENSOR unless such inspection reveals a shortfall in payments due to
     LICENSOR by LICENSEE or other violation of the terms and conditions of this
     Agreement by LICENSEE in which case such expenses shall be borne by
     LICENSEE.

4.5  The Royalty provided in Paragraph 4.1(F) shall be payable to LICENSOR
     within in one (1) month after the end of each calendar quarter. LICENSEE
     shall have the option of paying any portions of the 

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Syntron, Inc. - Benthos, Inc.
Hydrophone License Agreement
Amendment Number 1


     royalty herein provided at any time earlier than that specified. Each
     royalty payment to LICENSOR shall include an appropriate statement of the
     gross revenues due LICENSOR and shall identify the portion of the Agreement
     under which said royalty payments are made. In addition, each royalty
     payment shall be accompanied by true and accurate reports giving such
     particulars of the business conducted by LICENSEE during the period to
     which such payment applies under this Agreement ending thirty (30) days
     prior to such payment date as shall be pertinent to an accounting
     hereunder.

4.6  The royalty payments set forth in this Agreement shall, if overdue, bear
     interest until payment at the maximum per annum rate permitted by
     applicable law. The payment of such interest shall not foreclose LICENSOR
     from exercising any other rights it may have as a consequence of the
     lateness of any payment.

2.   Replace Appendix A dated October 16, 1997 in its entirety with Appendix A
     dated June 18, 1998.


3.   Replace Appendix B Revision E dated October 17, 1997 in its entirety with
     Appendix B Revision G dated May 26, 1998.

4.  All other terms and conditions of the Agreement remain unchanged.


IN WITNESS THEREOF, the parties have hereunto set their hands and duly executed
this Amendment Number 1 as of the day and year set forth below.


AGREED ON BEHALF OF                      AGREED ON BEHALF OF
SYNTRON, INC. (LICENSOR)                 BENTHOS, INC. (LICENSEE)

By: /s/ RICHARD  F. MILES                By: /s/ JOHN L. COUGHLIN
    -----------------------                  ----------------------
    Name:  RICHARD F. MILES                  Name:  JOHN L. COUGHLIN
    Title: President                         Title: President/CEO
    Date:  September 11, 1998                Date:  9-9-98

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