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                                                                   EXHIBIT 10.38

                               SUBLEASE AGREEMENT


         This Agreement is made as of the 5th day of December 1997 between
Fieldworks, Inc. (a Minnesota corporation), hereinafter referred to as
"Sublessor", and LSC, Inc. (a Minnesota corporation) hereinafter referred to as
"Sublessee".


                              WITNESSETH, WHEREAS:

         Sublessor, as Tenant, entered into a lease with Northwestern Mutual
Life Insurance Co., as Landlord, dated May 13, 1994 for 12,153 square feet and a
lease dated May 10, 1994 for 12,386 square feet, and as amended on May 22, 1997
and subsequently assigned from Northwestern Mutual Life Insurance Co. to The
Principal Mutual Life Insurance Co., by sale of the building for leasing space
at 9947-9969 Valley View Road, Eden Prairie, Minnesota, (the "Building"), to
which lease (hereinafter, the "Prime Lease") reference is hereby made and a copy
is attached hereto as Exhibit B, and which is incorporated by reference as if
the same were hereinafter set forth at length; and

         The parties hereto have agreed that Sublessor shall sublet all of such
space to Sublessee;

         Now, therefore, the parties hereto hereby covenant and agree as
follows:

1)       Sublessor hereby subleases to Sublessee approximately 11,588 square
         feet of the space in said Building, described as the office area only
         of Bay B and the entire Bay C as depicted on Exhibit A attached hereto
         and made a part hereof, (the "Subleased Premises") for a term beginning
         February 1, 1998 and ending June 30, 1999 at a gross rental rate of
         Eight Thousand Five Hundred and 00/100 Dollars ($8,500.00) per month.
         Sublessee shall pay said gross rent provided for hereunder in monthly
         installments in advance on the first day of each and every month during
         the term hereof, commencing February 1, 1998, to the Sublessor at the
         address in Article 12. For the purpose of this agreement, Gross Rent
         shall include all amounts due to Sublessor, including base rent, common
         area maintenance expenses, real estate taxes, utilities, and any
         repairs required to the HVAC systems serving the Subleased Premises.
         Garbage removal, janitorial services and phone hook-ups shall be in the
         name of Sublessee and paid for directly by Sublessee commencing
         February 1, 1998.


2)       The Subleased Premises shall be used for the purposes of general office
         and warehouse.


3)       Sublessee shall not assign its interest in this Sublease nor further
         sublet the Subleased Premises in whole or in part; and shall not permit
         its interest in this Sublease to be vested in any third party by
         operation of law or otherwise, without written permission from
         Sublessor and Landlord.


4)       This Sublease is subject and subordinate to the Prime Lease. Except as
         may be inconsistent with the terms hereof, all terms, covenants and
         conditions contained in the Prime Lease shall be 
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Sublease Agreement
Page 2

         applicable to this Sublease with the same force and effect as if
         Sublessor were the Landlord under the Prime Lease and Sublessee were
         the Tenant thereunder, and in case of any breach hereof by Sublessee,
         Sublessor shall have all rights against Sublessee as would be available
         to the Landlord against the Tenant under the Prime Lease if such breach
         were by the Tenant thereunder (subject to Sublessee's limited repair
         obligation).


5)       Notwithstanding anything to the contrary herein set forth, the only
         services or rights to which Sublessee may be entitled hereunder are
         those to which Sublessor may be entitled under the Prime Lease.


6)       Sublessee and Sublessor shall neither do nor permit anything to be done
         which would cause the Prime Lease to be terminated or forfeited by
         reason of any right of termination or forfeiture reserved or vested in
         the Landlord under the Prime Lease. Sublessee and Sublessor shall
         indemnify and hold each other harmless from and against all claims or
         expenses of any kind whatsoever by reason of the other parties breach
         of the Prime Lease or this Sublease.


7)       Sublessee has paid Sublessor on the execution and delivery of this
         Sublease the sum of Eight Thousand Five Hundred and 00/100 ($8,500.00)
         as security for the full and faithful performance of the terms,
         covenants and conditions of this sublease on Sublessee's part to be
         performed or observed, including but not limited to payment of gross
         rent in default or for any other sum which Sublessor may expend or be
         required to expend by reason of Sublessee's default, including any
         damages or deficiency in reletting the Subleased Premises, in whole or
         in part, whether such damages shall accrue before or after summary
         proceedings or other re-entry by Sublessor or the Prime Landlord. If
         Sublessee shall fully and faithfully comply with all the terms,
         covenants and conditions of this sublease on Sublessee's part to be
         performed or observed, the security, or any unapplied balance thereof,
         shall be returned to Sublessee within thirty (30) days after the time
         fixed as the expiration of the demised term and after the removal of
         Sublessee and surrender of possession of the Subleased Premises to
         Sublessor in the condition that existed at the Commencement of the
         Sublease, normal wear and tear excepted.


8)       Sublessor agrees to demise the Subleased Premises as shown in Exhibit
         A, patch any holes in the existing walls, re-paint the office walls,
         shampoo the carpet and re-key the Subleased Premises. Other than the
         improvements described above, Sublessee agrees to accept the Subleased
         Premises in its "as-is" condition. Any other improvements to the
         premises, including the costs to re-wire the telephone equipment,
         security systems or computer equipment, shall be completed by the
         Sublessee, at Sublesee's sole cost and expense, with Sublessor's prior
         written approval.


9)       It is expressly agreed that Sublessor shall have no responsibility or
         liability for damage caused to any inventory or personal property
         placed by Sublessee in the Subleased Premises except for liability
         resulting from Sublessor's negligence or misconduct, and Sublessee
         agrees to carry, at its own expense, adequate inventory insurance and
         public liability insurance. Sublessee shall comply 
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Sublease Agreement
Page 3

         with all Tenant's insurance obligations under Article 16 of the Prime
         Lease. Sublessor and Landlord shall be named as additional insureds.


10)      Sublessee represents that it has read and is familiar with the terms of
         the Prime Lease and all related documents found in Exhibit B. Sublessor
         represents these are all documents relevant to the existing Lease of
         the Subleased Premises.


11)      All prior understandings and agreements between the parties are merged
         within this agreement, which alone fully and completely set forth the
         understanding of the parties; and this Sublease may not be changed or
         terminated orally or in any manner other than by an agreement in
         writing to which the written consent of the Landlord under the Prime
         Lease shall have been obtained.


12)      Any notice or demand which either party may or must give to the other
         hereunder shall be in writing and delivered personally or sent by
         certified mail, return receipt requested, addressed to Sublessor as
         follows:
                                    Fieldworks, Inc.
                                    7631 Anagram Drive
                                    Eden Prairie, MN 55344

         and to Sublessee, as follows:

                                    LSC, Inc.
                                    9955 Valley View Road
                                    Eden Prairie, MN 55344


         with a copy thereof to the Landlord under the Prime Lease in the manner
         and at the place designated in the Prime Lease. Either party may, by
         notice in writing, direct that future notices or demands to be sent to
         a different address. Sublessor agrees to notify Sublessee within five
         (5) days in the event any notice of default is received from the Prime
         Lessor which affects the Subleased Premises.


13)      Sublessor agrees as a condition of the Sublease to allow Sublessee to
         use the existing security system and telephone system (with voice mail)
         during the term of this Sublease Agreement, at no additional cost to
         Sublessee. Additionally, Sublessor agrees to give to Sublessee the two
         existing refrigerators and microwave ovens as a condition of this
         Sublease Agreement.


14)      The covenants and agreements herein contained shall bind and inure to
         the benefit of Sublessor, Sublessee and their respective heirs,
         executors, administrators, successors and assigns.
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15)      Sublessor represents it is in full compliance with Article 37 of the
         Prime Lease and to the best of Sublessor's knowledge, no hazardous
         materials are currently being stored in nor will any hazardous
         materials be left in the Subleased Premises upon Sublessor's vacation
         of the Subleased Premises.


16)      Sublessor will allow Sublessee to install signage that complies with
         the Prime Lease.


SUBLESSEE:                                   SUBLESSOR:

LSC, INC.                                    FIELDWORKS, INC.
(A MINNESOTA CORPORATION)                    (A MINNESOTA CORPORATION)

By:   /S/ BRAD BALOGH                        By:     /S/ KAREN L. ENGEBRETSON
Its:     PRESIDENT/CEO                       Its:         CFO/ VP OF FINANCE
Date:    DECEMBER 10, 1997                   Date:         DECEMBER 11, 1997