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                                                                    EXHIBIT 10.7


               AMENDED AND RESTATED COMMERCIAL SECURITY AGREEMENT
                        (FIBT Form 000-70034 (Rev. 9/86))

                            Dated as of March 1, 1996


Debtor(s)                                   Secured Party

BEARCOM, INC.                               First Interstate Bank of Texas, N.A.
11545 Pagemill Road                         1445 Ross Avenue
Dallas, Texas 75243                         Dallas, Texas 75202
(HEREINAFTER REFERRED TO AS "DEBTOR"        (HEREINAFTER REFERRED TO AS "SECURED
WHETHER ONE OR MORE)                        PARTY")

         WHEREAS, Debtor and Secured Party desire to amend and restate that
certain Commercial Security Agreement dated October 2, 1994 executed by Debtor
(f/k/a Page-Com, Inc.) in favor of Secured Party;

         FOR VALUE RECEIVED, the receipt and sufficiency of which is hereby
acknowledged, Debtor grants to Secured Party the security interest (and the
pledges and assignments as applicable) hereinafter set forth and agrees with
Secured Party as follows:

              a.        OBLIGATIONS SECURED.  The security interest and pledges
                   and assignments as applicable granted hereby are to secure
                   punctual payment and performance of the following: (i) that
                   certain Guaranty Agreement of even date herewith executed by
                   Debtor in favor of Secured Party, and any and all extensions,
                   renewals, modifications and rearrangements thereof; and (ii)
                   any and all other indebtedness, liabilities and obligations
                   whatsoever and of whatever nature of Debtor to Secured Party
                   whether direct or indirect, absolute or contingent, primary
                   or secondary, due or to become due and whether now existing
                   or hereafter arising and howsoever evidenced or acquired,
                   whether joint or several, or joint and several (all of which
                   are herein separately and collectively referred to as the
                   "Obligations"). Debtor acknowledges that the security
                   interest (and pledges and assignments as applicable) hereby
                   granted shall secure all future advances from Secured Party
                   to BearCom, Inc., as well as any and all other indebtedness,
                   liabilities and obligations of Debtor to Secured Party
                   whether now in existence or hereafter arising.

              b.        USE OF COLLATERAL. Debtor represents, warrants and
                   covenants that the Collateral will be used by the Debtor
                   primarily for business use, unless otherwise specified as
                   follows:

______ Personal, family or household purposes;
______ Farming operations.

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              c.        DESCRIPTION OF COLLATERAL. Debtor hereby grants to
                   Secured Party a security interest in (and hereby pledges and
                   assigns as applicable) and agrees that Secured Party shall
                   continue to have a security interest in (and a pledge and
                   assignment as applicable), the following property, to-wit:

(DEBTOR TO INITIAL APPROPRIATE BLANKS)

          [X]      ALL ACCOUNTS. A security interest in all accounts now owned
  ---     ---      or existing as well as any and all that may hereafter arise
                   or be acquired by Debtor, and all the proceeds and products
                   thereof, including without limitation, all notes, drafts,
                   acceptances, instruments and chattel paper arising therefrom,
                   and all returned or repossessed goods arising from or
                   relating to any such accounts, or other proceeds of any sale
                   or other disposition of inventory.

          [X]      ALL INVENTORY. A security interest in all of Debtor's
  ---     ---      inventory, including all goods, merchandise, raw materials,
                   goods in process, finished goods and other tangible personal
                   property, wheresoever located, now owned or hereafter
                   acquired and held for sale or lease or furnished or to be
                   furnished under contracts for service or used or consumed in
                   Debtor's business and all additions and accessions thereto
                   and contracts with respect thereto and all documents of title
                   evidencing or representing any part thereof, and all products
                   and proceeds thereof, including, without limitation, all of
                   such which is now or hereafter located at the following
                   locations: (give locations)

                           11545 Pagemill Road
                           Dallas, Texas 75243

                           3505 Cadillac Avenue
                           Costa Mesa, California 92626

          [X]      ALL EQUIPMENT. A security interest in all equipment of every
  ---     ---      nature and description whatsoever now owned or hereafter
                   acquired by Debtor including all appurtenances and additions
                   thereto and substitutions therefor, wheresoever located,
                   including all tools, parts and accessories used in connection
                   therewith.

          [X]      GENERAL INTANGIBLES. A security interest in all general
  ---     ---      intangibles and other personal property now owned or
                   hereafter acquired by Debtor other than goods, accounts,
                   chattel paper, documents and instruments.

          [X]      CHATTEL PAPER. A security interest in all of Debtor's
  ---     ---      interest under chattel paper, lease agreements and other
                   instruments or documents, whether now existing or owned by
                   Debtor or hereafter arising or acquired by Debtor, evidencing
                   both a debt and security interest in or lease of specific
                   goods.



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          [X]      INSTRUMENTS. A pledge and assignment of and security interest
  ---     ---      in all of Debtor's now owned or existing as well as hereafter
                   acquired or arising instruments and documents.

  ---     ---      OTHER. A security interest in all of Debtor's interest, now
                   owned or hereafter acquired, in and to the property described
                   below: (give description)

         The term "Collateral" as used in this Agreement shall mean and include,
and the security interest (and pledge and assignment as applicable) shall cover,
all of the foregoing property, as well as any accessions, additions and
attachments thereto and the proceeds and products thereof, including without
limitation, all cash, general intangibles, accounts, inventory, equipment,
fixtures, farm products, notes, drafts, acceptances, securities, instruments,
chattel paper, insurance proceeds payable because of loss or damage, or other
property, benefits or rights arising therefrom, and in and to all returned or
repossessed goods arising from or relating to any of the property described
herein or other proceeds of any sale or other disposition of such property.

         As additional security for the punctual payment and performance of the
Obligations, and as part of the Collateral, Debtor hereby grants to Secured
Party a security interest in, and a pledge and assignment of, any and all money,
property, deposit accounts, accounts, securities, documents, chattel paper,
claims, demands, instruments, items or deposits of the Debtor, and each of them,
or to which any of them is a party, now held or hereafter coming within Secured
Party's custody or control, including, without limitation, all certificates of
deposit and other depository accounts, whether such have matured or the exercise
of Secured Party's rights results in loss of interest or principal or other
penalty on such deposits, but excluding deposits subject to tax penalties if
assigned. Without prior notice to or demand upon the Debtor, Secured Party may
exercise its rights granted above at any time when a default has occurred or
Secured Party deems itself insecure. Secured Party's rights and remedies under
this paragraph shall be in addition to and cumulative of any other rights or
remedies at law and equity, including, without limitation, any rights of set-off
to which Secured Party may be entitled.

              d.        REPRESENTATIONS, WARRANTIES AND COVENANTS OF DEBTOR.
                   Debtor represents and warrants as follows:

                   i.        OWNERSHIP; NO ENCUMBRANCES. Except for the
                        security interest (and pledges and assignments as
                        applicable) granted hereby, the Debtor is, and as to any
                        property acquired after the date hereof which is
                        included within the Collateral, Debtor will be, the
                        owner of all such Collateral free and clear from all
                        charges, liens, security interests, adverse claims and
                        encumbrances of any and every nature whatsoever.

                   ii.       NO FINANCING STATEMENTS. There is no financing
                        statement or similar filing now on file in any public
                        office covering any part of the Collateral, and Debtor
                        will not execute and there will not be on file in any
                        public office any financing statement or similar filing


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                        except the financing statements filed or to be filed in
                        favor of Secured Party.

                   iii.      ACCURACY OF INFORMATION. All information furnished
                        to Secured Party concerning Debtor, the Collateral and
                        the Obligations, or otherwise for the purpose of
                        obtaining or maintaining credit, is or will be at the
                        time the same is furnished, accurate and complete in all
                        material respects.

                   iv.       AUTHORITY.  Debtor has full right and authority to
                        execute and perform this Agreement and to create the
                        security interest (and pledges and assignment as
                        applicable) created by this Agreement. The making and
                        performance by Debtor of this Agreement will not violate
                        any articles of incorporation, bylaws or similar
                        document respecting Debtor, any provision of law, any
                        order of court or governmental agency, or any indenture
                        or other agreement to which Debtor is a party, or by
                        which Debtor or any of Debtor's property is bound, or be
                        in conflict with, result in a breach of or constitute
                        (with due notice and/or lapse of time) a default under
                        any such indenture or other agreement, or result in the
                        creation or imposition of any charge, lien, security
                        interest, claim or encumbrance of any and every nature
                        whatsoever upon the Collateral, except as contemplated
                        by this Agreement.

                   v.        ADDRESSES. The address of Debtor designated at the
                        beginning of this Agreement is Debtor's place of
                        business if Debtor has only one place of business;
                        Debtor's chief executive office if Debtor has more than
                        one place of business; or Debtor's residence if Debtor
                        has no place of business. Debtor agrees not to change
                        such address without advance written notice to Secured
                        Party.

              e.        GENERAL COVENANTS.  Debtor covenants and agrees as
                   follows:

                   i.        OPERATION OF THE COLLATERAL.  Debtor agrees to
                        maintain and use the Collateral solely in the conduct of
                        its own business, in a careful and proper manner, and in
                        conformity with all applicable permits or licenses.
                        Debtor shall comply in all respects with all applicable
                        statutes, laws, ordinances and regulations. Debtor shall
                        not use the Collateral in any unlawful manner or for any
                        unlawful purposes, or in any manner or for any purpose
                        that would expose the Collateral to unusual risk, or to
                        penalty, forfeiture or capture, or that would render
                        inoperative any insurance in connection with the
                        Collateral.


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                   ii.       CONDITION. Debtor shall maintain, service and
                        repair the Collateral so as to keep it in good operating
                        condition. Debtor shall replace within a reasonable time
                        all parts that may be worn out, lost, destroyed or
                        otherwise rendered unfit for use, with appropriate
                        replacement parts. Debtor shall obtain and maintain in
                        good standing at all times all applicable permits,
                        licenses, registrations and certificates respecting the
                        Collateral.

                   iii.      ASSESSMENTS. Debtor shall promptly pay when due all
                        taxes, assessments, license fees, registration fees, and
                        governmental charges levied or assessed against Debtor
                        or with respect to the Collateral or any part thereof.

                   iv.       NO ENCUMBRANCES. Debtor agrees not to suffer or
                        permit any charge, lien, security interest, adverse
                        claim or encumbrance of any and every nature whatsoever
                        against the Collateral or any part thereof.

                   v.        NO REMOVAL. Except as otherwise provided in this
                        Agreement, Debtor shall not remove the Collateral from
                        the county or counties designated at the beginning of
                        this Agreement without Secured Party's prior written
                        consent.

                   vi.       NO TRANSFER. Except as otherwise provided in this
                        Agreement with respect to inventory, Debtor shall not,
                        without the prior written consent of Secured Party,
                        sell, assign, transfer, lease, charter, encumber,
                        hypothecate or dispose of the Collateral, or any part
                        thereof, or interest therein, or offer to do any of the
                        foregoing.

                   vii.      NOTICES AND REPORTS.  Debtor shall promptly notify
                        Secured Party in writing of any change in the name,
                        identity or structure of Debtor, any charge, lien,
                        security interest, claim or encumbrance asserted against
                        the Collateral, any litigation against Debtor or the
                        Collateral, any theft, loss, injury or similar incident
                        involving the Collateral, and any other material matter
                        adversely affecting Debtor or the Collateral. Debtor
                        shall furnish such other reports, information and data
                        regarding Debtor's financial condition and operations,
                        the Collateral and such other matters as Secured Party
                        may request from time to time.

                   viii.     LANDLORD'S WAIVERS. Debtor shall furnish to Secured
                        Party, if requested, a landlord's waiver of all liens
                        with respect to any Collateral covered by this Agreement
                        that is or may be located upon leased premises, such
                        landlord's waivers to be in such form and upon such
                        terms as are acceptable to Secured Party.


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                   ix.       ADDITIONAL FILINGS. Debtor agrees to execute and
                        deliver such financing statement or statements, or
                        amendments thereof or supplements thereto, or other
                        documents as Secured Party may from time to time require
                        in order to comply with the Texas Uniform Commercial
                        Code (or other applicable state law of the jurisdiction
                        where any of the Collateral is located) and to preserve
                        and protect the Secured Party's rights to the
                        Collateral.

                   x.        PROTECTION OF COLLATERAL.  Secured Party, at its
                        option, whether before or after default, but without any
                        obligation whatsoever to do so, may (a) discharge taxes,
                        claims, charges, liens, security interests, assessments
                        or other encumbrances of any and every nature whatsoever
                        at any time levied, placed upon or asserted against the
                        Collateral, (b) place and pay for insurance on the
                        Collateral, including insurance that only protects
                        Secured Party's interest, (c) pay for the repair,
                        improvement, testing, maintenance and preservation of
                        the Collateral, (d) pay any filing, recording,
                        registration, licensing or certification fees or other
                        fees and charges related to the Collateral, or (e) take
                        any other action to preserve and protect the Collateral
                        and Secured Party's rights and remedies under this
                        Agreement as Secured Party may deem necessary or
                        appropriate. Debtor agrees that Secured Party shall have
                        no duty or obligation whatsoever to take any of the
                        foregoing action. Debtor agrees to promptly reimburse
                        Secured Party upon demand for any payment made or any
                        expense incurred by the Secured Party pursuant to this
                        authorization. These payments and expenditures, together
                        with interest thereon from date incurred until paid by
                        Debtor at the maximum contract rate allowed under
                        applicable laws, which Debtor agrees to pay, shall
                        constitute additional Obligations and shall be secured
                        by and entitled to the benefits of this Agreement.

                   xi.       INSPECTION. Debtor shall at all reasonable times
                        allow Secured Party by or through any of its officers,
                        agents, attorneys or accountants, to examine the
                        Collateral, wherever located, and to examine and make
                        extracts from Debtor's books and records.

                   xii.      FURTHER ASSURANCES. Debtor shall do, make, procure,
                        execute and deliver all such additional and further
                        acts, things, deeds, interests and assurances as Secured
                        Party may require from time to time to protect, assure
                        and enforce Secured Party's rights and remedies.



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                   xiii.     INSURANCE.  Debtor shall have and maintain
                        insurance at all time with respect to all tangible
                        Collateral insuring against risks of fire (including
                        so-called extended coverage), theft and other risks as
                        Secured Party may require, containing such terms, in
                        such form and amounts and written by such companies as
                        may be satisfactory to Secured Party, all of such
                        insurance to contain loss payable clauses in favor of
                        Secured Party as its interest may appear. All policies
                        of insurance shall provide for ten (10) days' written
                        minimum cancellation notice to Secured Party and at the
                        request of Secured Party shall be delivered to and held
                        by it. Secured Party is hereby authorized to act as
                        attorney for Debtor in obtaining, adjusting, settling
                        and canceling such insurance and endorsing any drafts or
                        instruments. Secured Party shall be authorized to apply
                        the proceeds from any insurance to the Obligations
                        secured hereby whether or not such Obligations are then
                        due and payable. Debtor specifically authorizes Secured
                        Party to disclose information from the policies of
                        insurance to prospective insurers regarding the
                        Collateral.

                   xiv.      ADDITIONAL COLLATERAL.  If Secured Party should at
                        any time be of the opinion that the Collateral is
                        impaired, not sufficient or has declined or may decline
                        in value, or should Secured Party deem payment of the
                        Obligations to be insecure, then Secured Party may call
                        for additional security satisfactory to Secured Party,
                        and Debtor promises to furnish such additional security
                        forthwith. The call for additional security may be oral,
                        by telegram, or United States mail addressed to Debtor,
                        and shall not affect any other subsequent right of
                        Secured Party to exercise the same.

              f.        ADDITIONAL PROVISIONS REGARDING ACCOUNTS.  The following
                   provisions shall apply to all accounts included within the
                   Collateral:

                   i.        DEFINITIONS.  The term "account", as used in this
                        Agreement, shall have the same meaning as set forth in
                        the Uniform Commercial Code of Texas in effect as of the
                        date of execution hereof, and as set forth in any
                        amendment to the Uniform Commercial Code of Texas to
                        become effective after the date of execution hereof, and
                        also shall include all present and future notes,
                        instruments, documents, general intangibles, drafts,
                        acceptances and chattel paper of Debtor, and the
                        proceeds thereof.

                   ii.       ADDITIONAL WARRANTIES. As of the time any account
                        becomes subject to the security interest (or pledge of
                        assignment as applicable) granted hereby, Debtor shall
                        be deemed further to have


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                        warranted as to each and all of such accounts as
                        follows: (a) each account and all papers and documents
                        relating thereto are genuine and in all respects what
                        they purport to be; (b) each account is valid and
                        subsisting and arises out of a bona fide sale of goods
                        sold and delivered to, or out of and for services
                        theretofore actually rendered by the Debtor to, the
                        account debtor named in the account; (c) the amount of
                        the account represented as owing is the correct amount
                        actually and unconditionally owing except for normal
                        cash discounts and is not subject to any set-offs,
                        credits, defenses or counter-charges; and (d) Debtor is
                        the owner thereof free and clear of any charges, liens,
                        security interests, adverse claims and encumbrances of
                        any and every nature whatsoever.

                   iii.      COLLECTION OF ACCOUNTS.  Secured Party shall have
                        the right in its own name or in the name of the Debtor,
                        whether before or after default, to require Debtor
                        forthwith to transmit all proceeds of collection of
                        accounts to Secured Party, to notify any and all account
                        debtors to make payments of the accounts directly to
                        Secured Party, to demand, collect, receive, receipt for,
                        sue for, compound and give acquittal for, any and all
                        amounts due or to become due on the accounts and to
                        endorse the name of the Debtor on all commercial paper
                        given in payment or part payment thereof, and in Secured
                        Party's discretion to file any claim or take any other
                        action or proceeding that Secured Party may deem
                        necessary or appropriate to protect and preserve and
                        realize upon the accounts and related Collateral. Unless
                        and until Secured Party elects to collect accounts, and
                        the privilege of Debtor to collect accounts is revoked
                        by Secured Party in writing, Debtor shall continue to
                        collect accounts, account for same to Secured Party, and
                        shall not commingle the proceeds of collection of
                        accounts with any funds of the Debtor. In order to
                        assure collection of accounts in which Secured Party has
                        a security interest (or pledge or assignment of as
                        applicable) hereunder, Secured Party may notify the post
                        office authorities to change the address for delivery of
                        mail addressed to Debtor to such address as Secured
                        Party may designate, and to open and dispose of such
                        mail and receive the collections of accounts included
                        herewith. Secured Party shall have no duty or obligation
                        whatsoever to collect any account, or to take any other
                        action to preserve or protect the Collateral; however,
                        should Secured Party elect to collect any account or
                        take possession of any Collateral, Debtor releases
                        Secured Party from any claim or claims for loss or
                        damage arising from any act or omission in connection
                        therewith.

                   iv.       IDENTIFICATION AND ASSIGNMENT OF ACCOUNTS. Upon
                        Secured Party's request, whether before or after
                        default, Debtor shall take


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                        such action and execute and deliver such documents as
                        Secured Party may reasonably request in order to
                        identify, confirm, mark, segregate and assign accounts
                        and to evidence Secured Party's interest in same.
                        Without limitation of the foregoing, Debtor, upon
                        request, agrees to assign accounts to Secured Party,
                        identify and mark accounts as being subject to the
                        security interest (or pledge or assignment as
                        applicable) granted hereby, mark Debtor's books and
                        records to reflect such assignments, and forthwith to
                        transmit to Secured Party in the form as received by
                        Debtor any and all proceeds of collection of such
                        accounts.

                   v.        ACCOUNT REPORTS.  Upon Secured Party's request,
                        Debtor will deliver to Secured Party, prior to the tenth
                        (10th) day of each month, or on such other frequency as
                        Secured Party may request, a written report in form and
                        content satisfactory to Secured Party, showing a listing
                        and aging of accounts and such other information as
                        Secured Party may request from time to time. Debtor
                        shall immediately notify Secured Party of the assertion
                        by any account debtor of any set-off, defense or claim
                        regarding an account or any other matter adversely
                        affecting an account.

                   vi.       SEGREGATION OF RETURNED GOODS.  Returned or
                        repossessed goods arising from or relating to any
                        accounts included within the Collateral shall if
                        requested by Secured Party be held separate and apart
                        from any other property. Debtor shall as often as
                        requested by Secured Party, but not less often than
                        weekly even though no special request has been made,
                        report to Secured Party the appropriate identifying
                        information with respect to any such returned or
                        repossessed goods relating to accounts included in
                        assignments or identifications made pursuant hereto.

              g.        ADDITIONAL PROVISIONS REGARDING INVENTORY. The following
                   provisions shall apply to all inventory included within the
                   Collateral:

                   i.        INVENTORY REPORTS.  Upon request by Secured Party,
                        Debtor will deliver to Secured Party, prior to the tenth
                        (10th) day of each month, or on such other frequency as
                        Secured Party may request, a written report in form and
                        content satisfactory to Secured Party, with respect to
                        the preceding month or other applicable period, showing
                        Debtor's opening inventory, inventory acquired,
                        inventory sold, inventory returned, inventory used in
                        Debtor's business, closing inventory, any other
                        inventory not within the preceding categories, and such
                        other information as Secured Party may request from time
                        to time. Debtor shall immediately notify Secured Party


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                        of any matter adversely affecting the inventory,
                        including, without limitation, any event causing loss or
                        depreciation in the value of the inventory and the
                        amount of such possible loss or depreciation.

                   ii.       LOCATION OF INVENTORY.  Debtor will promptly notify
                        Secured Party in writing of any addition to, change in
                        or discontinuance of its place(s) of business as shown
                        in this agreement, the places at which inventory is
                        located as shown herein, the location of its chief
                        executive office and the location of the office where it
                        keeps its records as set forth herein. All Collateral
                        will be located at the place(s) of business shown at the
                        beginning of this agreement as modified by any written
                        notice(s) given pursuant hereto.

                   iii.      USE OF INVENTORY.  Unless and until the privilege
                        of Debtor to use inventory in the ordinary course of
                        Debtor's business is revoked by Secured Party in the
                        event of default or if Secured Party deems itself
                        insecure, Debtor may use the inventory in any manner not
                        inconsistent with this Agreement, may sell that part of
                        the Collateral consisting of inventory provided that all
                        such sales are in the ordinary course of business, and
                        may use and consume any raw materials or supplies that
                        are necessary in order to carry on Debtor's business. A
                        sale in the ordinary course of business does not include
                        a transfer in partial or total satisfaction of a debt.

                   iv.       ACCOUNTS AS PROCEEDS. All accounts that are
                        proceeds of the inventory included within the Collateral
                        shall be subject to all of the terms and provisions
                        hereof pertaining to accounts.

                   v.        PROTECTION OF INVENTORY. Debtor shall take all
                        action necessary to protect and preserve the inventory.

              h.        ADDITIONAL PROVISIONS REGARDING SECURITIES AND SIMILAR
                   COLLATERAL. The following provisions shall apply to all
                   securities and similar property included within the
                   Collateral:

                   i.        ADDITIONAL WARRANTIES.  As to each and all
                        securities and similar property included within the
                        Collateral (including securities hereafter acquired that
                        are part of the Collateral), Debtor further represents
                        and warrants, as of the time of. delivery of same to
                        Secured Party, as follows: (a) such securities are
                        genuine, validly issued and outstanding, fully paid and
                        nonassessable, and are not issued in violation of the
                        preemptive rights of any person or of any agreement by
                        which the issuer or obligor thereof or Debtor is bound;
                        (b) such securities are not subject to any interest,
                        option or


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                        right of any third person; (c) such securities are in
                        compliance with applicable law concerning form, content
                        and manner of preparation and execution; and (d) Debtor
                        acquired and holds the securities in compliance with all
                        applicable laws and regulations.

                   ii.       DIVIDENDS AND PROCEEDS.  Any and all payments,
                        dividends, other distributions (including stock
                        redemption proceeds), or other securities in respect of
                        or in exchange for the Collateral, whether by way of
                        dividends, stock dividends, recapitalizations, mergers,
                        consolidations, stock splits, combinations or exchanges
                        of shares or otherwise, received by Debtor shall be held
                        by Debtor in trust for Secured Party and Debtor shall
                        immediately deliver same to Secured Party to be held as
                        part of the Collateral. Debtor may retain ordinary cash
                        dividends unless and until Secured Party requests that
                        same be paid and delivered to Secured Party (which
                        Secured Party may request either before or after
                        default), but shall not pay or distribute any dividends
                        to its shareholders.

                   iii.      COLLECTIONS.  Secured Party shall have the right at
                        any time and from time to time (whether before or after
                        default) to notify and direct the issuer or obligor to
                        make all payments, dividends and distributions regarding
                        the Collateral directly to Secured Party. Secured Party
                        shall have the authority to demand of the issuer or
                        obligor, and to receive and receipt for, any and all
                        payments, dividends and other distributions payable in
                        respect thereof, regardless of the medium in which paid
                        and whether they are ordinary or extraordinary. Each
                        issuer and obligor making payment to Secured Party
                        hereunder shall be fully protected in relying on the
                        written statement of Secured Party that it then holds a
                        security interest which entitles it to receive such
                        payment, and the receipt by Secured Party for such
                        payment shall be full acquittance therefor to the one
                        making such payment.

                   iv.       VOTING RIGHTS.  Upon default, or if Secured Party
                        deems itself insecure, Secured Party shall have the
                        right, at its discretion, to transfer to or register in
                        the name of Secured Party or any nominee of Secured
                        Party any of the Collateral, and/or to exercise any or
                        all voting rights as to any or all of the Collateral.
                        For such purposes, Debtor hereby names, constitutes and
                        appoints the President or any Vice President of Secured
                        Party as Debtor's proxy in the Debtor's name, place and
                        stead to vote any and all of the securities, as such
                        proxy may elect, for and in the name, place and stead of
                        Debtor, as to all matters coming before shareholders,
                        such proxy to be irrevocable and deemed coupled with an
                        interest. The rights, powers and authority of said proxy
                        shall remain in full force


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                        and effect, and shall not be rescinded, revoked,
                        terminated, amended or otherwise modified, until all
                        Obligations have been fully satisfied.

                   v.        NO DUTY.  Secured Party shall never be liable for
                        its failure to give notice to Debtor of default in the
                        payment of or upon the Collateral. Secured Party shall
                        have no duty to fix or preserve rights against prior
                        parties to the Collateral and shall never be liable for
                        its failure to use diligence to collect any amount
                        payable in respect to the Collateral, but shall be
                        liable only to account to Debtor for what it may
                        actually collect or receive thereon. Without limiting
                        the foregoing, it is specifically understood and agreed
                        that Secured Party shall have no responsibility for
                        ascertaining any maturities, calls, conversions,
                        exchanges, offers, tenders, or similar matters relating
                        to any of the Collateral or for informing Debtor with
                        respect to any of such matters (irrespective of whether
                        Secured Party actually has, or may be deemed to have,
                        knowledge thereof). The foregoing provisions of this
                        paragraph shall be fully applicable to all securities or
                        similar property held in pledge hereunder, irrespective
                        of whether Secured Party may have exercised any right to
                        have such securities or similar property registered in
                        its name or in the name of a nominee.

                   vi.       FURTHER ASSURANCES. Debtor agrees to execute such
                        stock powers, endorse such instruments, or execute such
                        additional pledge agreements or other documents as may
                        be required by the Secured Party in order effectively to
                        grant to Secured Party the security interest in (and
                        pledge and assignment of) the Collateral and to enforce
                        and exercise Secured Party's rights regarding same.

                   vii.      SECURITIES LAWS.  Debtor hereby agrees to cooperate
                        fully with Secured Party in order to permit Secured
                        Party to sell, at foreclosure or other private sale, the
                        Collateral pledged hereunder. Specifically, Debtor
                        agrees to fully comply with the securities laws of the
                        United States and of the State of Texas and to take such
                        action as may be necessary to permit Secured Party to
                        sell or otherwise transfer the securities pledged
                        hereunder in compliance with such laws. Without limiting
                        the foregoing, Debtor, at its own expense, upon request
                        by Secured Party, agrees to effect and obtain such
                        registrations, filings, statements, rulings, consents,
                        and other matters as Secured Party may request.

                   viii.     POWER OF ATTORNEY. Debtor hereby makes, constitutes
                        and appoints Secured Party or its nominee, its true and
                        lawful attorney in fact and in its name, place, and
                        stead, and on its behalf, and for


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<PAGE>   13

                        its use and benefit to complete, execute and file with
                        the United States Securities and Exchange Commission one
                        or more notices of proposed sale of securities pursuant
                        to Rule 144 under the Securities Act of 1933 and/or any
                        similar filings or notices with any applicable state
                        agencies, and said attorney in fact shall have full
                        power and authority to do, take and perform all and
                        every act and thing whatsoever requisite, proper or
                        necessary to be done, in the exercise of the rights and
                        powers herein granted, as fully to all intents and
                        purposes as Debtor might or could do if personally
                        present. This power shall be irrevocable and deemed
                        coupled with an interest. The rights, powers and
                        authority of said attorney in fact herein granted shall
                        commence and be in full force and effect from the date
                        of this agreement, and such rights, powers and authority
                        shall remain in full force and effect, and this power of
                        attorney shall not be rescinded, revoked, terminated,
                        amended or otherwise modified, until all Obligations
                        have been fully satisfied.

                   ix.       PRIVATE SALES.  Because of the Securities Act of
                        1933, as amended, or any other laws or regulations,
                        there may be legal restrictions or limitations affecting
                        Secured Party in any attempts to dispose of certain
                        portions of the Collateral in the enforcement of its
                        rights and remedies hereunder. For these reasons Secured
                        Party is hereby authorized by Debtor, but not obligated,
                        in the event any default hereunder, to sell all or any
                        part of the Collateral at private sale, subject to
                        investment letter or in any other manner which will not
                        require the Collateral, or any part thereof, to be
                        registered in accordance with the securities Act of
                        1933, as amended, or the rules and regulations
                        promulgated thereunder, or any other law or regulation.
                        Secured Party is also hereby authorized by Debtor, but
                        not obligated, to take such actions, give such notices,
                        obtain such rulings and consents, and do such other
                        things as Secured Party may deem appropriate in the
                        event of a sale or disposition of any of the Collateral.
                        Debtor clearly understands that Secured Party may in its
                        discretion approach a restricted number of potential
                        purchasers and that a sale under such circumstances may
                        yield a lower price for the Collateral or any part or
                        parts thereof than would otherwise be obtainable if same
                        were registered and sold in the open market, and Debtor
                        agrees that such private sales shall constitute a
                        commercially reasonable method of disposing of the
                        Collateral.

              i.        ADDITIONAL PROVISIONS REGARDING CERTIFICATES OF DEPOSIT
                   AND SIMILAR COLLATERAL. The following provisions shall apply
                   to certificates of deposit and similar property included
                   within the Collateral:



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<PAGE>   14



                   i.        COLLECTION OF DEPOSITS. Debtor agrees that
                        Secured Party may, at any time (whether before or after
                        default) and in its sole discretion, surrender for
                        payment and obtain payment of any portion of the
                        Collateral, whether such have matured or the exercise of
                        Secured Party's rights results in loss of interest or
                        principal or other penalty on such deposits, and, in
                        connection therewith, cause payment to be made directly
                        to Secured Party.

                   ii.       NOTICE TO THIRD PARTY ISSUER.  With regard to any
                        certificates of deposit or similar Collateral for which
                        Secured Party is not the issuer, Debtor agrees to notify
                        the issuer or obligor of the interests hereby granted to
                        Secured Party and to obtain from such issuer or obligor
                        acknowledgement of the interests in favor of Secured
                        Party and the issuer's or obligor's agreement to waive
                        in favor of Secured Party any and all rights of set-off
                        or similar rights or remedies to which such issuer or
                        obligor may be entitled, and, in connection therewith,
                        to execute and cause the issuer or obligor to execute,
                        any and all acknowledgments, waivers and other
                        agreements in such form and upon such terms as Secured
                        Party may request.

                   iii.      PROCEEDS. Any and all replacement or renewal
                        certificates, instruments, or other benefits or proceeds
                        related to the Collateral that are received by Debtor
                        shall be held by Debtor in trust for Secured Party and
                        immediately delivered to Secured Party to be held as
                        part of the Collateral.

                   iv.       NO DUTY.  Secured Party shall never be liable for
                        its failure to give notice to Debtor of default in the
                        payment of or upon the Collateral. Secured Party shall
                        have no duty to fix or preserve rights against prior
                        parties to the Collateral and shall never be liable for
                        its failure to use diligence to collect any amount
                        payable in respect to the Collateral, but shall be
                        liable only to account to Debtor for what it may
                        actually collect or receive thereon. Without limiting
                        the foregoing, it is specifically understood and agreed
                        that Secured Party shall have no responsibility for
                        ascertaining any maturities or similar matters relating
                        to any of the Collateral or for informing Debtor with
                        respect to any of such matters (irrespective of whether
                        Secured Party actually has, or may be deemed to have,
                        knowledge thereof).

              j.        EVENTS OF DEFAULT. Debtor shall be in default hereunder
                   upon the happening of any of the following events or
                   conditions: (i) non-payment when due (whether by acceleration
                   of maturity or otherwise) of any payment of principal,
                   interest or other amount due on any Obligation;


                                       14

<PAGE>   15

                   (ii) the occurrence of any event which under the terms of any
                   evidence of indebtedness, indenture, loan agreement, security
                   agreement or similar instrument permits the acceleration of
                   maturity of any obligation of Debtor or BearCom, Inc.
                   (whether to Secured Party or to others); (iii) any
                   representation or warranty made by Debtor to Secured Party in
                   connection with this Agreement, the Collateral or the
                   Obligations, or in any statements or certificates, proves
                   incorrect in any material respect as of the date of the
                   making or the issuance thereof; (iv) default occurs in the
                   observance or performance of, or if Debtor fails to furnish
                   adequate evidence of performance of, any provision of this
                   Agreement or of any note, assignment, transfer, other
                   agreement, document or instrument delivered by Debtor to
                   Secured Party in connection with this Agreement, the
                   Collateral or the Obligations; (v) death, dissolution,
                   liquidation, termination of existence, insolvency, business
                   failure or winding-up of Debtor or any maker, endorser,
                   guarantor, surety or other party liable in any capacity for
                   any of the Obligations; (vi) the commission of an act of
                   bankruptcy by, or the application for appointment of a
                   receiver or any other legal custodian for any part of the
                   property of, assignment for the benefit of creditors by, or
                   the commencement of any proceedings under any bankruptcy,
                   arrangement, reorganization, insolvency or similar laws for
                   the relief of debtors by or against, the Debtor or any maker,
                   endorser, guarantor, surety or other party primarily or
                   secondarily liable for any of the Obligations; (vii) the
                   Collateral becomes, in the judgment of Secured Party,
                   impaired, unsatisfactory or insufficient in character or
                   value; or (viii) the filing of any levy, attachment,
                   execution, garnishment or other process against the Debtor or
                   any of the Collateral or any maker, endorser, guarantor,
                   surety, or other party liable in any capacity for any of the
                   Obligations.

              k.        REMEDIES. Upon the occurrence of an event of default,
                   or if Secured Party deems payment of the Obligations to be
                   insecure, Secured Party, at its option, shall be entitled to
                   exercise any one or more of the following remedies (all of
                   which are cumulative):

                   i.        DECLARE OBLIGATIONS DUE. Secured Party, at its
                        option, may declare the Obligations or any part thereof
                        immediately due and payable, without demand, notice of
                        intention to accelerate, notice of acceleration, notice
                        of non-payment, presentment, protest, notice of
                        dishonor, or any other notice whatsoever, all of which
                        are hereby waived by Debtor and any maker, endorser,
                        guarantor, surety or other party liable in any capacity
                        for any of the Obligations.

                   ii.       REMEDIES. Secured Party shall have all of the
                        rights and remedies provided for in this Agreement and
                        in any other agreements executed by Debtor, the rights
                        and remedies of the Uniform Commercial Code of Texas,
                        and any and all of the rights


                                       15

<PAGE>   16

                        and remedies at law and in equity, all of which shall
                        be. deemed cumulative. Without limiting the foregoing,
                        Debtor agrees that Secured Party shall have the right
                        to: (a) require Debtor to assemble the Collateral and
                        make it available to Secured Party at a place designated
                        by Secured Party that is reasonably convenient to both '
                        parties, which Debtor agrees to do; (b) peaceably take
                        possession of the Collateral and remove same, with or
                        without judicial process; (c) without removal, render
                        equipment included within the Collateral unusable, and
                        dispose of the Collateral on the Debtor's premises; (d)
                        sell, lease or otherwise dispose of the Collateral, at
                        one or more locations, by public or private proceedings,
                        for cash or credit, without assumption of credit risk;
                        and/or (e) whether before or after default, collect and
                        receipt for, compound, compromise, and settle, and give
                        releases, discharges and acquittances with respect to,
                        any and all amounts owed by any person or entity with
                        respect to the Collateral. Unless the Collateral is
                        perishable or threatens to decline speedily in value or
                        is of a type customarily sold on a recognized market,
                        Secured Party will send Debtor reasonable notice of the
                        time and place of any public sale or of the time after
                        which any private sale or other disposition will be
                        made. Any requirement of reasonable notice to Debtor
                        shall be met if such notice is mailed, postage prepaid,
                        to Debtor at the address of Debtor designated at the
                        beginning of this Agreement, at least five (5) days
                        before the day of any public sale or at least five (5)
                        days before the time after which any private sale or
                        other disposition will be made.

                   iii.      EXPENSES.  Debtor shall be liable for and agrees to
                        pay the reasonable expenses incurred by Secured Party in
                        enforcing its rights and remedies, in retaking, holding,
                        testing, repairing, improving, selling, leasing or
                        disposing of the Collateral, or like expenses,
                        including, without limitation, attorneys' fees and legal
                        expenses incurred by Secured Party. These expenses,
                        together with interest thereon from date incurred until
                        paid by Debtor at the maximum contract rate allowed
                        under applicable laws, which Debtor agrees to pay, shall
                        constitute additional Obligations and shall be secured
                        by and entitled to the benefits of this Agreement.

                   iv.       PROCEEDS; SURPLUS; DEFICIENCIES. Proceeds received
                        by Secured Party from disposition of the Collateral
                        shall be applied toward Secured Party's expenses and
                        other Obligations in such order or manner as Secured
                        Party may elect. Debtor shall be entitled to any surplus
                        if one results after lawful application of the proceeds.
                        Debtor shall remain liable for any deficiency.



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<PAGE>   17

                   v.        REMEDIES CUMULATIVE. The rights and remedies of
                        Secured Party are cumulative and the exercise of any one
                        or more of the rights or remedies shall not be deemed an
                        election of rights or remedies or a waiver of any other
                        right or remedy. Secured Party may remedy any default
                        and may waive any default without waiving the default
                        remedied or without waiving any other prior or
                        subsequent default.

              l.        OTHER AGREEMENTS.

                   i.        SAVINGS CLAUSE.  Notwithstanding any provision to
                        the contrary herein, or in any of the documents
                        evidencing the Obligations or otherwise relating
                        thereto, no such provision shall require the payment or
                        permit the collection of interest in excess of the
                        maximum permitted by applicable usury laws. If any such
                        excessive interest is so provided for, then in such
                        event (i) the provisions of this paragraph shall govern
                        and control, (ii) neither the Debtor nor his heirs,
                        legal representatives, successors or assigns or any
                        other party liable for the payment thereof, shall be
                        obligated to pay the amount of such interest to the
                        extent that is in excess of the maximum amount permitted
                        by law, (iii) any such excess interest that may have
                        been collected shall be, at the option of the holder of
                        the instrument evidencing the Obligations, either
                        applied as a credit against the then unpaid principal
                        amount thereof or refunded to the maker thereof, and
                        (iv) the effective rate of interest shall be
                        automatically reduced to the maximum lawful rate under
                        applicable usury laws as now or hereafter construed by
                        the courts having jurisdiction.

                   ii.       JOINT AND SEVERAL RESPONSIBILITY. If this Security
                        Agreement is executed by more than one Debtor, the
                        obligations of all such Debtors shall be joint and
                        several.

                   iii.      WAIVERS. Debtor and any maker, endorser, guarantor,
                        surety or other party liable in any capacity respecting
                        the Obligations hereby waive demand, notice of intention
                        to accelerate, notice of acceleration, notice of
                        non-payment, presentment, protest, notice of dishonor
                        and any other similar notice whatsoever.

                   iv.       SEVERABILITY. Any provision hereof found to be
                        invalid by courts having jurisdiction shall be invalid
                        only with respect to such provision (and then only to
                        the extent necessary to avoid such invalidity). The
                        offending provision shall be modified to the maximum
                        extent possible to confer upon Secured Party the
                        benefits intended thereby. Such provision as modified
                        and the remaining


                                       17

<PAGE>   18

                        provisions hereof shall be construed and enforced to the
                        same effect as if such offending provision (or portion
                        thereof) had not been contained herein, to the maximum
                        extent possible.

                   v.        USE OF COPIES. Any carbon, photographic or other
                        reproduction of any financing statement signed by Debtor
                        is sufficient as a financing statement for all purposes,
                        including without limitation, filing in any state as may
                        be permitted by the provisions of the Uniform Commercial
                        Code of such state.

                   vi.       RELATIONSHIP TO OTHER AGREEMENTS.  This Security
                        Agreement and the security interests (and pledges and
                        assignments as applicable) herein granted are in
                        addition to (and not in substitution, novation or
                        discharge of) any and all prior or contemporaneous
                        security agreements, security interests, pledges,
                        assignments, liens, rights, titles or other interests in
                        favor of Secured Party or assigned to Secured Party by
                        others in connection with the Obligations. All rights
                        and remedies of Secured Party in all such agreements are
                        cumulative, but in the event of actual conflict in terms
                        and conditions, the terms and conditions of the latest
                        security agreement shall govern and control.

                   vii.      NOTICES. Any notice or demand given by Secured
                        Party to Debtor in connection with this Agreement, the
                        Collateral or the Obligations, shall be deemed given and
                        effective upon deposit in the United States mail,
                        postage prepaid, addressed to Debtor at the address of
                        Debtor designated at the beginning of this Agreement.
                        Actual notice to Debtor shall always be effective no
                        matter how given or received.

                   viii.     HEADINGS AND GENDER. Paragraph headings in this
                        Agreement are for convenience only and shall be given no
                        meaning or significance in interpreting this Agreement.
                        All words used herein shall be construed to be of such
                        gender or number as the circumstances require.

                   ix.       AMENDMENTS. Neither this Agreement nor any of its
                        provisions may be changed, amended, modified, waived or
                        discharged orally, but only by an instrument in writing
                        signed by the party against whom enforcement of the
                        change, amendment, modification, waiver or discharge is
                        sought.

                   x.        CONTINUING AGREEMENT. The security interest (and
                        pledges and assignments as applicable) hereby granted
                        and all of the terms and provisions in this Agreement
                        shall be deemed a continuing


                                       18

<PAGE>   19

                        agreement and shall continue in full force and effect
                        until terminated in writing. Any such revocation or
                        termination shall only be effective if explicitly
                        confirmed in a signed writing issued by Secured Party to
                        such effect and shall in no way impair or affect any
                        transactions entered into or rights created or
                        Obligations incurred or arising prior to such revocation
                        or termination as to which this Agreement shall be fully
                        operative until same are repaid and discharged in full.
                        Unless otherwise required by applicable law, Secured
                        Party shall be under no obligation to issue a
                        termination statement or similar documents unless Debtor
                        requests same in writing and, provided further, that all
                        Obligations have been repaid and discharged in full and
                        there are no commitments to make advances, incur any
                        Obligations or otherwise give value.

                   xi.       BINDING EFFECT. The provisions of this Security
                        Agreement shall be binding upon the heirs, personal
                        representatives, successors and assigns of Debtor and
                        the rights, powers and remedies of Secured Party
                        hereunder shall inure to the benefit of the successors
                        and assigns of Secured Party.

                   xii.      GOVERNING LAW.  This Security Agreement shall be
                        governed by the law of the State of Texas and applicable
                        federal law.

                   xiii.     AGREEMENT FOR BINDING ARBITRATION. DEBTOR AGREES TO
                        BE BOUND BY THE TERMS AND PROVISIONS OF THE ARBITRATION
                        PROGRAM (DATED 9/23/94) WHICH IS INCORPORATED BY
                        REFERENCE HEREIN AND IS ACKNOWLEDGED AS RECEIVED BY
                        DEBTOR PURSUANT TO WHICH ANY AND ALL DISPUTES SHALL BE
                        RESOLVED BY MANDATORY BINDING ARBITRATION UPON THE
                        REQUEST OF ANY PARTY.

EXECUTED as of this 1st day of March, 1996.

                                    "Debtor"

                                    BEARCOM, INC.

                                    By:
                                       -----------------------------------------
                                    Name:
                                         ---------------------------------------
                                    Title:
                                          --------------------------------------

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