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                                                                    EXHIBIT 10.9

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

                            Dated as of March 1, 1996

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Debtor(s)                                                  Secured Party

<S>                                                        <C>
BEARCOM OPERATING, L.P.                                    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")
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         WHEREAS, Debtor and Secured Party desire to amend and restate that
certain Commercial Security Agreement dated December 29, 1995 executed by Debtor
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 Renewal Master Revolving
                        Credit Note of even date herewith in the original
                        principal sum of $9,000,000.00, executed by Debtor and
                        payable to the order of Secured Party, and any and all
                        extensions, renewals, modifications and rearrangements
                        thereof; (ii) certain obligations of Debtor to Secured
                        Party under that certain Second Amended and Restated
                        Loan Agreement of even date herewith between Debtor and
                        Secured Party and all extensions, renewals,
                        modifications and rearrangements thereof; and (iii) 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;


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______ Farming operations.

                  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

[ ]       [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).

                        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 and effect, and shall not be rescinded,
                                revoked, terminated,


                                       11
<PAGE>   12

                                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 its use and benefit to complete,
                                execute and file with the United

                                       12
<PAGE>   13

                                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:


                                       13
<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.


                                       16
<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.


                                       19
<PAGE>   20

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

                                       "Debtor"

                                       BEARCOM OPERATING, L.P.

                                       By:      PageCom GP, Inc.,
                                                in its capacity as
                                                general partner



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










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