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                                                                    EXHIBIT 10.5

                   FOURTH AMENDED AND RESTATED LOAN AGREEMENT

         This Fourth Amended and Restated Loan Agreement (this "Agreement") is
entered into as of August 29, 1997 by and between BEARCOM OPERATING, L.P. (the
"Company") and WELLS FARGO BANK (TEXAS), NATIONAL ASSOCIATION, formerly First
Interstate Bank of Texas, N.A. (the "Bank").

                                    Recitals

         WHEREAS, the Company and the Bank have been parties to that certain
Third Amended and Restated Loan Agreement dated as of November 1, 1996 (the "Old
Agreement"), under which the Bank made certain loans and advances to the Company
secured by all or substantially all of the Company's assets; and

         WHEREAS, the Company has requested additional financial accommodations,
and the Company and the Bank have agreed to amend and restate the terms and
conditions of the Old Agreement, as set forth hereinafter.

                                   Agreements

         In consideration of the Bank's making the following described loans,
the mutual covenants herein contained and other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged by each of the
parties hereto, the Company and the Bank agree as follows:

                i.        The $15,000,000 Revolving Line of Credit.

         (a)    Subject to, and upon the terms, conditions, covenants and
agreements contained herein, the Bank agrees to loan the Company, at any time,
and from time to time prior to the maturity of the Company's promissory note
executed in conjunction with this Agreement, such amounts as the Company may
request up to but not exceeding an aggregate principal sum at any time
outstanding equal to $15,000,000 (the "Revolving Line of Credit"); within such
limits and during such period, the Company may borrow, repay, and re-borrow
hereunder. All loans under the Revolving Line of Credit shall be evidenced by
the Company's Renewal Master Revolving Credit Note dated the date hereof (the
"Revolving Note"), in form and substance satisfactory to the Bank, payable to
the order of the Bank, and bearing interest upon the terms provided therein (but
in no event to exceed the maximum non-usurious interest rate permitted by law).
The principal of and interest on the Revolving Note shall be due and payable as
set forth on the face of the Revolving Note. Notation by the Bank on its records
shall constitute prima facie evidence of the amount and date of any payment or
borrowing thereunder. The Revolving Line of Credit shall be used by the Company
for its ordinary working capital needs, or for general corporate purposes, or
for its acquisition of all or substantially all of the assets or capital stock
of one or more operating businesses (each such acquisition a "Revolver
Acquisition").


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 1
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         (b)    Advances Related to Letters of Credit. Advances under the 
Revolving Line of Credit may also be made to fund Letters of Credit (as
hereinafter defined) that are issued under the Revolving Note and are drawn
upon, provided, the Bank may, in its own discretion, advance funds under the
Revolving Line of Credit to fund such Letters of Credit (as hereinafter defined)
when the Company does not reimburse the Bank for such funding. All such advances
shall be added to the principal amount of the Revolving Note and shall be
reimbursable to the Bank by the Company upon demand therefor.

                ii.         The $5,000,000 Acquisition Line of Credit. Subject 
                        to, and upon the terms, conditions, covenants and
                        agreements contained herein, at the Company's request
                        the Bank has agreed to loan the Company up to the sum of
                        $5,000,000 to be utilized by the Company solely for its
                        acquisition of all or substantially all of the assets or
                        capital stock of one or more operating businesses (each
                        an "Acquisition"); within such limits and until October
                        31, 1997 (but not thereafter), the Company may borrow,
                        repay and reborrow hereunder. Such loans (the
                        "Acquisition Indebtedness") are evidenced by the
                        Company's Acquisition Note dated November 1, 1996 (the
                        "Acquisition Note"), executed concurrently with the
                        execution of the Old Agreement, payable to the order of
                        the Bank, and bearing interest upon the terms provided
                        therein (but in no event to exceed the maximum
                        non-usurious interest rate permitted by law). The
                        Acquisition Indebtedness shall convert from a line of
                        credit to a term repayment on November 1, 1997 in
                        accordance with the terms of the Acquisition Note. The
                        principal of and interest on the Acquisition Note shall
                        be due and payable as set forth on the face of the
                        Acquisition Note. Notation by the Bank on its records
                        shall constitute prima facie evidence of the amount and
                        date of any payment or borrowing thereunder.

                iii.        Renewals and Extensions. All renewals, extensions,
                        modifications and rearrangements of the Revolving Note
                        and the Acquisition Note, if any, shall be deemed to be
                        made pursuant to this Agreement, and accordingly, shall
                        be subject to the terms and provisions hereof, and the
                        Company shall be deemed to have ratified, as of such
                        renewal, extension, modification or rearrangement date,
                        all of the representations, covenants and agreements
                        herein set forth.

                iv.         Old Agreement Superseded. This Agreement supersedes
                        and replaces the Old Agreement in its entirety;
                        provided, that the Company's liability to the Bank for
                        outstanding loans and other indebtedness under the Old
                        Agreement and its predecessors (the amount of which the
                        Company acknowledges is, as of August 28, 1997,
                        $8,934,300 under the Revolving Note and $5,000,000 under
                        the Acquisition Note), shall continue in full force and
                        effect under the terms hereof. The foregoing amounts of
                        indebtedness shall constitute the initial outstanding
                        principal amount under the Revolving Note and the
                        Acquisition Note, respectively.


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 2
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                v.          Letters of Credit. Subject to the conditions herein,
                        the Bank shall from time to time, at the request of the
                        Company, issue Letters of Credit (herein so called) to
                        Company's vendors for the acquisition of inventory for
                        the Company. The aggregate outstanding amount of any
                        Letters of Credit issued by Bank hereunder shall
                        constitute a portion of the Revolving Line of Credit,
                        and shall in no event exceed the sum of $2,000,000. The
                        fees for such issuance shall be in accordance with the
                        Bank's then existing fee schedule therefor. Such Letters
                        of Credit shall be considered in computing the amount of
                        funds available to the Company, as provided in Section 6
                        herein. The Bank shall not be obligated: (a) to issue
                        Letters of Credit if the issuance of same would cause
                        the Outstanding Credit (as hereinafter defined) to
                        exceed the Borrowing Base (as hereinafter defined); (b)
                        to issue such Letters of Credit with an expiration date
                        after the maturity date of the Revolving Note; and (c)
                        to extend the expiration date of such Letters of Credit
                        to a date after the maturity date of the Revolving Note.

                vi.         Availability Under Revolving Note.

                                (i)         Revolving Note. The aggregate 
                                        principal amount at any time outstanding
                                        under the Revolving Note and the 
                                        Acquisition Note, including without 
                                        limitation the face amount of all 
                                        outstanding Letters of Credit issued 
                                        for the account of the Company (said 
                                        principal amount collectively being 
                                        referred to herein as the "Outstanding 
                                        Credit") shall not at any time exceed 
                                        the Borrowing Base, as hereinafter 
                                        defined.

                                (ii)        Borrowing Base Compliance. In the 
                                        event the Outstanding Credit at any time
                                        exceeds the Borrowing Base, then the
                                        Company shall immediately make such
                                        payments to the Bank necessary to reduce
                                        the Outstanding Credit to an amount such
                                        that the Outstanding Credit is less than
                                        or equal to the amount of the Borrowing
                                        Base.

                  vii.          Borrowing Base.

         (a) The "Borrowing Base" shall be equal to an amount that is 5.50 times
the Free Cash Flow of the Company; calculated on a rolling, preceding 12-month
basis. The term "Free Cash Flow" means the Company's net income plus
depreciation and amortization, less any non- discretionary, maintenance capital
expenditures (which shall include, without limitation, all amounts spent for the
purchase and replacement of rental equipment). The Free Cash Flow, and all
components thereof, shall be computed by the Company and reported to the Bank in
accordance with generally accepted accounting principles, consistently applied
("GAAP").


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         (b)    For purposes of determining the Borrowing Base upon, or 
following, an Acquisition or a Revolver Acquisition by the Company, the Company
shall include in the calculation in Subsection 7(a) hereinabove the Free Cash
Flow for the division, corporation or other entity that is the subject of such
acquisition, to be computed by the Company and reported to the Bank in
accordance with GAAP, but without any adjustments for efficiencies that the
Company might realize in its operations after the acquisition.

         (c)    In the event that the Bank disputes the amount of the Borrowing
Base as calculated and reported by the Company, the Bank may, upon notice to the
Company, make any reasonable adjustment to the Borrowing Base for purposes of
determining availability under the Revolving Note and the Acquisition Note.

                viii.   Requests for Advances. Advances under the Revolving Line
                        of Credit may be made by telephonic oral request,
                        written request signed by an authorized officer of the
                        Company or by telephonic facsimile request, provided
                        that any such advance shall be deposited in an account
                        of the Company, unless such authority for telephonic
                        oral requests or telephonic facsimile requests is
                        revoked in writing by John P. Watson, as designated
                        agent of the Company (or such other designated agent as
                        the Bank approves in writing), and such revocation is
                        actually received by the Bank (the "Revocation"). Any
                        telephonic oral request shall be followed with a written
                        request for an advance in accordance with this Agreement
                        within twenty- four (24) hours. In consideration of the
                        Bank's permitting the Company to make telephonic oral
                        requests and telephonic facsimile requests for advances
                        under the Revolving Note until Revocation, the Company
                        covenants and agrees to assume liability for and to
                        protect, indemnify and hold the Bank harmless from any
                        and all liabilities, obligations, damages, penalties,
                        claims, causes of action, costs, charges and expenses,
                        including attorneys' fees and expenses of employees,
                        which may be imposed, incurred by or asserted against
                        the Bank (other than that caused by Bank's willful
                        misconduct) by reason of any loss, damage or claim
                        howsoever arising or incurred because of or out of or in
                        connection with (i) any action of the Bank pursuant to
                        telephonic oral requests and telephonic facsimile
                        requests for advances under the Revolving Line of
                        Credit, (ii) the breach of any provisions of this
                        Agreement by the Company, (iii) the transfer of funds
                        pursuant to such telephonic oral requests and telephonic
                        facsimile requests, or (iv) the Bank's honoring or
                        failing to honor any telephonic oral request or
                        telephonic facsimile request for any reason. The Bank is
                        entitled to rely upon and act upon telephonic oral
                        requests and telephonic facsimile requests made or
                        purportedly made by any of the officers or employees
                        specified in the resolutions delivered to the Bank of
                        even date herewith, as supplemented in writing from time
                        to time and accepted by the Bank, and the Company shall
                        be unconditionally and absolutely estopped from denying
                        (i) the authenticity and validity of any such
                        transaction so acted upon by the Bank once the Bank has
                        advanced funds under the Revolving Line of Credit and
                        deposited or


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                        transferred such funds as requested in any such
                        telephonic oral request or telephonic facsimile request,
                        and (ii) the Company's liability and responsibility
                        therefor.

                ix.         Prepayments. Any prepayment on the Revolving Note 
                        and the Acquisition Note (collectively, the "Notes")
                        shall be paid at the offices of the Bank. The Company
                        shall be entitled to prepay the Notes from time to time
                        and at any time, in whole or in part, without notice or
                        penalty except as set forth in the Notes. All
                        prepayments on the Notes shall be applied as set forth
                        in the Notes. No prepayment shall relieve the Company of
                        the obligation to pay the principal and interest on the
                        Notes until such time as all obligations are paid in
                        full.

                x.          Collateral for the Loans. The Outstanding Credit and
                        any and all other indebtedness of any kind whatsoever
                        now owing or hereafter arising under this Agreement
                        (which shall collectively be referred to herein as the
                        "Bank Indebtedness") shall be secured by the following
                        (hereinafter called the "Collateral"), as to which the
                        Company hereby grants to the Bank a security interest:

                                (i)         All accounts now owned or existing 
                                        as well as any and all that may 
                                        hereafter arise or be acquired by the 
                                        Company, and all proceeds and products 
                                        thereof, including without limitation, 
                                        all notes, drafts, acceptances, 
                                        instruments, general intangibles 
                                        (including tax refunds) 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; and all
                                        interests of the Company in any goods,
                                        the sale or lease of which shall have
                                        given rise to any of the foregoing;

                                (ii)        All of the Company's inventory,
                                        including goods, merchandise, raw
                                        materials, goods in process, and
                                        finished goods 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 the Company'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 whether now or hereafter in the
                                        possession of the Company, warehouseman,
                                        bailee or any other person;


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                                (iii)       All of the Company's equipment of
                                        every nature and description whatsoever
                                        now owned or hereafter acquired
                                        including all appurtenances and
                                        additions thereto and substitutions
                                        therefor, wheresoever located, including
                                        all tools, parts and accessories used in
                                        connection therewith;

                                (iv)        All of the Company's general 
                                        intangibles (including, without 
                                        limitation, the Company's service marks
                                        and trademarks) and other personal 
                                        property now owned or hereafter 
                                        acquired, including but not limited to 
                                        the Company's mailing lists; and

                                (v)         Such other property of the Company 
                                        as may be included within the definition
                                        of "Collateral" in the Amended and 
                                        Restated Commercial Security Agreement 
                                        dated as of March 1, 1996 (the "Security
                                        Agreement") executed by the Company in
                                        favor of the Bank.

                xi.         Execution of Loan Documents. The Company shall 
                        execute and deliver, or cause to be executed and 
                        delivered, to Bank the following described documents:

                                (i)         As a condition precedent to the
                                        effectiveness of this Agreement and the
                                        right of the Company to request any
                                        advance hereunder, the Company shall
                                        execute and deliver to the Bank the
                                        following documents and instruments (or
                                        shall obtain execution and delivery by
                                        any applicable third party), in form and
                                        substance satisfactory to the Bank:

                                        1)      This Agreement;

                                        2)      The Revolving Note;

                                        3)      Security agreements, financing
                                            statements, and all other documents
                                            or instruments described or 
                                            contemplated herein or otherwise 
                                            required by the Bank to secure the 
                                            payment of the Notes and the 
                                            performance by the Company of its
                                            obligations hereunder and thereunder
                                            (the "Security Instruments") 
                                            evidencing a first priority security
                                            interest in


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                                            favor of the Bank in all property of
                                            the Company;

                                        4)       The resolutions of
                                            
                                            the board of directors of the 
                                            general partner of the Company 
                                            approving the Company's execution
                                            and performance of this Agreement, 
                                            as certified by the general 
                                            partner's corporate secretary;

                                        5)      A Consent and Reaffirmation of
                                            Guarantors executed by BearCom, 
                                            Inc., Page- Com GP, Inc. and Bear 
                                            Communications, Inc., in form and
                                            substance satisfactory to the Bank, 
                                            reaffirming their respective 
                                            guarantees and the other documents
                                            and instruments executed and 
                                            delivered to the Bank in connection
                                            with the Old Agreement; and

                                        6)      The Company's attorneys shall 
                                            execute and deliver to the Bank, in
                                            form and substance satisfactory to
                                            the Bank, an opinion letter 
                                            supporting the validity and 
                                            enforceability of the Loan Documents
                                            (as defined hereinafter) and the 
                                            debt and liens evidenced thereby;

                                        7)      all other documents or 
                                            instruments requested by the Bank to
                                            be executed concurrently herewith.

                                (ii)        In connection with the Bank's 
                                        issuance of each Letter of Credit, the 
                                        Company shall, in addition to the 
                                        documents required in Section 11(a) 
                                        above, execute and deliver to the Bank 
                                        a Letter of Credit Application and 
                                        Agreement (herein so called), provided 
                                        the Bank shall have no obligation to 
                                        issue a Letter of Credit for the 
                                        account of the Company until a Letter 
                                        of Credit Application and Agreement has 
                                        been executed by the Company and 
                                        delivered to the Bank.

                xii.        Use of Proceeds. The proceeds of the Revolving Note
                        shall be used by the Company solely to provide for the
                        ordinary working capital needs of the Company, for
                        general corporate purposes or for Revolver Acquisitions.
                        The proceeds of the Acquisition Note shall be used by
                        the Company solely for Acquisitions. No part of the
                        proceeds received hereunder will be used,


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                        directly or indirectly, for the working capital needs of
                        any partner in, or affiliates of, the Company, nor for
                        the purpose of purchasing or carrying, or the payment in
                        full or in part, of indebtedness which was incurred for
                        the purposes of purchasing or carrying margin of stock,
                        as such term is defined in Section 221.3 of Regulation U
                        of the Board of Governors of the Federal Reserve System
                        12 C.F.R., Chapter II, Part 221.

                xiii.       Representations and Warranties. Until payment and
                        performance in full of the Notes, unless the Company
                        receives prior written approval of a deviation therefrom
                        from the Bank, the Company represents, warrants and
                        covenants that:

                                (i)         The Company is a limited partnership
                                        duly registered, validly existing and in
                                        good standing under the laws of the
                                        state of its registration and is duly
                                        licensed, qualified to do business and
                                        in good standing in each jurisdiction in
                                        which the ownership of its property or
                                        the conduct of its business requires
                                        such licensing and qualification and has
                                        all powers and all permits, consents and
                                        authorizations necessary to own and
                                        operate its properties and to carry on
                                        its business as presently conducted. The
                                        execution, delivery and performance of
                                        this Agreement by the Company, the
                                        borrowings hereunder and the execution
                                        and delivery of the Revolving Note, the
                                        Acquisition Note, the Security
                                        Instruments, the Letter of Credit
                                        Applications and Agreements, the
                                        Company's Amended and Restated
                                        Repurchase Agreement with Motorola, Inc.
                                        dated March 1, 1996 (the "Repurchase
                                        Agreement"), and the several agreements
                                        and instruments contemplated thereby,
                                        (i) have been duly authorized by proper
                                        partnership proceedings and (ii) will
                                        not contravene, or constitute a default
                                        under, any provision of applicable law
                                        or regulation or of the partnership
                                        agreement of the Company, or of any
                                        mortgage, indenture, contract, agreement
                                        or other instrument, or any judgment,
                                        order or decree, binding upon the
                                        Company. No consents of the Company's
                                        limited partner(s) or any holder of any
                                        indebtedness of the Company are required
                                        as a condition to the validity of this
                                        Agreement. This Agreement, the Notes,
                                        the Security Instruments, the Letter of
                                        Credit Applications and Agreements, the
                                        Repurchase Agreement and any agreements,
                                        documents and instruments contemplated
                                        herein and


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 8
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                                        thereby, or in any way related thereto 
                                        whether executed prior hereto, 
                                        simultaneously herewith or hereafter 
                                        (all of same being hereinafter sometimes
                                        called the "Loan Documents"), when duly 
                                        executed and delivered in accordance 
                                        with this Agreement, will constitute 
                                        legal, valid and binding obligations of 
                                        the Company in accordance with their 
                                        respective terms.

                                (ii)        The unaudited balance sheet of the
                                        Company at July 31, 1997, the related
                                        statement of income and retained
                                        earnings for the period then ended,
                                        copies of which have been delivered to
                                        the Bank, accurately represent the
                                        financial position of the Company at
                                        July 31, 1997 and the results of its
                                        operations for the periods then ended in
                                        conformity with GAAP applied on a basis
                                        consistent with the preceding year. No
                                        material adverse change has occurred
                                        since July 31, 1997 in the financial
                                        position or in the results of operations
                                        of the Company or in its business.

                                (iii)       No approvals or consents of any
                                        governmental department, administrative
                                        agency or instrumentality having
                                        jurisdiction over the Company are
                                        necessary to permit the Company to enter
                                        into the Loan Documents or to make any
                                        Acquisition or Revolver Acquisition,
                                        except as previously expressly disclosed
                                        to the Bank in writing before such
                                        Acquisition or Revolver Acquisition
                                        becomes effective.

                                (iv)        There is no action, suit or
                                        proceeding pending or, to the
                                        knowledge of the Company, threatened
                                        against the Company or the Collateral
                                        before any court, governmental
                                        department, administrative agency or
                                        instrumentality which, if such action,
                                        suit or proceeding were adversely
                                        determined, would adversely affect the
                                        financial position or the results of
                                        operations of the Company or its
                                        business or the ability of the Company
                                        to perform its obligations under the
                                        Loan Documents.

                                (v)         No Default or Event of Default
                                        (hereinafter defined) has occurred and
                                        is continuing.

                                (vi)        The Company has good and
                                        indefeasible title to all of its
                                        assets and properties, free and clear of
                                        all


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 9
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                                        security interests, mortgages, liens or
                                        encumbrances, except as otherwise
                                        permitted under this Agreement or
                                        reflected in the Company's financial
                                        statements submitted to the Bank and
                                        dated as of July 31, 1997.

                                (vii)       The Company is not an investment 
                                        company within the meaning of the 
                                        Investment Company Act of 1940.

                                (viii)      All United States tax returns and
                                        all required State and foreign tax
                                        returns relating to the Company have
                                        been filed by it or on its behalf and
                                        all taxes due thereunder have been paid,
                                        except such amounts which are the
                                        subject of a bona fide dispute which the
                                        Company is diligently pursuing in good
                                        faith. All other tax returns required to
                                        be filed by the Company or on the
                                        Company's behalf with any taxing
                                        jurisdiction have been filed and all tax
                                        liabilities shown thereon to be due have
                                        been paid and such returns properly
                                        reflect the taxes of the Company for the
                                        periods covered thereby.

                                (ix)        The security interests, mortgages
                                        and liens attaching to the Collateral 
                                        will at all times constitute valid, 
                                        perfected and enforceable first
                                        priority security interests, mortgages
                                        and liens in favor of the Bank, and the
                                        Collateral is and shall be at all times
                                        subject to no other security interests,
                                        mortgages, liens or encumbrances, except
                                        as otherwise permitted under this
                                        Agreement. Before any further funding
                                        under the Notes, the Company will have
                                        taken, or will have participated with
                                        the Bank in taking, all necessary action
                                        and will have made all necessary filings
                                        to provide the Bank with perfected,
                                        first priority (except as otherwise
                                        permitted under this Agreement) security
                                        interests, mortgages and liens in the
                                        Collateral under the laws of all
                                        appliable jurisidctions.

                xiv.        Affirmative Covenants. Until payment and performance
                        in full of the Notes, unless the Company receives prior
                        written approval of a deviation therefrom from the Bank,
                        the Company covenants and agrees to:

                                (i)         Annual Statements. Furnish the Bank,
                                        within one hundred (100) days after the
                                        end of the fiscal year of BearCom, Inc.,
                                        a copy of BearCom, Inc.'s


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 10
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                                        consolidated audited financial 
                                        statements (which shall include the 
                                        Company), consisting of at least a 
                                        balance sheet and related statement of 
                                        income, retained earnings and changes 
                                        in financial condition of BearCom, Inc. 
                                        and the Company prepared in conformity 
                                        with GAAP, applied on a basis consistent
                                        with that of the preceding year (if 
                                        applicable), and certified by an 
                                        independent certified public accountant 
                                        selected by BearCom, Inc. and 
                                        satisfactory to the Bank.

                                (ii)        Consolidating Statements. Furnish 
                                        the Bank, within one hundred (100) days
                                        after the end of the fiscal year of
                                        BearCom, Inc., a copy of its
                                        consolidating financial statements
                                        including all of BearCom, Inc.'s
                                        subsidiaries and affiliates, including
                                        without limitation, the Company.

                                (iii)       Monthly Statements. Furnish the Bank
                                        within thirty (30) days after the end of
                                        each calendar month during the term
                                        hereof, a copy of BearCom, Inc.'s
                                        consolidated unaudited financial
                                        statements for such calendar month,
                                        consisting of at least a balance sheet
                                        and related statement of income,
                                        retained earnings and a statement of
                                        cash flow of BearCom, Inc. and the
                                        Company, prepared in conformity with
                                        GAAP and certified by the chief
                                        financial officer of BearCom, Inc.

                                (iv)        Compliance Certificate. Furnish the 
                                        Bank concurrently with the delivery of 
                                        the financial statements required to be
                                        delivered pursuant to subsection (c)
                                        above, a Compliance Certificate in the
                                        form of the Compliance Certificate
                                        attached hereto as Exhibit A, signed by
                                        an authorized officer or agent of the
                                        Company.

                                (v)         Borrowing Base Certificate. Furnish 
                                        the Bank a Borrowing Base Certificate in
                                        the form of the Borrowing Base 
                                        Certificate attached hereto as Exhibit 
                                        B-1, signed by an authorized officer or 
                                        agent of the Company, not later than 
                                        thirty (30) days after the end of each 
                                        calendar month during the term hereof, 
                                        with regard to and as of the end of 
                                        such calendar month, in order to 
                                        evidence Borrowing Base compliance under


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 11
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                                        Section 5 hereof. Company will further 
                                        furnish the Bank with a Draw Request 
                                        Form in the form attached hereto as 
                                        Exhibit B-2 not later than 1:00 p.m. on 
                                        any business day on which the Company 
                                        is requesting an advance under the 
                                        Revolving Line of Credit.

                                (vi)        Accounts Receivable Listing and 
                                        Aging. Furnish the Bank a current 
                                        listing and aging of the Company's 
                                        accounts receivable within ten (10) days
                                        of a written request therefor by the 
                                        Bank, with aging of accounts receivable 
                                        on the basis of current, 30, 60, and 
                                        over 90 days from date of original 
                                        invoice.

                                (vii)       Accounts Payable Listing and Aging.
                                        Furnish the Bank a current listing and
                                        aging of the Company's accounts payable
                                        within ten (10) days from a written
                                        request therefor by the Bank, with aging
                                        of accounts payable on the basis of
                                        current, 30, 60, and over 90 days.

                                (viii)      Inventory Summaries. Furnish the
                                        Bank a current, detailed listing
                                        of inventory in form and detail
                                        acceptable to the Bank within ten (10)
                                        days of a written request therefor by
                                        the Bank.

                                (ix)        Insurance. Maintain, in amounts
                                        satisfactory to the Bank, liability,
                                        property, casualty and business
                                        interruption insurance with generally
                                        recognized reputable companies in the
                                        amounts and types and against the risks,
                                        liabilities and contingencies as is
                                        usually carried by a similar business in
                                        the same general area and of similar
                                        size to the Company, with the Bank named
                                        as loss payee as its interest may
                                        appear, such policies to be
                                        non-cancelable without thirty (30) days
                                        prior written notice to the Bank.

                                (x)         Taxes. Pay and discharge all taxes,
                                        assessments and governmental charges or
                                        levies imposed on the Company or on its
                                        income or profits or on any of its
                                        property prior to the date on which
                                        penalties or liens attached thereto and
                                        become of public record, except such
                                        amounts which are the subject of a bona
                                        fide dispute which the Company is
                                        diligently pursuing in good faith.


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 12
<PAGE>   13

                                (xi)        Litigation. Promptly give notice to
                                        the Bank of all litigation and all
                                        proceedings before governmental or
                                        regulatory agencies affecting the
                                        Company except litigation or proceedings
                                        not materially affecting the financial
                                        condition of the Company.

                                (xii)       Future Subsidiaries. Cause any
                                        corporation or entity which shall
                                        hereafter become a subsidiary of the
                                        Company to execute and deliver a
                                        guaranty of the Bank Indebtedness and
                                        such other documents and instruments as
                                        the Bank shall deem advisable or
                                        necessary.

                                (xiii)      Further Assurances. At any time and
                                        from time to time, execute and deliver 
                                        such further instruments and take such
                                        further action as may reasonably be
                                        requested by the Bank, in order to cure
                                        any defects in the execution and
                                        delivery of, or to comply with or
                                        accomplish the covenants and agreements
                                        contained in, the Loan Documents.

                                (xiv)       Liens. Subordinate any purchase 
                                        money liens to Bank by a Subordination
                                        Agreement in substance and form
                                        satisfactory to the Bank.

                                (xv)        Books and Records. Make available
                                        to the Bank the books and records
                                        of BearCom, Inc. and its subsidiaries
                                        and affiliates, including without
                                        limitation, the Company, including, but
                                        not limited to, the subsidiary journals,
                                        accounts receivable files, inventory
                                        records, general ledger, and
                                        correspondence files. Bank shall have
                                        the right to examine the Collateral at
                                        any reasonable time upon prior notice.

                                (xvi)       Existence. Continue to be a limited
                                        partnership duly registered and existing
                                        in good standing under the law of the
                                        jurisdiction under which it is
                                        registered and continue to be duly
                                        licensed or qualified as a foreign
                                        partnership in all jurisdictions wherein
                                        the character of the property owned or
                                        leased by it or the nature of the
                                        business transacted by it makes
                                        licensing or qualification necessary by
                                        a foreign partnership.


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 13
<PAGE>   14

                                (xvii)      Expenses. Pay reasonable expenses,
                                        including reasonable legal expenses and
                                        attorney's fees, of the Bank which have
                                        been or may be incurred by the Bank in
                                        connection with the preparation of
                                        future documentation deemed necessary by
                                        the Bank, the lending and incurring of
                                        obligations or liabilities hereunder,
                                        the collection of any note authorized
                                        hereby, or for the enforcement of any of
                                        the Company's obligations hereunder and
                                        under any document executed to secure
                                        the payment of any note authorized
                                        hereunder and for the recording and
                                        filing and recording and refiling of any
                                        such document.

                                (xviii)     Default. Give notice immediately 
                                        upon the knowledge or awareness of 
                                        senior management of the Company to Bank
                                        in writing of the occurrence of any
                                        Default.

                                (xix)       Name Change, Casualty. Give notice 
                                        of any change in the name of the 
                                        Company, any change in identity or the 
                                        Company's structure, and any uninsured 
                                        or partially uninsured loss through 
                                        fire, theft, liability or property 
                                        damage.

                                (xx)        Audits. The Company will permit
                                        Bank's Commercial Finance Department 
                                        to perform audits of the Company in 
                                        accordance with the Bank's internal 
                                        policies. The costs of all such annual 
                                        audits, up to an amount of $2,500
                                        per year, shall be borne by the Company.

                                (xxi)       Banking Relationship. As additional 
                                        Collateral, the Company will maintain 
                                        its primary depository relationship with
                                        the Bank.

                                (xxii)      Lock-box. As additional Collateral, 
                                        the Company will maintain its existing
                                        Lock-box arrangement for the benefit of
                                        the Bank.

                                (xxiii)     Unused Commitment Fee. The Company 
                                        will pay to the Bank, upon quarterly 
                                        invoice from the Bank, an unused 
                                        commitment fee equal to 0.25% of the 
                                        average daily unused balance of the 
                                        Revolving Line of Credit during the 
                                        preceding three (3) month period.


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 14
<PAGE>   15


                xv.         Negative Covenants. The Company covenants and agrees
                        that so long as the Notes are outstanding and unpaid,
                        without the written consent of the Bank, it shall not:

                                (i)         Debt. Create, incur, assume or 
                                        suffer to exist any debt, whether by way
                                        of loan, or the issuance or sale of 
                                        bonds, debentures, notes or securities,
                                        including deferred debt for the purchase
                                        price, leases, or otherwise, except (i)
                                        the loans described herein, (ii) current
                                        accounts payable and other current
                                        obligations (other than for borrowed
                                        money) arising out of transactions in
                                        the ordinary course of business, (iii)
                                        purchase money acquisitions or
                                        capitalized leases of fixed assets up to
                                        the amount of $500,000 in the aggregate;
                                        provided, that no such debt shall
                                        involve financial covenants on the part
                                        of the Company more restrictive than
                                        those contained in this Agreement, or
                                        (iv) a $300,000 note payable to Raycom,
                                        Inc. or its shareholders.

                                (ii)        Liabilities. Assume, guarantee,
                                        endorse, suffer to exist or otherwise
                                        become liable upon, or agree to purchase
                                        or otherwise furnish funds for the
                                        payment of, the obligations of any
                                        person, firm or corporation, except (i)
                                        for the obligations hereunder, and (ii)
                                        endorsement of negotiable instruments
                                        for deposit or collection or similar
                                        transactions in the ordinary course of
                                        business.

                                (iii)       Encumbrances. Create, incur, assume
                                        or suffer to exist any mortgage,
                                        deed of trust, pledge, encumbrance, lien
                                        or security interest of any kind, upon
                                        any of its property now owned or
                                        hereafter acquired, except (i) liens,
                                        mortgages, encumbrances or security
                                        interest to secure payment of the
                                        borrowings authorized hereunder; (ii)
                                        pledges or deposits to secure
                                        obligations under workmen's compensation
                                        laws or of similar legislation; (iii)
                                        deposits to secure public or statutory
                                        obligations, statutory mechanics',
                                        carriers', workmen's, repairmen's liens
                                        or other like items in the ordinary
                                        course of business in respect to
                                        obligations which are not overdue or are
                                        being contested in good faith; and (iv)
                                        existing liens not contemplated under
                                        this Agreement as reflected by the


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 15
<PAGE>   16




                                        financial statements submitted to the 
                                        Bank or disclosed in writing to Bank in
                                        connection with the execution of this
                                        Agreement.

                                (iv)        Acquisitions. Without prior written
                                        approval from the Bank, make any
                                        Acquisition or Revolving Acquisition or
                                        otherwise acquire the assets of another
                                        person or entity for consideration in
                                        excess of $500,000.

                                (v)         Subsidiaries. Form any new
                                        subsidiary or merge or invest in or
                                        consolidate with any corporation or
                                        other entity, or sell, lease, assign,
                                        transfer, or otherwise dispose of
                                        (whether in one transaction or as a
                                        series of related transactions) all or
                                        substantially all of its assets, whether
                                        now owned or hereafter acquired.

                                (vi)        Business. Without prior notice to 
                                        the Bank, change the nature of business
                                        conducted by the Company or engage in a
                                        kind of business different from that
                                        which the Company presently conducts.

                                (vii)       Distributions. Declare or pay any
                                        distribution (other than a distribution
                                        payable to partners in the amount of
                                        their liability for federal income taxes
                                        as a result of the Company's income) or
                                        make any other distribution on account
                                        of, or purchase, acquire, redeem or
                                        retire, any interest in the Company
                                        whether now or hereafter outstanding.

                                (viii)      Loans to Officers. Make any 
                                        additional loans or advances to partners
                                        or management of the Company, or to the
                                        officer or directors of any partner in
                                        the Company or of affiliate thereof,
                                        which in the aggregate exceed the sum of
                                        $100,000.

                                (ix)        Sale of Fixed Assets. Sell in excess
                                        of $250,000 in the aggregate, during 
                                        any fiscal year of the Company
                                        during the term hereof, of the Company's
                                        fixed assets, provided, however, with
                                        respect to those sales which in the
                                        aggregate are less than $250,000 for any
                                        fiscal year, the Company shall replace
                                        the assets sold with those of equal or
                                        greater value.


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 16
<PAGE>   17


                                (x)         Management. Make any change in the
                                        senior management of the Company which
                                        the Bank, in its sole discretion, deems
                                        significant; provided, however, that a
                                        breach of this covenant will not be an
                                        Event of Default unless the change in
                                        senior management of the Company is
                                        unsatisfactory to the Bank and the
                                        Company fails to make remedial changes
                                        to the senior management of the Company
                                        within thirty (30) days after notice
                                        thereof to the Company.

                                (xi)        Control. Make any change in the
                                        control of the Company which the
                                        Bank, in its sole discretion, deems
                                        significant.

                                (xii)       Pledges. Pledge any assets of
                                        Company without prior consent of
                                        the Bank, including, but not limited to,
                                        any purchase money liens not already
                                        disclosed to Bank.

                xvi.        Financial Covenants. The Company covenants and 
                        agrees that so long as the Notes are outstanding and 
                        unpaid, without the written consent of the Bank, the 
                        Company will:

                                (i)         Working Capital. Maintain minimum
                                        working capital of not less than
                                        $3,000,000. Working capital is defined
                                        as current assets less current
                                        liabilities, with the exception that
                                        current assets will exclude prepaid
                                        assets other than prepaid catalog
                                        expenses and current liabilities will
                                        include all of the outstanding Revolving
                                        Line of Credit.

                                (ii)        Structured Debt/Tangible Net Worth.
                                        Maintain a ratio of "Total Structured
                                        Indebtedness" to "Tangible Net Worth" of
                                        not greater than 2.0 to 1.0. "Total
                                        Structured Indebtedness" is defined as
                                        all obligations which would be
                                        classified on a balance sheet as debt
                                        for borrowed money (including, without
                                        limitation, all Bank Indebtedness) or
                                        debt for the deferred purchase price of
                                        property (including, without limitation,
                                        all capital lease obligations) in
                                        accordance with GAAP, but excluding
                                        trade payables, accrued liabilities or
                                        other operating liabilities. "Tangible
                                        Net Worth" is defined as the total
                                        assets of the Company, less the total
                                        liabilities of the Company


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 17
<PAGE>   18




                                        as set forth on its balance sheet at
                                        such date, plus indebtedness of
                                        the Company subordinated to the Bank,
                                        less contingent liabilities of the
                                        Company, except that the sum of the
                                        following shall be excluded from the
                                        determination of total assets: (i)
                                        goodwill, including any amounts (however
                                        designated on such balance sheet)
                                        representing the cost of acquisition of
                                        subsidiaries in excess of underlying
                                        tangible assets; (ii) patents,
                                        trademarks, copyrights, deferred charges
                                        (including, but not limited to,
                                        unamortized discount and expenses, but
                                        excluding prepaid expenses), intangible
                                        and other similar assets; (iii) advances
                                        to, and notes receivable from,
                                        stockholders, officers, employees and
                                        other related parties of the Company;
                                        (iv) the Company's mailing lists; and
                                        (v) other assets that are classified as
                                        "intangible" assets in accordance with
                                        GAAP.

                                (iii)       Minimum Quarterly Income. Maintain
                                        minimum net income, calculated in
                                        accordance with GAAP, of at least $1,000
                                        for each fiscal quarter of the Company.

                xvii.       Default. The Company shall be in default hereunder
                        if any one of the following events of default
                        ("Events of Default") shall occur and be continuing,
                        namely:

                                (i)         Default by the Company in the 
                                        payment of any sums owing to the Bank
                                        (including, without limitation, under
                                        the Revolving Note, Acquisition Note or
                                        other Bank Indebtedness); or

                                (ii)        Default by the Company in the
                                        payment of any sums owing to creditors 
                                        other than the Bank, or if the holder 
                                        of any such indebtedness declares or 
                                        may declare such indebtedness due
                                        prior to the stated maturity because of
                                        any default thereunder; provided, that
                                        such default shall involve at least the
                                        sum of $1,000 and shall have continued
                                        for a period of seven (7) days; or

                                (iii)       Any representation, statement,
                                        warranty or certificate made by the
                                        Company in the Loan Documents, or in any
                                        agreement, document or


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 18
<PAGE>   19

                                        instrument executed pursuant hereto or
                                        concurrently herewith, or hereafter
                                        furnished to the Bank in connection with
                                        any loan or loans hereunder, shall prove
                                        to have been incorrect in any material
                                        respect at the time of making or
                                        issuance thereof; or

                                (iv)        Default by the Company or any other
                                        party to the Loan Documents in the
                                        performance of any of the covenants or
                                        agreements set forth in the Loan
                                        Documents or in any other agreement,
                                        document or instrument executed pursuant
                                        hereto provided, however, that the
                                        provisions of this Agreement shall
                                        control in the event that any of such
                                        provisions are in conflict with the
                                        provisions of any other agreement,
                                        mortgage, indenture or instrument
                                        executed pursuant hereto and all of such
                                        provisions in such other instruments
                                        shall be deemed to be cumulative of the
                                        provisions hereof to the extent such
                                        provisions are not inconsistent
                                        herewith; or

                                (v)         The Company or any guarantor shall
                                        apply for or consent to, or acquiesce
                                        in the appointment of a receiver,
                                        trustee, or liquidator of itself or
                                        himself or of its or his property, or
                                        admit in writing its or his inability to
                                        pay its or his debts as they mature, or
                                        make a general assignment for the
                                        benefit of creditors or an Order of
                                        Relief be entered with respect to the
                                        Company by any court having competent
                                        jurisdiction in the premises, or file a
                                        voluntary petition in bankruptcy or a
                                        petition or answer seeking
                                        reorganization, composition,
                                        readjustment or arrangement, or similar
                                        relief with creditors, under any present
                                        or future statute, law or regulation, or
                                        otherwise, or take advantage of any
                                        insolvency law or file an answer
                                        admitting the material allegations of a
                                        petition filed against it or him in
                                        bankruptcy, reorganization, or
                                        insolvency proceedings, or corporate
                                        action shall be taken by it or him for
                                        the purpose of affecting any of the
                                        foregoing, or it or he shall have a
                                        receiver or trustee or assignee in
                                        bankruptcy or insolvency appointed for
                                        it or him, or its or his property,
                                        without its or his application or
                                        consent; or


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 19
<PAGE>   20




                                (vi)        Except for the contingent
                                        liabilities previously disclosed
                                        to the Bank or other contingent
                                        liabilities not contemplated by this
                                        Agreement which are incurred by the
                                        Company in the ordinary course of
                                        business, the Company becomes or remains
                                        liable, directly or indirectly, for or
                                        in connection with the obligations,
                                        stock or dividends of any other person
                                        or entity, whether by guaranty,
                                        endorsement, agreement to purchase or
                                        repurchase, agreement to lease,
                                        agreement to supply or advance funds
                                        (including, without limitation,
                                        agreements to maintain working capital,
                                        solvency or other balance sheet
                                        conditions or agreements to purchase
                                        stocks or make capital contributions),
                                        or otherwise;

                                (vii)       The Bank determines in the exercise
                                        of its judgment that the Company's
                                        financial condition has deteriorated,
                                        the prospect of repayment of the Bank
                                        Indebtedness is impaired or that the
                                        value of the Collateral has lessened
                                        materially;

                                (viii)      The Repurchase Agreement is
                                        terminated by a party thereto other
                                        than the Bank; or

                                (ix)        An event of default or Event of
                                        Default occurs under any guaranty
                                        executed in connection with this
                                        Agreement or the Old Agreement, or under
                                        any security agreement in favor of the
                                        Bank executed by any guarantor of
                                        Company's obligations to the Bank.

         Thereupon, in any such case, the obligation of the Bank to make any
advance or extend credit hereunder (including the issuance of Letters of Credit)
to or for the account of the Company pursuant hereto shall immediately terminate
and the Bank shall be entitled to each and every remedy and to take each and
every action permitted by the Loan Documents.

        xviii.      Reporting Procedures. The Company agrees from time to time
                to execute and deliver to the Bank such reasonable evidence of 
                the existence and identity of the Collateral and of its 
                availability as security pursuant hereto, as the Bank may
                reasonably request.

        xix.        Notice. All notices and other communications given to any
                party hereto, in accordance with the provisions of this
                Agreement, shall be deemed to have been given to any party when
                sent by registered or certified mail, if by mail, or when sent
                by telecopy, when and as reflected in the telecopy


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 20
<PAGE>   21




                confirmation, in each case addressed to the party as provided 
                herein, or in accordance with the latest unrevoked direction 
                from such party.

        xx.         Waiver. No failure to exercise and no delay in exercising on
                the part of the Bank of any right, power or privilege
                hereunder, shall operate as a waiver thereof; nor shall any
                single or partial exercise of any right, power or privilege
                hereunder, preclude any other or further exercise thereof, or
                the exercise of any other right, power or privilege. The rights
                and remedies herein provided are cumulative and not exclusive of
                any rights or remedies provided by law or in any other
                agreement.

        xxi.        Survival of Agreements. All agreements, representations and
                warranties herein made, shall survive the execution and delivery
                of the Revolving Note, the Acquisition Note, the Security
                Instruments and the other Loan Documents, and the making and
                renewal thereof.

        xxii.       Amendment. This Agreement may not be amended except in 
                writing signed by the Company and the Bank.

        xxiii.      Successors. This Agreement shall be binding upon and inure 
                to the benefit of the Company, the Bank and the successors and
                assigns of each party hereto.

        xxiv.       Severability. In the case any one or more of the provisions
                contained in the Loan Documents should be invalid, illegal, or
                unenforceable, in any respect, the validity, legality, and
                enforceability of the remaining provisions contained therein
                shall not in any way be affected thereby.

        xxv.        Interest. It is the intention of the parties hereto to
                comply with the laws of the State of Texas. Accordingly, it
                is agreed that, notwithstanding any provisions to the contrary
                in the Loan Documents, in no event shall said Loan Documents
                require the payment or permit the collection of interest, as
                defined under the laws of the State of Texas, in excess of the
                maximum amount permitted by such laws. If any such excess of
                interest is contracted for, charged or received, under the Loan
                Documents, or in the event the maturity of the indebtedness
                evidenced by the Notes is accelerated in whole or in part, or in
                the event that all or part of the principal or interest of the
                Notes shall be prepaid, so that under any of such circumstances
                the amount of interest contracted for, charged, or received
                under the Loan Documents on the amount of principal actually
                outstanding from time to time thereunder shall exceed the
                maximum amount of interest permitted by the laws of the State of
                Texas, then in any such event (a) the provisions of this section
                shall govern and control, (b) neither the Company nor any other
                person or entity now or hereafter liable for the payment of the
                Notes shall be obligated to pay the amount of such interest to
                the extent that it is in excess of the maximum


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 21
<PAGE>   22

                amount of interest permitted to be contracted for by, charged to
                or received from the party obligated thereon under the laws 
                of the State of Texas, (c) any such excess which may have
                been collected shall be either applied as a credit against the
                then unpaid principal amount on the Notes or refunded to the
                person paying the same, at the holder's option, and (d) the
                effective rate of interest shall be automatically reduced to the
                maximum lawful rate of interest permitted to be contracted for
                by, charged to or received from the party obligated thereon
                under the laws of the State of Texas as now or hereafter
                construed by the courts having jurisdiction thereof. It is
                further agreed that without limitation of the foregoing, all
                calculations of the rate of interest contracted for, charged or
                received under the Loan Documents, for the purpose of
                determining whether such rate exceeds the maximum lawful rate of
                interest, shall be made, to the extent permitted by the laws of
                the State of Texas, by amortizing, prorating, allocating and
                spreading in equal parts during the period of the full stated
                terms of the Notes all interest at any time contracted for,
                charged or received from the undersigned or otherwise by the
                holder or holders thereof in connection with such Notes.

        xxvi.       Participations, Etc. The Company expressly recognizes and
                agrees that the Bank may sell to other lenders participations
                in the loans incurred by the Company pursuant hereto and,
                therefore, as security for the due payment and performance of
                all indebtedness and other liabilities and obligations of the
                Company to the Bank under the Loan Documents and an other
                obligation of the Company to the Bank, whether now existing or
                hereafter arising, and to such lenders arising now by reason of
                such participations or otherwise, the Company hereby grants to
                the Bank and to such lenders, a lien on and security interest in
                any and all deposits or other sums at any time credited by or
                due from the Bank and such lenders or either or any of them to
                the Company, whether in regular or special depository accounts
                or otherwise, and any and all monies, securities and other
                property of the Company, and the proceeds thereof now or
                hereafter held or received by or in transit to the Bank and such
                lenders or either or any of them, from or for the Company
                whether for safekeeping, custody, pledge, transmission,
                collection or otherwise and any such deposit, sums, monies,
                securities and other property may at any time after Default be
                set-off, appropriated and applied by the Bank and by such
                lenders, or either or any of them, against any indebtedness,
                liabilities or other obligations, whether now existing or
                hereafter arising, of the Company or any of them, under this
                Agreement and the Notes, or otherwise whether or not such
                indebtedness, liabilities or other obligation is then due or
                secured by any indebtedness, liabilities or other obligation is
                then due or secured by any collateral or if it is so secured
                whether or not such collateral held by the Bank or such lenders
                is considered to be adequate.

        xxvii.      AGREEMENT FOR BINDING ARBITRATION. THE PARTIES AGREE TO BE 
                BOUND BY THE TERMS AND PROVISIONS OF THE ARBITRATION

FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 22
<PAGE>   23



                PROGRAM (DATED 9/23/94) WHICH IS ATTACHED HERETO AS EXHIBIT C
                AND INCORPORATED BY REFERENCE HEREIN AND IS ACKNOWLEDGED AS 
                RECEIVED BY THE PARTIES PURSUANT TO WHICH ANY AND ALL DISPUTES 
                SHALL BE RESOLVED BY MANDATORY BINDING ARBITRATION UPON THE 
                REQUEST OF ANY PARTY.

        xxviii.     Reaffirmation of Security Agreement. The Company hereby
                reaffirms in all respects the validity, effectiveness and
                enforceability of the Security Agreement, and agrees that the
                Bank Indebtedness hereunder shall constitute a part of the
                "obligations" thereunder for all purposes.

        xxix.       AMENDMENT, ASSUMPTION AND RESTATEMENT. THIS AGREEMENT
                CONSTITUTES AN AMENDMENT AND RESTATEMENT OF THAT CERTAIN THIRD
                AMENDED AND RESTATED LOAN AGREEMENT, DATED AS OF NOVEMBER 1,
                1996, BY AND BETWEEN THE COMPANY AND THE BANK.

        xxx.        NOTICE OF NO ORAL AGREEMENTS. THIS AGREEMENT AND THE OTHER
                LOAN DOCUMENTS CONSTITUTE A WRITTEN AGREEMENT WHICH REPRESENTS 
                THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE 
                CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT
                ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL 
                AGREEMENTS BETWEEN THE PARTIES RELATING TO THE LOANS.

         EXECUTED as of the day and year first above written.


                                     WELLS FARGO BANK (TEXAS), NATIONAL
                                     ASSOCIATION


                                     By:
                                          -------------------------------------
                                           Kristi Trout, Banking Officer


                                     BEARCOM OPERATING, L.P.

                                     By:
                                          -------------------------------------
                                     Printed Name:
                                                  ---------------------------
                                                    
                                                  --------of Page-Com GP., Inc.,
                                                  its general partner


FOURTH AMENDED AND RESTATED LOAN AGREEMENT - PAGE 23