<PAGE>   1
                                                                EXHIBIT 10.28(b)

                             BUSINESS LOAN AGREEMENT
<TABLE>
<CAPTION>

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  <S>              <C>             <C>           <C>         <C>          <C>               <C>             <C>            <C>
   PRINCIPAL       LOAN DATE        MATURITY     LOAN NO     CALL         COLLATERAL        ACCOUNT         OFFICER        INITIALS
  $350,000.00      2-24-1999       02-24-2002                CLTERM                                         JRF2Q
-----------------------------------------------------------------------------------------------------------------------------------
</TABLE>

REFERENCES IN THE SHADED AREA ARE FOR LENDER'S USE ONLY AND DO NOT LIMIT THE
APPLICABILITY OF THIS DOCUMENT TO ANY PARTICULAR LOAN OR ITEM.
<TABLE>
<CAPTION>

<S>               <C>                                         <C>               <C>
BORROWER:         BOBBY ALLISON WIRELESS, INC.                LENDER:           SOUTHTRUST BANK, NATIONAL ASSOCIATION
                  2056 LAKE AVENUE, S.E., SUITE A                               NORTH COUNTRYSIDE OFFICE
                  LARGO, FL 33771                                               28059 U.S. HWY 19 NORTH
                                                                                CLEARWATER, FL 33761

===================================================================================================================================
</TABLE>


THIS BUSINESS LOAN AGREEMENT BETWEEN BOBBY ALLISON WIRELESS, INC. ("BORROWER")
AND SOUTHTRUST BANK, NATIONAL ASSOCIATION ("LENDER") IS MADE AND EXECUTED ON THE
FOLLOWING TERMS AND CONDITIONS. BORROWER HAS RECEIVED PRIOR COMMERCIAL LOANS
FROM LENDER OR HAS APPLIED TO LENDER FOR A COMMERCIAL LOAN OR LOANS AND OTHER
FINANCIAL ACCOMMODATIONS, INCLUDING THOSE WHICH MAY BE DESCRIBED ON ANY EXHIBIT
OR SCHEDULE ATTACHED TO THIS AGREEMENT. ALL SUCH LOANS AND FINANCIAL
ACCOMMODATIONS, TOGETHER WITH ALL FUTURE LOANS AND FINANCIAL ACCOMMODATIONS FROM
LENDER TO BORROWER, ARE REFERRED TO IN THIS AGREEMENT INDIVIDUALLY AS THE "LOAN"
AND COLLECTIVELY AS THE "LOANS." BORROWER UNDERSTANDS AND AGREES THAT: (A) IN
GRANTING, RENEWING, OR EXTENDING ANY LOAN, LENDER IS RELYING UPON BORROWER'S
REPRESENTATIONS, WARRANTIES, AND AGREEMENTS, AS SET FORTH IN THIS AGREEMENT; (B)
THE GRANTING, RENEWING, OR EXTENDING OF ANY LOAN BY LENDER AT ALL TIMES SHALL BE
SUBJECT TO LENDER'S SOLE JUDGMENT AND DISCRETION; AND (C) ALL SUCH LOANS SHALL
BE AND SHALL REMAIN SUBJECT TO THE FOLLOWING TERMS AND CONDITIONS OF THIS
AGREEMENT.

TERM. This Agreement shall be effective as of February 24, 1999, and shall
continue thereafter until all Indebtedness of Borrower to Lender has been
performed In full and the parties terminate this Agreement in writing.

CONDITIONS PRECEDENT TO EACH ADVANCE. Lender's obligation to make the initial
Loan Advance and each subsequent Loan Advance under this Agreement shall be
subject to the fulfillment to Lender's satisfaction of all of the conditions set
forth In this Agreement and in the Related Documents.

         LOAN DOCUMENT. Borrower shall provide to Lender in form satisfactory to
         Lender the following documents for the Loan: (a) the Note, (b) Security
         Agreements granting to Lender security Interests In the Collateral, (c)
         Financing Statements perfecting Lenders Security Interests; (d)
         evidence of insurance as required below; and (e) any other documents
         required under this Agreement or by Lender or its counsel, including
         without limitation any guaranties described below.

         BORROWER'S AUTHORIZATION. Borrower shall have provided In form and
         substance satisfactory to Lender property certified resolutions, duly
         authorizing the execution and delivery of this Agreement, the Note and
         the Related Documents, and such other authorizations and other
         documents and instruments as Lender or its counsel, in their sole
         discretion, may require.

         PAYMENT OF FEES AND EXPENSES. Borrower shall have paid to Lender all
         fees, charges, and other expenses which are then due and payable as
         specified in this Agreement or any Related Document.

         REPRESENTATIONS AND WARRANTIES. The representations and warranties set
         forth in this Agreement, in the Related Documents, and in any document
         or certificate delivered to Lender under this Agreement are true and
         correct.

         NO EVENT OF DEFAULT. There shall not exist at the time of any advance a
condition which would constitute an Event of Default under this Agreement.

REPRESENTATIONS AND WARRANTIES. Borrower represents and warrants to Lender, as
of the date of this Agreement, as of the date of each disbursement of Loan
proceeds, as of the date of any renewal, extension or modification of any Loan,
and at all times any Indebtedness exists:

         ORGANIZATION. Borrower is a corporation which Is duly organized,
         validly existing, and in good standing under the laws of the State of
         Florida and is validly existing and in good standing in all states in
         which Borrower is doing business. Borrower has the full power and
         authority to own its properties and to transact the businesses in which
         It is presently engaged or presently proposes to engage. Borrower also
         is duly qualified as a foreign corporation and is in good standing in
         all states in which the failure to so quality would have a material
         adverse effect on its businesses or financial condition.

         AUTHORIZATION. The execution, delivery, and performance of this
         Agreement by Borrower, to the extent to be executed, delivered or
         performed by Borrower, have been duly authorized by all necessary
         action by Borrower; do not require the consent or approval of any other
         person, regulatory authority or governmental body; and do not conflict
         with, result In a violation of, or constitute a default under (a) any
         provision of its articles of incorporation or organization, or bylaws,
<PAGE>   2
         or any agreement or other instrument binding upon Borrower or (b) any
         law, governmental regulation, court decree, or order applicable to
         Borrower.

         FINANCIAL INFORMATION. Each financial statement of Borrower supplied to
         Lender truly and completely disclosed Borrower's financial condition as
         of the date of the statement, and there has been no material adverse
         change in Borrower's financial condition subsequent to the date of the
         most recent financial statement supplied to Lender. Borrower has no
         material contingent obligations except as disclosed in such financial
         statements.

         LEGAL EFFECT. This Agreement constitutes, and any instrument or
         agreement required hereunder to be given by Borrower when delivered
         will constitute, legal, valid and binding obligations of Borrower
         enforceable against Borrower in accordance with their respective terms.

         PROPERTIES. Except as contemplated by this Agreement or as previously
         disclosed in Borrower's financial statements or in writing to Lender
         and as accepted by Lender, and except for property tax liens for taxes
         not presently due and payable, Borrower owns and has good title to all
         of Borrower's properties free and clear of all liens and security
         Interests, and has not executed any security documents or financing
         statements relating to such properties. All of Borrower's properties
         are titled In Borrower's legal name, and Borrower has not used, or
         filed a financing statement under, any other name for at least the last
         five (5) years.

         HAZARDOUS SUBSTANCES. Except as disclosed to Lender in writing, no
         property of Borrower ever has been, or ever will be so long as this
         Agreement remains in effect, used for the generation, manufacture,
         storage, treatment, disposal, release or threatened release of any
         hazardous waste or substance, as those terms are defined in the
         "CERCLA," "SARA," applicable state or Federal laws, or regulations
         adopted pursuant to any of the foregoing. The representations and
         warranties contained herein are based on Borrower's due diligence in
         Investigating the properties for hazardous waste and hazardous
         substances. Borrower hereby (a) releases and waives any future claims
         against Lender for indemnity or contribution in the event Borrower
         becomes liable for cleanup or other costs under any such laws, and (b)
         agrees to indemnity and hold harmless Lender against any and all claims
         and losses resulting from a breach of this provision of this Agreement.
         This obligation to indemnity shall survive the payment of the
         Indebtedness and the satisfaction of this Agreement.

         COMMERCIAL PURPOSES. Borrower intends to use the Loan proceeds solely
         for business or commercial related purposes.

AFFIRMATIVE COVENANTS. Borrower covenants and agrees with Lender that, while
this Agreement is in effect, Borrower will:

         LITIGATION. Promptly inform Lender in writing of (a) all material
         adverse changes in Borrower's financial condition, and (b) all existing
         and all threatened litigation, claims, investigations, administrative
         proceedings or similar actions affecting Borrower or any guarantor of
         the Loan which could materially affect the financial condition of
         Borrower or the financial condition of any guarantor of the Loan.

         FINANCIAL RECORDS. Maintain its books and records In accordance with
         accounting principles acceptable to Lender, applied on a consistent
         basis, and permit Lender to examine and audit Borrower's books and
         records at all reasonable times.

         FINANCIAL STATEMENTS. Furnish Lender with, as soon as available, but in
         no event later than one hundred twenty (120) days after the end of each
         fiscal year, Borrower's balance sheet and income statement for the year
         ended, prepared by Borrower, and, as soon as available, but in no event
         later than thirty (30) days after the end of each fiscal quarter,
         Borrower's balance sheet and profit and loss statement for the period
         ended, prepared and certified as correct to the best knowledge and
         belief by Borrower's chief financial officer or other officer or person
         acceptable to Lender. All financial reports required to be provided
         under this Agreement shall be prepared in accordance with accounting
         principles acceptable to Lender, applied on a consistent basis, and
         certified by Borrower as being true and correct.

         ADDITIONAL INFORMATION. Furnish such additional information and
         statements, lists of assets and liabilities, agings of receivables and
         payables, inventory schedules, budgets, forecasts, tax returns, and
         other reports with respect to Borrower's financial condition and
         business operations as Lender may request from time to time.



<PAGE>   3

===============================================================================

             2-24-1999      BUSINESS LOAN AGREEMENT         PAGE 2
                                   (CONTINUED)


         FINANCIAL COVENANTS AND RATIOS. Comply with the following covenants and
         ratios:

         For purposes of this Agreement and to the extent the following terms
         are utilized In this Agreement, the term "Tangible Net Worth" shall
         mean Borrower's total assets excluding all Intangible assets (i.e.,
         goodwill, trademarks, patents, copyrights, organizational expenses, and
         similar intangible items, but including leaseholds and leasehold
         Improvements) less total Debt. The term "Debt shall mean all of
         Borrower's liabilities excluding Subordinated Debt. The term
         "Subordinated Debt shall mean indebtedness and liabilities of Borrower
         which have been subordinated by written agreement to Indebtedness owed
         by Borrower to Lender In form and substance acceptable to Lender. The
         term "Working Capital" shall mean Borrower's current assets, excluding
         prepaid expenses, less Borrower's current liabilities. The term "Liquid
         Assets" shall mean Borrower's cash on hand plus Borrower's readily
         marketable securities. The term "Cash Flow" shall mean net Income after
         taxes, and exclusive of extraordinary gains and Income, plus
         depreciation and amortization. Except as provided above, all
         computations made to determine compliance with the requirements
         contained in this paragraph shall be made in accordance with accounting
         principles acceptable to Lender, applied on a consistent basis, and
         certified by Borrower as being true and correct.

         GUARANTIES. Prior to disbursement of any Loan proceeds, furnish
         executed guaranties of the Loans in favor of Lender, executed by the
         guarantors named below, on Lender's forms, and in the amounts and under
         the conditions spelled out In those guaranties.

<TABLE>
<CAPTION>

          GUARANTORS                                         AMOUNTS
          ----------                                         -------
          <S>                                                <C>
          JAMES L. RALPH                                     UNLIMITED
          STERNE, AGEE & LEACH GROUP, INC.                          34%
          ROBERT L. MCGINNIS                                 UNLIMITED
</TABLE>

         LOAN PROCEEDS. Use all Loan proceeds solely for Borrower's business
         operations, unless specifically consented to the contrary by Lender in
         writing.

         PERFORMANCE. Perform and comply with all terms, conditions, and
         provisions set forth in this Agreement and In the Related Documents in
         a timely manner, and promptly notify Lender if Borrower learns of the
         occurrence of any event which constitutes an Event of Default under
         this Agreement or under any of the Related Documents.

         OPERATIONS. Maintain executive and management personnel with
         substantially the same qualifications and experience as the present
         executive and management personnel; provide written notice to Lender of
         any change in executive and management personnel; conduct its business
         affairs in a reasonable and prudent manner and In compliance with all
         applicable federal, state and municipal laws, ordinances, rules and
         regulations respecting Its properties, charters, businesses and
         operations, Including without limitation, compliance with the Americans
         With Disabilities Act and with all minimum funding standards and other
         requirements of ERISA and other laws applicable to Borrower's employee
         benefit plans.

         INSPECTION. Permit employees or agents of Lender at any reasonable time
         to Inspect any and all Collateral for the Loan or Loans and Borrower's
         other properties and to examine or audit Borrower's books, accounts,
         and records and to make copies and memoranda of Borrower's books,
         accounts, and records. If Borrower now or at any time hereafter
         maintains any records (including without limitation computer generated
         records and computer software programs for the generation of such
         records) In the possession of a third party, Borrower, upon request of
         Lender, shall notify such party to permit Lender free access to such
         records at all reasonable times and to provide Lender with copies of
         any records it may request, all at Borrower's expense.

NEGATIVE COVENANTS. Borrower covenants and agrees with Lender that while this
Agreement is in effect, Borrower shall not, without the prior written consent of
Lender:

         INDEBTEDNESS AND LIENS. (a) Except for trade debt incurred in the
         normal course of business and indebtedness to Lender contemplated by
         this Agreement, create, incur or assume indebtedness for borrowed
         money, including capital leases, (b) except as allowed as a Permitted
         Lien, sell, transfer, mortgage, assign, pledge, lease, grant a security
         interest in, or encumber any of Borrower's assets, or (c) sell with
         recourse any of Borrower's accounts, except to Lender.

         CONTINUITY OF OPERATIONS. (a) Engage in any business activities
         substantially different than those in which Borrower is presently
         engaged, (b) cease operations, liquidate, merge, transfer, acquire or
         consolidate with any other entity, change ownership, change its name,
         dissolve or transfer or sell Collateral out of the ordinary course of
<PAGE>   4
         dissolve or transfer or sell Collateral out of the ordinary course of
         business, (c) pay any dividends on Borrower's stock (other than
         dividends payable in its stock), provided, however that notwithstanding
         the foregoing, but only so long as no Event of Default has occurred and
         Is continuing or would result from the payment of dividends, if
         Borrower is a *Subchapter S Corporation" (as defined in the internal
         Revenue Code of 1986, as amended), Borrower may pay cash dividends on
         its stock to its shareholders from time to time In amounts necessary to
         enable the shareholders to pay income taxes and make estimated Income
         tax payments to satisfy their liabilities under federal and state law
         which arise solely from their status as Shareholders of a Subchapter S
         Corporation because of their ownership of shares of stock of Borrower,
         or (d) purchase or retire any of Borrower's outstanding shares or alter
         or amend Borrower's capital structure.

         LOANS, ACQUISITIONS AND GUARANTIES. (a) Loan, invest in or advance
         money or assets, (b) purchase, create or acquire any interest in any
         other enterprise or entity, or (c) incur any obligation as surety or
         guarantor other than in the ordinary course of business.

CESSATION OF ADVANCES. If Lender has made any commitment to make any Loan to
Borrower, whether under this Agreement or under any other agreement, Lender
shall have no obligation to make Loan advances or to disburse Loan proceeds if:
(a) Borrower or any guarantor Is in default under the terms of this Agreement or
any other agreement that Borrower or any guarantor has with Lender; (b) Borrower
or any Guarantor becomes insolvent, files a petition In bankruptcy or similar
proceedings, or is adjudged a bankrupt; (c) there occurs a material adverse
change in Borrower's financial condition, in the financial condition of any
guarantor, or in the value of any collateral securing any Loan; (d) any
guarantor seeks, claims or otherwise attempts to limit, modify or revoke such
guarantor's guaranty of the Loan or any other loan with Lender; or (e) Lender in
good faith deems itself insecure, even though no Event of Default shall have
occurred.

RIGHT OF SETOFF. Borrower grants to Lender a contractual security interest in,
and hereby assigns, convoys, delivers, pledges, and transfers to Lender all
Borrower's right, title and interest in and to, Borrower's accounts with Lender
(whether checking, savings, or some other account), including without limitation
all accounts held jointly with someone else and all accounts Borrower may open
in the future, excluding however all IRA and Keogh accounts, and all trust
accounts for which the grant of a security interest would be prohibited by law.
Borrower authorizes Lender, to the extent permitted by applicable law, to charge
or setoff all sums owing on the indebtedness against any and all such accounts,
and, at Lender's option, to administratively freeze all such accounts to allow
Lender to protect Lender's charge and setoff rights provided on this paragraph.

EVENTS OF DEFAULT. Each of the following shall constitute an event of default
("Event of Default") under this Agreement:

         DEFAULT ON INDEBTEDNESS. Failure of Borrower to make any payment when
         due on the Loans.

         OTHER DEFAULTS. Failure of Borrower to comply with or to perform when
         due any other term, obligation, covenant or condition contained in this
         Agreement

         DEFAULT IN FAVOR OF THIRD PARTIES. Should Borrower default under any
         loan, extension of credit, security agreement, purchase or sales
         agreement, or any other agreement, in favor of any other creditor or
         person that may materially affect any of Borrower's property or
         Borrower's ability to repay the Loans or perform Borrower's obligations
         under this Agreement or any related document.

         FALSE STATEMENTS. Any warranty, representation or statement made or
         furnished to Lender by or on behalf of Borrower is false or misleading
         in any material respect at the time made or furnished, or becomes false
         or misleading at any time thereafter.

         INSOLVENCY. The dissolution or termination of Borrower's existence as a
         going business, the insolvency of Borrower, the appointment of a
         receiver for any part of Borrower's property, any assignment for the
         benefit of creditors, any type of creditor workout, or the commencement
         of any proceeding under any bankruptcy or insolvency laws by or against
         Borrower.

         CREDITOR OR FORFEITURE PROCEEDINGS. Commencement of foreclosure or
         forfeiture proceedings, whether by judicial proceeding, self-help,
         repossession or any other method, by any creditor of Borrower, any
         creditor of any grantor of collateral for the Loan this includes a
         garnishment, attachment, or levy



                                       2
<PAGE>   5



                2-24-1999      BUSINESS LOAN AGREEMENT     PAGE 3
                                   (CONTINUED)

================================================================================


         on or of any of Borrower's deposit accounts with Lender.

         EVENTS AFFECTING GUARANTOR. Any of the preceding events occurs with
         respect to any Guarantor of any of the Indebtedness or any Guarantor
         dies or becomes incompetent, or revokes or disputes the validity of, or
         liability under, any Guaranty of the Indebtedness. Lender, at its
         option, may, but shall not be required to, permit the Guarantor's
         estate to assume unconditionally the obligations arising under the
         guaranty in a manner satisfactory to Lender, and, in doing so, cure the
         Event of Default.

         CHANGE IN OWNERSHIP. Any change in ownership of twenty-five percent
         (25%) or more of the common stock of Borrower.

         ADVERSE CHANGE. A material adverse change occurs in Borrower's
         financial condition, or Lender believes the prospect of payment or
         performance of the Indebtedness is impaired.

         INSECURITY. Lender, in good faith, deems itself insecure.

EFFECT OF AN EVENT OF DEFAULT. If any Event of Default shall occur, except where
otherwise provided In this Agreement or the Related Documents, all commitments
and obligations of Lender under this Agreement Immediately will terminate and,
at Lender's option, all Indebtedness Immediately will become due and payable,
all without notice of any kind to Borrower, except that In the case of an Event
of Default of the type described In the "Insolvency" subsection above, such
acceleration shall be automatic and not optional. In addition, Lender shall have
all the rights and remedies provided In the Related Documents or available at
law, in equity, or otherwise. Except as may be prohibited by applicable law, all
of Lender's rights and remedies shall be cumulative and may be exercised
singularly or concurrently. Election by Lender to pursue any remedy shall not
exclude pursuit of any other remedy, and an election to make expenditures or to
take action to perform an obligation of Borrower or of any Grantor shall not
affect Lender's right to declare a default and to exercise its rights and
remedies.


BORROWER ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS BUSINESS LOAN
AGREEMENT, AND BORROWER AGREES TO ITS TERMS. THIS AGREEMENT IS DATED AS OF
FEBRUARY 24, 1999.

BORROWER:

BY:/s/ Robert L. McGinnis            (SEAL)
   ----------------------------------
     ROBERT L. MCGINNIS, CEO

LENDER:
SOUTHTRUST BANK, NATIONAL ASSOCIATION

BY: /s/ James A. Ray
   ----------------------------------
     AUTHORIZED OFFICER

================================================================================
LASER PRO, REG. U.S. PAT. & T.M.



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