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                                                                   EXHIBIT 10.28

                            BUSINESS LOAN AGREEMENT


This Business Loan Agreement (this "Agreement") is entered into as of the date
set forth below between Union Bank of California, N.A. ("Bank") and the
undersigned ("Borrower") with respect to each and every extension of credit
(whether one or more, collectively referred to as the "Loan") from Bank to
Borrower. In consideration of the Loan, Bank and Borrower agree to the following
terms and conditions:

1.  THE LOAN.

  1.1  The Note.  The Loan is evidenced by one or more promissory notes or other
  evidences of indebtedness, including each amendment, extension, renewal or
  replacement thereof, which are incorporated herein by this reference (whether
  one or more, collectively referred to as the "Note").

  *  Wherever "N/A" appears in a blank in this Agreement, it means the
  Subsection in which it appears is deemed deleted from this Agreement.

  1.2  Revolving Loan Clean-up Period.  For any portion of the Loan which is a
  revolving loan, at least 30 consecutive days during each 12 month period the
  principal amount outstanding under such revolving loan must be zero.

  1.3  Term Loan Availability Period.  For any portion of the Loan which is a
  term loan, loan proceeds shall be available for disbursement from October 15,
  1996 through March 31,1997 only.

  1.4  Fee. Borrower shall pay to bank a fee of $ 2,500.00.

  1.5  Collateral. The payment and performance of all obligations of Borrower
  under the Loan Documents is and shall be during the term of the Loan secured
  by a perfected security interest in such real or personal property collateral
  as is required by Bank and each security interest shall rank in first priority
  unless otherwise specified in writing by Bank.

  1.6  Guaranty. The payment and performance of all obligations of Borrower
  under the Loan Documents are and shall be during the term of the Loan
  guaranteed by: NA

  1.7  Subordination. Certain other obligations of Borrower are and shall be
  during the term of the Loan subordinated, to the repayment of the Loan and all
  other obligations of Borrower to Bank, pursuant to one or more subordination
  agreement(s) in favor of Bank executed and delivered by: NA

2.   CONDITIONS TO AVAILABILITY OF THE LOAN. Before Bank is obligated to
disburse all or any portion of the Loan, Bank must have received (a) the Note
and every other document required by Bank in connection with the Loan, each of
which must be in form and substance satisfactory to Bank (together with this
Agreement, referred to as the "Loan Documents"), (b) confirmation of the
perfection of its security interest in any collateral for the Loan, and (c)
payment of any fee required in connection with the Loan.

3.   REPRESENTATIONS AND WARRANTIES. Borrower represents and warrants (and each
request for a disbursement of the proceeds of the Loan shall be deemed a
representation and warranty made on the date of such request) that:

  3.1  Borrower is an individual or Borrower is duly organized and existing
  under the laws of the state of its organization and is duly qualified to
  conduct business in each jurisdiction in which its business is conducted;

  3.2  The execution, delivery and performance of the Loan Documents executed by
  Borrower are within Borrower's power, have been duly authorized, are legal,
  valid and binding obligations of  Borrower, and are 
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  not in conflict with the terms of any charter, bylaw, or other organization
  papers of Borrower or with any law, indenture, agreement or undertaking to
  which Borrower is a party or by which Borrower is bound or affected;

  3.3   All financial statements and other financial information submitted by
  Borrower to Bank are true and correct in all material respects, and there has
  been no material adverse change in Borrower's financial condition since the
  date of the latest of such financial statements;

  3.4   Borrower is properly licensed and in good standing in each state in
  which Borrower is doing business, and Borrower has complied with all laws and
  regulations affecting Borrower, including without limitation, each applicable
  fictitious business name statute;

  3.5  There is no event which is, or with notice or lapse of time or both would
  be, an Event of Default (as defined in Article 5);

  3.6   Borrower is not engaged in the business of extending credit for the
  purpose of, and no part of the Loan will be used, directly or indirectly, for
  purchasing or carrying margin stock within the meaning of Federal Reserve
  Board Regulation U; and

  3.7   Borrower is not aware of any fact, occurrence or circumstance which
  Borrower has not disclosed to Bank in writing which has, or could reasonably
  be expected to have, a material adverse effect on Borrower's ability to repay
  the Loan or perform its obligations under the Loan Documents.

4.  COVENANTS.  Borrower agrees, so long as the Loan or any commitment to make
any advance under the Loan is outstanding and until full and final payment of
all sums outstanding under any Loan Document, that Borrower will:

  4.1   Maintain:

      (a) Working Capital equal to at least $ NA As used herein, "Working
      Capital" means the excess of current assets over current liabilities);

      (b) A ratio of current assets to current liabilities of at least 2.00:
      1.00;

      (c) A quick ratio of cash, accounts receivable and marketable securities
      to current liabilities of at least NA: 1.00;

      (d) Tangible Net Worth of at least $ 6,500,000 (As used herein "Tangible
      Net Worth" means net worth increased by indebtedness of Borrower
      subordinated to Bank and decreased by patents, licenses, trademarks, trade
      names, goodwill and other similar intangible assets, organizational
      expenses, and monies due from affiliates including officers, shareholders
      and directors);

      (e) A ratio of total liabilities to Tangible Net Worth of not greater than
      NA: 1.00 (As used herein "Tangible Net Worth" means net worth increased by
      indebtedness of Borrower subordinated to Bank and decreased by patents,
      licenses, trademarks, trade names, goodwill and other similar intangible
      assets, organizational expenses, and monies due from affiliates including
      officers, shareholders and directors);

      (f) A profit after taxes of not less than $ NA, to be measured as of the
      end of each fiscal of Borrower for the period immediately preceding the
      date of measurement;

      (g) A ratio of Cash Flow to Debt Service of 2.00: 1.00. Compliance with
      this subsection to be measured as of the end of each fiscal year of
      Borrower.  (As used herein, "Debt Service" means that portion of long-term
      liabilities and capital leases coming due within 12 months of the date of
      calculation, and "Cash Flow" means net profit after taxes, to which
      depreciation, amortization and other non-cash expenses are added for the
      12 month period immediately preceding the date of calculation); and
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      (h) All accounting terms used in this Agreement shall have the definitions
      given them by generally accepted accounting principles, unless otherwise
      defined herein.

  4.2  Give written notice to Bank within 15 days of the following:

      (a) Any litigation or arbitration proceeding affecting Borrower where the
      amount in controversy is $ 100,000 or more;

      (b)  Any material dispute which may exist between Borrower and any
      government regulatory body or law enforcement body;

      (c) Any Event of Default or any event which, upon notice, or lapse of
      time, or both, would become an Event of Default;

      (d) Any other matter which has resulted or is likely to result in a
      material adverse change in Borrower's financial condition or operation;
      and

      (e)  Any change in Borrower's name or the location of Borrower's principal
      place of business, or the location of any collateral for the Loan, or the
      establishment of any new place of business or the discontinuance of any
      existing place of business.

  4.3  Furnish to Bank an income statement, balance sheet, and statement of
  retained earnings, with supportive schedules ("Financial Statement"), and any
  other financial information requested by Bank, prepared in accordance with
  generally accepted accounting principles and in a form satisfactory to Bank as
  follows:

      (a) Within 60 days after the close of each Quarter except for the final
      quarter of each fiscal year, Borrower's Form 10Q as of the close of such
      period.

      (b)  Within 120 days after the close of each fiscal year, a copy of
      Borrower's annual Financial Statement prepared by a Certified Public
      Account on an Audited basis.  Any independent certified public accountant
      who prepares Borrower's Financial Statement shall be selected by Borrower
      and reasonably satisfactory to Bank;

      (c) Within NA days after the close of each fiscal year, a copy of each
      guarantor's annual Financial Statement;

      (d) If any portion of the Loan is a Borrowing Base Loan, within NA days
      after each calendar month end, a copy of Borrower's monthly accounts
      receivable and accounts payable agings, and a certification of compliance
      with the borrowing base in the Borrowing Base Addendum attached hereto,
      executed by Borrower, which certificate shall accurately report Borrower's
      Accounts, Eligible Accounts, Inventory, and Eligible Inventory; and

      (e) Promptly upon request, any other financial information requested by
      Bank.

  4.4   Furnish to Bank, on Bank's request, a copy of Borrower's and each
  guarantor's most recently filed federal income tax return with all
  accompanying schedules.

  4.5   Pay or reimburse Bank for all costs, expenses and fees incurred by Bank
  in preparing and documenting this Agreement and the Loan, and all amendments
  and modifications thereof, including but not limited to all filing and
  recording fees, costs of appraisals, insurance and attorney's fees, including
  the reasonable estimate of the allocated costs and expenses of in-house legal
  counsel and staff.
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  4.6   Maintain and preserve Borrower's existence, present form of business and
  all rights, privileges and franchises necessary or desirable in the normal
  course of its business, and keep all of Borrower's properties in good working
  order and condition.

  4.7   Maintain and keep in force insurance with companies acceptable to Bank
  and in such amounts and types, including without limitation fire and public
  liability insurance, as is usual in the business carried on by Borrower, or as
  Bank may reasonably request.  Such insurance policies must be in form and
  substance satisfactory to Bank.

  4.8   Maintain adequate books, accounts and records and prepare all financial
  statements required hereunder in accordance with generally accepted accounting
  principles, and in compliance with the regulations of any governmental
  regulatory body having jurisdiction over Borrower or Borrower's business and
  permit employees or agents of Bank at any reasonable time to inspect
  Borrower's assets and properties, and to examine or audit Borrower's books,
  accounts and records and make copies and memoranda thereof.

  4.9   At all times comply with, or cause to be complied with, all laws,
  statutes, rules, regulations, orders and directions of any governmental
  authority having jurisdiction over Borrower or Borrower's business, and all
  material agreements to which Borrower is a party.

  4.10  Except as provided in this Agreement, or in the ordinary course of its
  business as currently conducted, not make any loans or advances, become a
  guarantor or surety, pledge its credit or properties in any manner, or extend
  credit.

  4.11  Not purchase the debt or equity of another person or entity except for
  savings accounts and certificates of deposit of Bank, direct U.S. Government
  obligations and commercial paper issued by corporations with top ratings of
  Moody's or Standard & Poor's, provided that all such permitted investments
  shall mature within one year of purchase.

  4.12  Not create, assume or suffer to exist any mortgage, encumbrance,
  security interest, pledge or lien ("Lien") on Borrower's real or personal
  property, whether nor owned or hereafter acquired, or upon the income or
  profits thereof except the following: (a) Liens in favor of Bank, (b) Liens
  for taxes or other items not delinquent or contested in good faith, or (c )
  other Liens which do not exceed in the aggregate $50,000 at any one time.

  4.13  Not sell or discount any account receivable or evidence of indebtedness,
  except to Bank; not borrow any money or become contingently liable for money
  borrowed, except pursuant to agreements made with Bank.

  4.14  Neither liquidate, dissolve, enter into any consolidation, merger,
  partnership, or other combination; nor convey, sell or lease all or the
  greater part of its assets or business; nor purchase or lease all or the
  greater part of the assets or business of another.

  4.15  Not engage in any business activities or operations substantially
  different from or unrelated to present business activities and operations.

  4.16  Not, in any single fiscal year of Borrower, expend or incur obligations
  of more than $200,000.

  4.17  Not, in any single fiscal year of Borrower, enter into any lease of real
  or personal property which would cause Borrower's aggregate annual obligations
  under all such real and personal property leases to exceed $NA.

  4.18  Borrower will promptly, upon demand by Bank, take such further action
  and execute all such additional documents and instruments in connection with
  this Agreement as Bank in its reasonable discretion deems necessary, and
  promptly supply Bank with such other information concerning its affairs as
  Bank may request from time to time.
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5.   EVENTS OF DEFAULT.  The occurrence of any of the following events ("Events
of Default") shall terminate any obligation on the part of Bank to make or
continue the Loan and automatically, unless otherwise provided under the Loan
Documents, shall make all sums of interest and principal and any other amounts
owing under the Loan immediately due and payable, without notice of default,
presentment or demand for payment, protest or notice of nonpayment or dishonor,
or any other notices or demands:

  5.1   Borrower shall default in the due and punctual payment of the principal
  of or the interest on the Note or any of the Loan Documents;

  5.2   Any default shall occur under the Note;

  5.3   Borrower shall default in the due performance or observance of any
  covenant or condition of the Loan Documents;

  5.4   Any guaranty or subordination agreement required hereunder is breached
  or becomes ineffective, or any guarantor or subordinating creditor dies or
  disavows or attempts to revoke or terminate such guaranty or subordination
  agreement; or

  5.5   There is a change in ownership or control of 10% or more of the issued
  and outstanding stock of Borrower or any guarantor, or (if the Borrower is a
  partnership) there is a change in ownership or control of any general
  partner's interest.

6.   MISCELLANEOUS.

  6.1   The rights, powers and remedies given to Bank hereunder shall be
  cumulative and not alternative and shall be in addition to all rights, powers,
  and remedies given to Bank by law against Borrower or any other person,
  including but not limited to Bank's rights of setoff or banker's lien.

  6.2   Any forbearance or failure or delay by Bank in exercising any right,
  power or remedy hereunder shall not be deemed a waiver thereof and any single
  or partial exercise of any right, power or remedy shall not preclude the
  further exercise thereof.  No waiver shall be effective unless it is in
  writing and signed by an officer of Bank.

  6.3   The benefits of this Agreement shall inure to the successors and assigns
  of Bank and the permitted successors and assignees of Borrower, and any
  assignment by Borrower without Bank's consent shall be null and void.

  6.4   This Agreement and all other agreements and instruments required by Bank
  in connection herewith shall be governed by and construed according to the
  laws of the State of California.

  6.5  Should any one or more provisions of this Agreement be determined to be
  illegal or unenforceable, all other provisions nevertheless shall be
  effective.  In the event of any conflict between the provisions of this
  Agreement and the provisions of any note or reimbursement agreement evidencing
  any indebtedness hereunder, the provisions of such note or reimbursement
  agreement shall prevail.

  6.6   Except for documents and instruments specifically referenced herein,
  this Agreement constitutes the entire agreement between Bank and Borrower
  regarding the Loan and all prior communications, verbal or written, between
  Borrower and Bank shall be of no further effect or evidentiary value.

  6.7   The section and subsection headings herein are for convenience of
  reference only and shall not limit or otherwise affect the meaning hereof.

  6.8   This Agreement may be amended only in writing signed by all parties
  hereto.
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  6.9   Borrower and Bank may execute one or more counterparts to this
  Agreement, each of which shall be deemed an original, but taken together shall
  be one and the same instrument.

  6.10   Any notices or other communications provided for or allowed hereunder
  shall be effective only when given by one of the following methods and
  addressed to the respective party at its address given with the signatures at
  the end of this Agreement and shall be considered to have been validly given:
  (a) upon delivery, if delivered personally; (b) upon receipt, if mailed, first
  class postage prepaid, with the United States Postal Service; (c) on the next
  business day if sent by overnight courier service of recognized standing; and
  (d) upon telephoned confirmation of receipt, if telecopied.

7.   ADDITIONAL PROVISIONS. The following additional provision, if any, are
hereby made part of this Agreement:

  7.1   Advances drawn under the Revolving Loan shall be in amounts of not less
  than $10,000.00 each.

  7.2  Advances drawn under the Term Loan shall be in amounts of not less than
  $50,000.00 each.

IN WITNESS WHEREOF, the parties hereto have duly executed this Agreement as of.
 
Union Bank of California, N.A. ("Bank")

By:            /S/ Jim Heim
Title:         Vice President
Printed Name:  Jim Heim

By:            /S/ Kim Ha
Title:         Vice President
Printed Name:  Jim Heim

Address where notices to Bank are to be sent:

500 S. Main Street, Suite 200
Orange, CA 92868
Fax 714-565-5725


("Borrower")

Research Engineers, Inc

By:            /S/ Brian Paul
Title:         Chief Financial Officer
Printed Name:  Brian Paul

Address where notices to Bank are to be sent:

22700 Savi Ranch Parkway
Yorba Linda, CA 92887
Fax 714-974-4771