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                                                                     EXHIBIT 4.2

                                 PROMISSORY NOTE



$100,000.00                                                Date:  March 26, 1999


         FOR VALUE RECEIVED, CHICAGO MAP CORPORATION, an Illinois corporation
("Borrower"), promises to pay to MARK A. SCHARMANN, an individual ("Lender"), or
order, the principal amount of ONE HUNDRED THOUSAND DOLLARS ($100,000.00) with
interest on the unpaid principal balance at one percent (1%) per month (the
"Loan").

         This Promissory Note is the Note referred to as Exhibit A to the
Interim Loan Agreement of even date herewith entered into by Borrower and
Lender. Pursuant to the terms of the Interim Loan Agreement, Lender has made the
Loan to Borrower as follows:

         1. Payment and Term. The Loan shall bear interest on the principal
balance at 1% per month from and after the date thereof until payment in full.
The principal and interest, is due and payable as follows:

                  (a) The Note is due in full three (3) months from the date
         hereof, unless extended by Lender pursuant to written notice thereof,
         or such other agreement as may be entered into between Lender and
         Borrower with respect thereto; and

                  (b) Borrower may, but is not obligated to, make periodic
         payments in part or full payment of the Loan, until due.

         2. Application of Payments. Unless applicable law provides otherwise,
all payments received by Lender shall be applied by Lender first in payment of
interest payable and next to the principal.

         3.1 Events of Default. Upon the occurrence and during the continuance
of any one or more events hereinafter enumerated, Lender may forthwith or at any
time thereafter during the continuance of any such event, by notice in writing
to Borrower, declare the unpaid balance of the principal and interest then
accrued on the Note to be immediately due and payable, and the principal and
interest shall become and shall be immediately due and payable without
presentation, demand, protest, notice of protest, or other notice of dishonor,
all of which are hereby expressly waived by Borrower, such events being as
follows:

                  (a) Default in the payment of the principal and interest of
         the Note or any portion thereof when the same shall become due and
         payable, whether at maturity as therein expressed, by acceleration, or
         otherwise, unless cured within 10 days after notice thereof by the
         holder of such Note to Borrower;


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                  (b) The creditors under any priority secured indebtedness of
         Borrower shall declare the amounts due thereunder to be due and payable
         following default;

                  (c) Default in the due observance or performance of any other
         covenant or obligation contained in the Interim Loan Agreement, this
         Note or the Acquisition Agreement unless observed or performed within
         10 days after notice thereof to Borrower by Lender; provided, if
         compliance is not possible within 10 days, default shall occur upon
         failure within 10 days to take steps that will produce compliance as
         soon as is reasonably practicable;

                  (d) Any representation or warranty herein or in the
         Acquisition Agreement made by Borrower proves to have been untrue in
         any material respect as of the date as of which the facts therein set
         forth were stated or certified, and corrective measures, satisfactory
         to Lender with respect thereto shall not have been taken within 10 days
         after notice thereof to Lender; provided, if compliance is not possible
         within 10 days, default shall occur upon failure within 10 days to take
         steps that will produce compliance as is reasonably practicable;

                  (e) Borrower shall file a voluntary petition in bankruptcy or
         a voluntary position seeking reorganization, or shall file an answer
         admitting the jurisdiction of the court and any material allegations of
         an involuntary petition filed pursuant to any act of Congress relating
         to bankruptcy or to any act purporting to be amendatory thereof, or
         shall be adjudicated bankrupt, or shall make an assignment for the
         benefit of creditors, or shall apply for or consent to the appointment
         of any receiver or trustee for Borrower, or of all or any substantial
         portion of its property, or Borrower shall make an assignment to an
         agent authorized to liquidate any substantial part of its assets;

                  (f) An order shall be entered pursuant to any act of Congress
         relating to bankruptcy or to any act purporting to be amendatory
         thereof approving an involuntary petition seeking reorganization of
         Borrower, or an order of any court shall be entered appointing any
         receiver or trustee of or for Borrower, or any receiver or trustee of
         all or any substantial portion of the property of Borrower, or a writ
         or warrant of attachment or any similar process shall be issued by any
         court against all or any substantial portion of the property of
         Borrower, and such order approving a petition seeking reorganization or
         appointing a receiver or trustee is not vacated or stayed, or such
         writ, warrant of attachment, or similar process is not released or
         bonded within 60 days after its entry or levy; or

                  (g) The rendering against the Borrower of final judgment for
         the payment of money in excess of $25,000 and failure of the Borrower
         to appeal therefrom (or from the order, decree, or process pursuant to
         which such judgment was granted, passed, entered, or affirmed) and
         obtain a stay of execution thereof within the period prescribed by law
         for appeal, or to have such judgment discharged and satisfied within 60
         days after the expiration of such period or of the period of any such
         stay, whichever shall later occur.

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         3.2 Procedure on Default. Upon the occurrence of an event of default,
and at any time thereafter, Lender may elect to declare the entire Note
immediately due and payable.

                  (a) In the event of default in the payment of said Note when
         due or declared due, Lender shall have all the rights and remedies of a
         secured party and shall be entitled to avail itself of all such other
         rights and remedies that may now or hereafter exist at law or in equity
         for the collection of the Note and the enforcement of the covenants
         herein and the foreclosure of the security interest created hereby and
         resort to any remedy provided hereunder or provided by the Illinois
         Uniform Commercial Code, or by any other law of the state of Illinois,
         shall not prevent the concurrent or subsequent employment of any other
         appropriate remedy or remedies; and

                  (b) The requirement of reasonable notice to Borrower of the
         time and place of any public sale of the security or of the time after
         which any private sale, or any other intended disposition thereof is to
         be made, shall be met if such notice is mailed, postage prepaid, to
         Borrower at the address of such party designated below, at least 30
         days before the date of any public or private sale or other disposition
         is to be made.

         3.3 Defaults Under Prior Indebtedness. Upon the default by Borrower of
any term, covenant, or condition required to be performed by if on any priority
secured indebtedness or the receipt by Borrower from any such priority secured
creditor of notice of any default under such indebtedness, whether or not
repayment of the indebtedness is accelerated, Borrower shall promptly advise
Lender in writing of the nature and amount of default and of the action, if any,
threatened by such priority secured creditor. Notwithstanding the Borrower's
obligation to cure any and all such defaults, Lender may, but shall not be
obligated to do so, in the name, place, and stead of Borrower and, in the case
of such curative efforts by Lender, succeed to all of the rights, remedies, and
security of such priority creditor.

         4. Attorneys' Fees. If this Note is placed with an attorney for
collection, or is suit be instituted for collection, or if any other remedy
permitted by law is pursued by Lender, because of any default in the terms and
conditions herein, then in such event, the undersigned agrees to pay reasonable
attorneys' fees, costs, and other expenses incurred by Lender in so doing.

         5. Governing Law. This Master Note shall be governed by and construed
and enforced in accordance with the laws of the state of Illinois.

         6. Security Interest. Borrower shall execute a Security Agreement and
an Escrow Agreement wherein Borrower shall grant to Lender a security interest
in the Collateral as defined in the Interim Loan Agreement, sufficient to secure
the obligation created hereunder, which agreements shall be made a part of the
Interim Loan Agreement and this Note and incorporated herein by this reference.





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                                    BORROWER:

                                    CHICAGO MAP CORPORATION,
                                    an Illinois corporation



                                    By: /s/ John B. McLean
                                       -----------------------------------------
                                       Its Duly Authorized Representative