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                                                                   Exhibit 10.72


               REVOLVING CREDIT FACILITY AND SECURITY AGREEMENT

      THIS REVOLVING CREDIT FACILITY AND SECURITY AGREEMENT ("Agreement") is
made as of the 31st day of December, 1996 by and between LCC INTERNATIONAL,
INC., a Delaware corporation whose principal office is located at Courthouse
Plaza II, 2300 Clarendon Boulevard, Arlington, Virginia 22201 (the "Lender"),
and MICROCELL MANAGEMENT, INC., a Delaware corporation whose principal office is
located at 1300 Bellona Avenue, Timonium, Maryland 21093 (the "Borrower").

                                    RECITALS

      WHEREAS, Borrower is engaged in the business of the acquisition,
build-out and operation of wireless communications towers;

      WHEREAS, Borrower is an eighty-three and seventy-five one hundredths
percent (83.75%) held subsidiary of Lender;

      WHEREAS, Borrower and Lender desire to provide for certain loan advances
to be made by Lender to Borrower to finance Borrower's operations on the terms
and conditions set forth herein;

      WHEREAS, each of the Borrower and Lender acknowledges that it will receive
substantial direct and indirect benefits by reason of the making of advances to
the Borrower as provided in this Agreement, including, without limitation, by
virtue of the interrelationship between the Borrower and the Lender;

      NOW, THEREFORE, for the promises made herein and other valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties agree as follows:

      1.    Definitions.

            (a)   General Terms.  When used herein, the following terms shall
have the following meanings:

                  "Accounts" shall mean the Borrower's presently existing and
hereafter arising or acquired accounts, accounts receivable, book debts, notes,
drafts, acceptances, chattel paper, and other forms of obligations now or
hereafter owned or held by or payable to the Borrower relating in any way to
Inventory (as hereinafter defined) or arising from the sale of Inventory or the
rendering of services by the Borrower or howsoever otherwise arising, including
the right to payment of any interest or finance charges with respect thereto,
together with all merchandise represented by any of the foregoing; all such
merchandise that may be reclaimed or repossessed or returned to the Borrower;
all of the Borrower's rights as an unpaid vendor, including stoppage in transit,
reclamation, replevin, and 


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sequestration; all pledged assets and all letters of credit, guaranty claims,
liens, and security interests held by or granted to the Borrower to secure
payment of any of the foregoing; all proceeds and products of all of the
foregoing described properties and interests in properties; all proceeds of
insurance with respect thereto, including the proceeds of any applicable credit
insurance or fidelity bond, whether payable in cash or in kind; and all ledgers,
books of account, records, computer programs, computer disks or tape files,
computer printouts, computer runs, and other computer prepared information
relating to any of the foregoing.

                  "Collateral" shall mean all property and interests in property
now owned or hereafter acquired by the Borrower in or upon which a security
interest, lien or mortgage is granted to the Lender by the Borrower under this
Agreement or under any other documents, instruments or writings executed by the
Borrower and delivered to the Lender, including, without limitation, Accounts,
General Intangibles, Inventory, Intellectual Property, Fixtures, Equipment and
Real Estate (each as defined herein).

                  "Default" shall mean an event which through the passage of
time or the service of notice or both would mature into an Event of Default (as
hereinafter defined).

                  "Equipment" shall mean Borrower's machinery and equipment,
including, without limitation, data processing and computer equipment with
software and peripheral equipment, and all engineering, processing and
manufacturing equipment, office machinery, furniture, materials handling
equipment, tools, attachments, accessories, automotive equipment, trailers,
trucks, motor vehicles, rolling stock and other equipment of every kind and
nature, and Fixtures (as hereinafter defined) not forming a part of real estate,
all whether now owned or hereafter acquired, and wherever situated, together
with all additions and accessions thereto, replacements therefor, all parts
therefor, all substitutes for any of the foregoing, fuel therefor, and all
manuals, drawings, instructions, warranties and rights with respect thereto, and
all products and proceeds thereof and condemnation awards and insurance proceeds
with respect thereto.

                  "Event of Default" shall mean the occurrence or existence of
any one or more of the following events: (i) the Borrower shall fail to pay
principal immediately when the same is due or declared due hereunder and the
same shall remain unpaid thirty (30) days after notice thereof by the Lender to
the Borrower; (ii) the Borrower shall fail to pay interest immediately when the
same is due or declared due hereunder and the same shall remain unpaid thirty
(30) days after notice thereof by the Lender to the Borrower; (iii) the Borrower
fails to pay any of its Obligations (as hereinafter defined) (other than as set
forth in clauses (i) or (ii) above) within ten (10) days after such Obligations
are due or are declared due in accordance herewith and the same shall remain
unpaid thirty (30) days after notice thereof by the Lender to the Borrower; (iv)
the Borrower fails or neglects to perform, 

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keep or observe any of the covenants, conditions or agreements contained in this
Agreement for a period of thirty (30) days or more after notice thereof by the
Lender to the Borrower (other than occurrences referred to or embodied in other
provisions of this subsection which shall constitute immediate Events of
Default, unless a grace period is otherwise specified in the description
thereof); (v) any warranty or representation now or hereafter made by the
Borrower in connection with this Agreement is untrue or incorrect in any
material respect, or any written schedule, certificate, statement, report,
financial data, notice, or other writing required to be furnished hereunder at
any time by the Borrower to the Lender is untrue or incorrect in any material
respect as of the date on which the warranty, representation or the facts set
forth therein are stated, certified or deemed made; (vi) all or any part of the
Collateral or the assets (with a fair market value in excess of two hundred and
fifty thousand dollars ($250,000)) of the Borrower are attached, seized,
subjected to a writ or distress warrant, or levied upon, or come within the
possession or control of any creditor of the Borrower and on or before the
thirtieth (30th) day thereafter such Collateral or assets are not returned to
the Borrower, or such writ, distress warrant or levy is not dismissed, stayed or
lifted; (vii) the Borrower makes an assignment for the benefit of creditors;
convenes a meeting of its creditors, or any class thereof, for purposes of
effecting a moratorium upon or extension or composition of its debts; commences
any bankruptcy, reorganization or insolvency proceeding or other proceeding
under any federal, state, provincial or other law for relief of debtors or
proposes, authorizes or consents to the taking of any of the foregoing actions;
(viii) the Borrower fails to obtain the dismissal, within thirty (30) days after
the commencement thereof, of any bankruptcy, reorganization or insolvency
proceeding, or other proceeding under any law for the relief of debtors
instituted against it; fails actively to oppose any such proceeding; or in any
such proceeding, defaults or files an answer admitting the material allegations
upon which the proceeding was based or states in any filing in such proceeding
its willingness to have an order for relief entered or its desire to seek
liquidation, reorganization or adjustment of any of its debts; (ix) any
receiver, trustee or custodian is appointed to take possession of all or any
substantial portion of the assets of the Borrower or any committee of the
Borrower's creditors is formed for the purpose of enforcing such creditors'
rights; (x) the Borrower voluntarily or involuntarily dissolves or is dissolved,
liquidates or is liquidated or ceases to be solvent or admits in writing that it
is not solvent or fails to pay all or any material portion of its debts as they
become due or admits in writing its present or prospective inability to pay its
debts as they become due; or (xi) any material term or provision of this
Agreement for any reason shall cease to be valid and binding on or become
unenforceable against the Borrower or the Borrower shall so state or assent in
writing. The occurrence or existence of any of the foregoing events shall
constitute an immediate Event of Default unless notice or further notice, as the
case may be, by the Lender or a cure period is specifically required by the
description of such event before such event matures into an Event of Default.

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                  "Fixtures" shall mean all "fixtures" as such term is defined
in the Uniform Commercial Code, now owned or hereafter acquired by the Borrower.

                  "General Intangibles" shall mean the Borrower's presently
owned or hereafter acquired goodwill, choses in action, causes of action,
franchises, methods, sales literature, drawings, specifications, descriptions,
confidential information, consulting agreements, employment agreements,
engineering contracts, leasehold interests in real and personal property,
insurance policies (including business interruption insurance, if any) and such
other assets which uniquely reflect the goodwill of the business of the
Borrower; deposit amounts, letters of credit, and general intangibles relating
to other items of Collateral, including without limitation, rights to refunds or
indemnification, reversionary or other rights of the Borrower to excess employee
benefit plan assets upon termination or amendment thereof; and proceeds of all
of the foregoing, including without limitation, insurance proceeds, including
proceeds of business interruption insurance, income tax refunds, and claims for
tax or other refunds against any city, county, state, or federal government, or
any agency or authority or other subdivision thereof.

                  "Intellectual Property" shall mean the Borrower's present and
future designs, patents, patent rights and applications therefor, trademarks and
registrations or applications therefor, trade names, service marks, inventions,
copyrights and all applications and registrations therefor, software or computer
programs, license rights, trade secrets, methods, processes, know-how, drawings,
specifications, descriptions, and all memoranda, notes, and records with respect
to any research and development, and any interest of the Borrower in the
foregoing, whether now owned or hereafter acquired by the Borrower and proceeds
of all of the foregoing, including, without limitation, proceeds of insurance
policies thereon.

                  "Inventory" shall mean all of the inventory of the Borrower of
every kind and description, now or at any time hereafter owned by or in the
custody or possession, actual or constructive, of the Borrower, wherever
located, including, but not limited to, all merchandise, raw materials, parts,
supplies, work-in-process and finished goods intended for sale, together with
all the containers, packing, packaging, shipping and similar materials related
thereto, and including such inventory as is temporarily out of the Borrower's
custody or possession, including inventory on the premises of others and items
in transit, and including any returns and repossessions upon any accounts,
documents, instruments or chattel paper relating to or arising from the sale of
inventory, and all substitutions and replacements therefor, and all additions
and accessions thereto, and all ledgers, books of account, records, computer
printouts, computer runs, and other computer-prepared information relating to
any of the foregoing, and any and all proceeds of any of the foregoing,
including, without limitation, proceeds of insurance policies thereon.

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                  "Obligations" shall mean all of the Borrower's obligations,
liabilities and indebtedness to the Lender of any and every kind and nature,
whether heretofore, now or hereafter owing, arising, existing, due or payable
and howsoever evidenced, created, incurred, or owing, whether primary,
secondary, direct, indirect, contingent, fixed or otherwise (including
obligations of performance) in connection with this Agreement or by operation of
law.

                  "Uniform Commercial Code" shall mean the Uniform Commercial
Code of the State of Delaware or of any other state which may be applicable in
connection with the issue of perfection or non-perfection of security interests
in the Collateral.

      2.    The Revolving Credit Facility.

            (a) Subject to and upon the provisions of this Agreement, the Lender
establishes a revolving credit facility in favor of the Borrower. The aggregate
of all advances under the revolving credit facility are sometimes referred to in
this Agreement collectively as the "Revolving Loan." The maximum aggregate
principal amount of the Revolving Loan is Thirty-Five Million United States
Dollars (US$35,000,000).

            (b) During the term of this Agreement, the Lender agrees to make
advances under the Revolving Loan as requested by the Borrower from time to
time; provided that, after giving effect to the Borrower's request to borrow,
the outstanding principal balance of the Revolving Loan would not exceed
Thirty-Five Million United States Dollars (US$35,000,000).

            (c) The Borrower shall not make a request for an advance, and the
Lender shall not be obligated to make such advances, under the Revolving Loan
unless a majority of the Borrower's directors have voted in favor of making such
request.

      3.    Procedure for Making Advances Under the Revolving Loan. The Borrower
shall make any request for an advance under the Revolving Loan in writing to the
Lender and shall attach a copy of executed resolutions of the Borrower's
directors authorizing such request. The Lender shall have ten (10) business days
from the receipt of such written request to make such advance to the Borrower.

      4.    Revolving Credit Note. The obligation of the Borrower to pay the
Revolving Loan with interest shall be evidenced by a separate promissory note
payable to the Lender (as from time to time extended, amended, restated,
supplemented or otherwise modified, the "Revolving Credit Note") substantially
in the form of Exhibit A attached hereto, with appropriate insertions. The
Revolving Credit Note shall be dated as of the date of the first advance under
the Revolving Loan, shall be payable to the order of the Lender, at the times
provided in the 

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Revolving Credit Note and shall be in the principal amount of Thirty-Five
Million United States Dollars (US$35,000,000).

      5.    Optional Prepayments of Revolving Loan. The Borrower may, at its
option, at any time and from time to time prepay the principal sum outstanding
under the Revolving Loan, in whole or in part, without premium or penalty. Any
amount of principal prepaid by Borrower shall then be available for the Borrower
to re-borrow in accordance with the provisions of Section 2, above.

      6.    Revolving Loan Account. The Lender will establish and maintain a 
loan account on its books for the Borrower (the "Revolving Loan Account") to
which the Lender will (a) debit (i) the principal amount of the Revolving Loan
made by the Lender hereunder as of the date made, and (ii) the amount of any
interest accrued on the Revolving Loan made by the Lender as and when due, and
(b) credit all payments made by the Borrower to the Lender on account of the
Revolving Loan as of the date made. Absent manifest error, any and all periodic
or other statements or reconciliations, and the information contained in those
statements or reconciliations, of the Revolving Loan Account shall be presumed
conclusively to be correct and shall constitute an account stated between the
Borrower and the Lender.

      7.    Interest. Each advance made hereunder shall bear interest on the
unpaid principal amount thereof at a rate per annum equal to the prime rate as
published in the Wall Street Journal from time to time. Interest shall be
computed on the basis of a year of three hundred sixty (360) days for the actual
number of days elapsed and shall be payable monthly. All payments made hereunder
shall be applied first to accrued and unpaid interest, and then to principal.

      8.    Security Interest. In consideration of the Revolving Loan, the
Borrower hereby assigns, conveys, mortgages, pledges, hypothecates and transfers
and hereby grants to the Lender a right of setoff against and a continuing lien
upon and security interest in and to all of the Borrower's right, title and
interest in and to the following property and interests in property, whether now
owned or hereafter acquired by the Borrower and wheresoever located: (i)
Accounts; (ii) General Intangibles; (iii) Fixtures; (iv) Inventory; (v)
Equipment; (vi) Intellectual Property; (vii) all of the Borrower's deposit
accounts (general or special) with any financial institution with which the
Borrower maintains deposits; (viii) all of the Borrower's now owned or hereafter
acquired monies, chattel paper, notes, documents, instruments and any and all
other property and interests in property of the Borrower; (ix) all insurance
policies relating to any of the foregoing, including without limitation business
interruption insurance; (x) all of the Borrower's books and records relating to
any of the foregoing; (xi) all accessions and additions to, substitutions for,
and replacements of any of the foregoing; and (xii) all cash collections from,
and all other cash and non-cash proceeds of, any of the foregoing. In addition,
the Borrower shall grant and convey to the Lender mortgage liens on 

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all real property of the Borrower hereafter acquired. The Lender's liens and
security interests shall be first and prior perfected liens or security
interests with respect to all Collateral.

      9.    Preservation of Collateral and Perfection. Simultaneously with the
execution of this Agreement and at any time or times hereafter at the request of
the Lender, the Borrower shall execute and deliver all financing statements,
security agreements, mortgages, amendments thereto, assignments and notices
thereof or other documents (and pay the cost of delivering, filing or recording
the same in all public or private offices deemed necessary by the Lender), as
the Lender may request, in a form satisfactory to the Lender, to perfect and
maintain the security interests in the Collateral granted by the Borrower to the
Lender or to otherwise protect and preserve the Collateral and the Lender's
security interests therein or to continue to enforce the Lender's security
interests in the Collateral. Should Borrower fail to do so, the Lender is
authorized to sign any such financing statements or other documents as the
Borrower's agent. Borrower further agrees that a carbon copy, photocopy or other
reproduction of this Agreement or of a financing statement is sufficient as a
financing statement.

      10.   Default and Acceleration of Obligations. If an Event of Default
shall exist or occur and be continuing, the Lender may terminate this Agreement
and upon notice of termination to the Borrower (a) the Obligations shall be
accelerated and all of the Obligations shall automatically, without further
notice of any kind, be immediately due and payable, provided that upon the
occurrence of any Event of Default referred to in paragraphs (vi), (vii), or
(viii), within the definition of "Event of Default," such termination and
acceleration shall be deemed to occur automatically without notice of any kind
being given to the Borrower or action of any kind being taken by the Lender.

      11.   Rights and Remedies Generally. Upon acceleration of the Obligations,
the Lender shall have, in addition to any other rights and remedies contained in
this Agreement, all of the rights and remedies of a secured party under the
Uniform Commercial Code or other applicable laws, all of which rights and
remedies shall be cumulative and non-exclusive, to the extent permitted by law.
In addition to all such rights and remedies, the Lender shall have the right to
sell, lease or otherwise dispose of all or any part of the Collateral and the
sale, lease or other disposition of the Collateral, or any part thereof, by the
Lender after an Event of Default may be for cash, credit or any combination
thereof, and the Lender may purchase all or any part of the Collateral at public
or, if permitted by law, private sale, and in lieu of actual payment of such
purchase price, may set-off the amount of such purchase price against the
Obligations then owing. Any sales of the Collateral may be adjourned from time
to time with or without notice. The Lender may, in its sole discretion, cause
the Collateral to remain on the Borrower's premises or otherwise or to be
removed and stored at premises owned by other persons, at the Borrower's
expense, pending sale or other disposition of the Collateral. The Lender shall
have 

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the right to conduct such sales on the Borrower's premises, at the Borrower's
expense, or elsewhere, on such occasion or occasions as the Lender may see fit.

      12.   Entry Upon Premises and Access to Information. Upon acceleration of
the Obligations, the Lender shall have the right to enter upon the premises of
the Borrower where the Collateral is located (or is believed to be located)
without any obligation to pay rent to the Borrower, or any other place or places
where the Collateral is believed to be located and kept, to render the
Collateral usable or salable, to remove the Collateral therefrom to the premises
of the Lender or any agent of the Lender for such time as the Lender may desire
in order effectively to collect or liquidate the Collateral, and/or to require
the Borrower to assemble the Collateral and make it available to the Lender at a
place or places to be designated by the Lender. Upon acceleration of the
Obligations, the Lender shall have the right to take possession of the
Borrower's original books and records, to obtain access to the Borrower's data
processing equipment, computer hardware and software relating to the Collateral
and to use all of the foregoing and the information contained therein in any
manner the Lender deems appropriate.

      13.   Sale or Other Disposition of Collateral by the Lender. Any notice
required to be given by the Lender of a sale, lease or other disposition or
other intended action by the Lender with respect to any of the Collateral which
is deposited in the United States mails, postage prepaid and duly addressed to
the Borrower at least ten (10) days prior to such proposed action, shall
constitute fair and reasonable notice to the Borrower of any such action. The
net proceeds realized by the Lender upon any such sale or other disposition,
after deduction for the expenses of retaking, holding, storing, transporting,
preparing for sale, selling or otherwise disposing of the Collateral incurred by
the Lender in connection therewith, shall be applied as provided herein toward
satisfaction of the Obligations. The Lender shall account to the Borrower for
any surplus realized upon such sale or other disposition, and the Borrower shall
remain liable for any deficiency. The commencement of any action, legal or
equitable, or the rendering of any judgment or decree for any deficiency shall
not affect the Lender's security interest in the Collateral until the
Obligations are fully paid. The Borrower agrees that the Lender has no
obligation to preserve rights to the Collateral against any other parties. Upon
acceleration of the Obligations in accordance with Section 10, the Lender is
hereby granted a license or other right to use, without charge, the Borrower's
General Intangibles, Intellectual Property, Equipment, Real Estate and
advertising matter, or any property of a similar nature, as it pertains to the
Collateral, in completing production of, advertising for sale or lease and
selling or leasing any Inventory or other Collateral and the Borrower's rights
under all licenses, leases and franchise agreements shall inure to the Lender's
benefit until all Obligations are paid in full.

      14.   Waiver of Demand. DEMAND, PRESENTMENT, PROTEST AND NOTICE OF DEMAND,
PRESENTMENT, PROTEST AND NONPAYMENT ARE 

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HEREBY WAIVED BY THE BORROWER. THE BORROWER ALSO WAIVES THE BENEFIT OF ALL
VALUATION, APPRAISAL AND EXEMPTION LAWS TO THE EXTENT PERMITTED BY LAW.

      15.   Waiver of Notice. IN THE EVENT OF AN EVENT OF DEFAULT, THE BORROWER
HEREBY WAIVES ALL RIGHTS TO NOTICE AND HEARING OF ANY KIND PRIOR TO THE EXERCISE
BY THE LENDER OF ITS RIGHTS TO REPOSSESS THE COLLATERAL WITHOUT JUDICIAL PROCESS
OR TO REPLEVY, ATTACH OR LEVY UPON THE COLLATERAL WITHOUT PRIOR NOTICE OR
HEARING. THE BORROWER ACKNOWLEDGES THAT IT HAS BEEN ADVISED BY COUNSEL OF ITS
CHOICE WITH RESPECT TO THIS TRANSACTION AND THIS AGREEMENT.

      16.   Term and Termination. This Agreement shall remain in effect until
the earlier to occur of: (i) the dissolution and liquidation of the Borrower; or
(ii) the termination of this Agreement by the Lender one hundred and twenty
(120) days after written notice thereof to the Borrower, whereupon the
Obligations shall be accelerated and all of the Obligations shall automatically,
without further notice of any kind, be immediately due and payable.

      17.   Miscellaneous.

            (a) This Agreement constitutes the complete and exclusive statement
of the terms and conditions between the parties with respect to the subject
matter hereof and supersedes and merges any prior understandings or agreements,
oral or written.

            (b) This Agreement shall be construed in accordance with and
governed by the laws of the State of Delaware (other than the laws of the State
of Delaware governing choice of law).

            (c) This Agreement shall be binding upon the parties and their
respective successors and assignees. No party may assign this Agreement, or any
of its rights, duties or obligations hereunder, in whole or in part, to any
person or entity without the prior written consent of the other party.

            (d) The waiver or failure of any party to exercise any right in any
respect provided for herein shall not be deemed a waiver of any other or further
right hereunder.

            (e) Any term or provision of this Agreement that is held invalid or
unenforceable by a court of competent jurisdiction in any situation in any
jurisdiction shall not affect the validity or enforceability of the remaining
terms and provisions hereof or the validity or enforceability of the offending
term or provision in any other situation or in any other jurisdiction. If the
final judgment of a court of competent jurisdiction declares that any term or
provision hereof is invalid or 


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unenforceable, the parties agree that the court making the determination of
invalidity or unenforceability shall have the power to reduce the scope,
duration, or area of the term or provision, to delete specific words or phrases,
or to replace any invalid or unenforceable term or provision with a term or
provision that is valid and enforceable and that comes closest to expressing the
intention of the invalid or unenforceable term or provision, and this Agreement
shall be enforceable as so modified after the expiration of the time within
which the judgment may be appealed.

            (f) This Agreement may not be amended, modified or altered except by
written instrument duly executed by each party expressly referencing this
Agreement and the parties' intent that it be so amended, modified or altered.

            (g) Each party represents that such party has full power and
authority to enter into this Agreement and perform its obligations hereunder.
Each party represents that the person signing this Agreement on its behalf has
been properly authorized and empowered to enter into this Agreement.

            (h) This Agreement may be executed in one or more counterparts and
may be executed by facsimile signature, each of which shall be deemed an
original but all of which together will constitute one and the same instrument.

                            [SIGNATURE PAGE FOLLOWS]


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      IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
and delivered by their respective officers thereunto duly authorized on the date
first above written.

                                 LCC INTERNATIONAL, INC.

                                 By:  /S/ PIYUSH SODHA
                                    ----------------------    
                                 Name:   Piyush Sodha
                                 Title:  President & Chief Executive Officer



                                 MICROCELL MANAGEMENT, INC.

                                 By: /S/ ALBERT F. GRIMES
                                    ------------------------    
                                 Name:   Albert F. Grimes
                                 Title:  President


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                                                                   EXHIBIT 10.74


                                                                       EXHIBIT A

                              REVOLVING CREDIT NOTE

US$35,000,000                                               December ___, 1996



      FOR VALUE RECEIVED, MICROCELL MANAGEMENT, INC., a Delaware corporation
("Maker"), promises to pay to the order of LCC INTERNATIONAL, INC., a Delaware
corporation ("Holder"), at 2300 Clarendon Boulevard, Suite 800, Arlington,
Virginia 22201, or at such other place as the Holder hereof may from time to
time designate in writing, the principal sum of Thirty-Five Million United
States Dollars (US$35,000,000), or so much thereof as has been or may be
advanced or readvanced to the Maker and remains outstanding pursuant to the
terms and conditions of the Revolving Credit Facility (as hereinafter defined),
together with accrued but unpaid interest thereon at the rate hereinafter
provided, in accordance with the following:

      1.    Interest. Commencing as of the date of each advance under the
Revolving Credit Facility and continuing until repayment in full of all sums due
hereunder, the unpaid principal sum shall bear interest at a rate per annum
equal to the prime rate as published in the Wall Street Journal as in effect
from time to time. Interest shall be computed on the basis of a year of three
hundred sixty (360) days for the actual number of days elapsed.

      2.    Payments and Maturity. The unpaid principal sum, together with
interest thereon at the rate provided above, shall be payable as follows:

            (a) Interest only on the unpaid principal sum shall be due and
payable monthly, commencing on the first day of the month following the month in
which this Revolving Credit Note is made, and on the first day of each month
thereafter to maturity; and

            (b) Unless sooner paid, the unpaid principal sum, together with
interest accrued and unpaid thereon, shall be due and payable upon the
termination of the Revolving Credit Facility.

      The advances made by the Holder to the Maker, all payments made on account
of principal hereof and all conversions of principal hereof, shall be recorded
by the Holder on the grid attached hereto which is a part of this Revolving
Credit Note. The fact that the balance hereunder may be reduced to zero from
time to time pursuant to the Revolving Credit Facility will not affect the
continuing validity of this Revolving Credit Note or the Revolving Credit
Facility, and the balance may be increased to the maximum principal sum of this
Revolving Credit Note after any such reduction to zero.


<PAGE>   13

      3.    Prepayment. The Maker may prepay the outstanding principal sum in
whole or in part at any time and from time to time without notice, premium or
penalty.

      4.    Revolving Credit Facility. This is the promissory note referred to
in the Revolving Credit Facility and Security Agreement dated of even date
herewith by and between the Maker and the Holder (as amended, modified,
restated, substituted, extended and renewed at any time and from time to time,
the "Revolving Credit Facility").

      5.    Events of Default. The occurrence of any one or more of the
following events shall constitute an event of default (individually, an "Event
of Default" and collectively, the "Events of Default") under the terms of this
Revolving Credit Note:

            (a) The failure of the Maker to pay to the Holder when due any and
all amounts payable by the Maker to the Holder under the terms of this Revolving
Credit Note, but only if the Maker fails to cure such default within thirty (30)
days after the Holder shall have sent the Maker written notice of such default
(to the Maker's last known address); or

            (b) The occurrence of an event of default under the Revolving Credit
Facility.

      6.    Remedies. Upon the occurrence of an Event of Default, at the option
of the Holder, all amounts payable by the Maker to the Holder under the terms of
this Revolving Credit Note shall immediately become due and payable. Failure to
exercise this option shall not constitute a waiver of the right to exercise the
same in the event of any subsequent default.

      7.    Security. This Revolving Credit Note is secured pursuant to the
Revolving Credit Facility and reference is made thereto for a statement of the
terms and conditions of such security.

      8.    Waiver. Maker hereby waives demand, presentment, protest, notice of
demand, presentment, protest and nonpaymant. Maker also waives all rights to
notice and hearing of any kind upon the occurrence of an Event of Default prior
to the exercise by Holder of its rights to repossess the Collateral (as defined
in the Revolving Credit Facility) without judicial process or to replevy, attach
or levy upon the Collateral without notice or hearing.

      9.    Miscellaneous.

            (a) Any term or provision of this Revolving Credit Note that is
invalid or unenforceable in any situation in any jurisdiction shall not affect
the validity or enforceability of the remaining terms and provisions hereof or
the validity or enforceability of the offending term or provision in any other
situation or 


                                       2
<PAGE>   14

in any other jurisdiction. If the final judgment of a court of competent
jurisdiction declares that any term or provision hereof is invalid or
unenforceable, the court making the determination of invalidity or
unenforceability shall have the power to reduce the scope, duration, or area of
the term or provision, to delete specific words or phrases, or to replace any
invalid or unenforceable term or provision with a term or provision that is
valid and enforceable and that comes closest to expressing the intention of the
invalid or unenforceable term or provision, and this Revolving Credit Note shall
be enforceable as so modified after the expiration of the time within which the
judgment may be appealed.

            (b) This Revolving Credit Note may not be changed orally but only by
an agreement in writing signed by the party against whom enforcement of any
waiver, change, modification or discharge is sought expressly referencing this
Revolving Credit Note and such party's intent that such waiver, change,
modification or discharge be effected.

            (c) This Revolving Credit Note shall be interpreted in accordance
with the laws of the State of Delaware (other than the laws of the State of
Delaware governing choice of law).

            (d) This Revolving Credit Note is not negotiable.

                                    MAKER:

                                    MICROCELL MANAGEMENT, INC.

                                    By:
                                       --------------------------- 
                                    Name:    Albert F. Grimes
                                    Title:   President


                                       3
<PAGE>   15



                       ADVANCES AND PAYMENTS OF PRINCIPAL

<TABLE>
<CAPTION>
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                                    AMOUNT OF
                    AMOUNT OF     PRINCIPAL PAID   UNPAID PRINCIPAL      NOTATION
      DATE           ADVANCE        OR PREPAID          BALANCE           MADE BY
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<S>                <C>           <C>               <C>                  <C>  
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</TABLE>