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                                                                 EXHIBIT 10.2

                                IMPORTANT NOTICE

THIS INSTRUMENT CONTAINS A CONFESSION OF JUDGMENT PROVISION THAT CONSTITUTES A
WAIVER OF IMPORTANT RIGHTS YOU MAY HAVE AS A DEBTOR AND ALLOWS THE CREDITOR TO
OBTAIN A JUDGMENT AGAINST YOU WITHOUT ANY FURTHER NOTICE.

               AMENDED AND RESTATED REVOLVING CREDIT PROMISSORY NOTE

$3,000,000                                                    McLean, Virginia
                                                             February 28, 1999

      FOR VALUE RECEIVED, SENSYS TECHNOLOGIES INC., a corporation organized
under the laws of the State of Delaware (the "Borrower"), promises to pay to
the order of NATIONSBANK, N. A., a national banking association (the "Lender"),
the principal sum of THREE MILLION DOLLARS ($3,000,000) (the "Principal Sum"),
or so much thereof as has been or may be advanced or readvanced to or for the
account of the Borrower pursuant to the terms and conditions of the Financing
Agreement (as hereinafter defined), together with interest thereon at the rate
or rates hereinafter provided, in accordance with the following:

      1.     Interest.

      Commencing as of the date hereof and continuing until repayment in full
of all sums due hereunder, the unpaid Principal Sum shall bear interest at the
Applicable Interest Rate or the Post Default Rate in effect from time to time
pursuant to the terms of the Financing Agreement. The Applicable Interest Rate
shall be determined in the manner provided in the Financing Agreement.

      2.     Payments and Maturity.

      The unpaid Principal Sum, together with interest thereon, shall be
payable as follows:

            (a) Interest only on the unpaid Principal Sum shall be due and
payable on the Interest Payment Date (as that term is defined in the Financing
Agreement); and

            (b) Unless sooner paid, the unpaid Principal Sum, together with
interest accrued and unpaid thereon, shall be due and payable in full on the
Revolving Credit Expiration Date (as that term is defined in the Financing
Agreement).

      The fact that the balance hereunder may be reduced to zero from time to
time pursuant to the Financing Agreement will not affect the continuing
validity of this Note or the Financing Agreement, and the balance may be
increased to the Principal Sum after any such reduction to zero.

      The Lender is authorized to deduct any payment due hereunder from the
Borrower's account #37500119089 issued by the Lender, on or after the date the
payment is due.


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      3.     Default Interest.

      Upon the occurrence of an Event of Default (as hereinafter defined), the
unpaid Principal Sum shall bear interest thereafter at a rate four percent (4%)
per annum in excess of the Applicable Interest Rate until such Event of Default
is cured.

      4.     Late Charges.

      If the Borrower shall fail to make any payment under the terms of this
Note within fifteen (15) days after the date such payment is due, the Borrower
shall pay to the Lender on demand a late charge equal to five percent (5%) of
such payment.

      5.     Application and Place of Payments.

      All payments, made on account of this Note shall be applied first to the
payment of any late charge then due hereunder, second to the payment of accrued
and unpaid interest then due hereunder, and the remainder, if any, shall be
applied to the unpaid Principal Sum. All payments on account of this Note shall
be paid in lawful money of the United States of America in immediately
available funds during regular business hours of the Lender at its principal
office in Baltimore, Maryland or at such other times and places as the Lender
may at any time and from time to time designate in writing to the Borrower.

      6.     Prepayment.

            (c) Mandatory Prepayments. The Borrower shall make mandatory
prepayments of the Revolving Loan as required to comply with the provisions of
Section 2.1.6 of the Financing Agreement.

            (d) Voluntary Prepayments. Subject to the provisions of the
Financing Agreement, the Borrower may voluntarily prepay the Revolving Loan at
any time without premium or penalty.

      7.     Financing Agreement and Other Financing Documents.

      This Note is the "Revolving Credit Note" described in an Amended and
Restated Financing and Security Agreement of even date herewith by and between
the Borrower and the Lender (the "Financing Agreement"). The indebtedness
evidenced by this Note is included within the meaning of the term "Obligations"
as defined in the Financing Agreement. The term "Financing Documents" as used
in this Note shall mean collectively this Note, the Financing Agreement and any
other instrument, agreement, or document previously, simultaneously, or
hereafter executed and delivered by the Borrower and/or any other person,
singularly or jointly with any other person, evidencing, securing,
guaranteeing, or in connection with the Principal Sum, this Note and/or the
Financing Agreement.

      8.     Security.

      This Note is secured as provided in the Financing Agreement.



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      9.     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 Note:

            (a) The failure of the Borrower to pay to the Lender when due any
and all amounts payable by the Borrower to the Lender under the terms of this
Note; or

            (b) The occurrence of an event of default (as defined therein)
under the terms and conditions of any of the other Financing Documents.

      10.    Remedies.

      Upon the occurrence of an Event of Default, at the option of the Lender,
all amounts payable by the Borrower to the Lender under the terms of this Note
shall immediately become due and payable by the Borrower to the Lender without
notice to the Borrower or any other person, and the Lender shall have all of
the rights, powers, and remedies available under the terms of this Note, any of
the other Financing Documents and all applicable laws. The Borrower and all
endorsers, guarantors, and other parties who may now or in the future be
primarily or secondarily liable for the payment of the indebtedness evidenced
by this Note hereby severally waive presentment, protest and demand, notice of
protest, notice of demand and of dishonor and non-payment of this Note and
expressly agree that this Note or any payment hereunder may be extended from
time to time without in any way affecting the liability of the Borrower,
guarantors and endorsers.

      11.    Confessed Judgment.

      The Borrower hereby appoints and designates Amy S. Owen, Esquire and
Brian F. Kenney, Esquire, respectively and individually, the Borrower's duly
constituted attorney-in-fact to confess judgment against the Borrower pursuant
to the provisions hereof and of Section 8.01-432 of the Code of Virginia of
1950, as amended, which judgment shall be confessed in the Clerk's Office of
the Circuit Court of Fairfax County, Virginia. The Borrower shall, upon the
Lender's request, name such additional or alternative persons designated by the
Lender as the Borrower's duly constituted attorney or attorneys-in-fact to
confess judgment against the Borrower in accordance with the terms hereof.
Furthermore, upon the Lender's request, the Borrower shall agree to the
designation of any additional circuit courts in the Commonwealth of Virginia in
which judgment may be confessed against the Borrower.

      Upon the occurrence of an Event of Default, the Borrower hereby
authorizes the above designated attorney-in-fact or any successor named
therefor to confess judgment against the Borrower for the amount of the unpaid
Principal Sum, all interest accrued and unpaid thereon, and all other amounts
payable by the Borrower to the Lender under the terms of this Note or any of
the other Financing Documents, together with court costs and attorneys' fees of
fifteen percent (15%) of the unpaid Principal Sum and interest then due
hereunder. The Borrower hereby releases, to the extent permitted by applicable
law, all errors and all rights of exemption, appeal, stay of execution,
inquisition, and other rights to which the Borrower may otherwise be entitled
under the laws of the United States of America or of any state or possession of
the United States of America now in force or which may hereafter be enacted.
The authority and power to appear for and enter judgment


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against the Borrower shall not be exhausted by one or more exercises thereof or
by any imperfect exercise thereof and shall not be extinguished by any judgment
entered pursuant thereto. Such authority may be exercised on one or more
occasions or from time to time as often as the Lender shall deem necessary or
desirable, for all of which this Note shall be a sufficient warrant.

      12.    Expenses.

      The Borrower promises to pay to the Lender on demand by the Lender all
reasonable costs and expenses incurred by the Lender in connection with the
collection and enforcement of this Note, including, without limitation, all
reasonable attorneys' fees and expenses and all court costs.

      13.    Notices.

      Any notice, request, or demand to or upon the Borrower or the Lender
shall be deemed to have been properly given or made when delivered in
accordance with Section 8.1 of the Financing Agreement.

      14.    Miscellaneous.

      Each right, power, and remedy of the Lender as provided for in this Note
or any of the other Financing Documents, or now or hereafter existing under any
applicable law or otherwise shall be cumulative and concurrent and shall be in
addition to every other right, power, or remedy provided for in this Note or
any of the other Financing Documents or now or hereafter existing under any
applicable law, and the exercise or beginning of the exercise by the Lender of
any one or more of such rights, powers, or remedies shall not preclude the
simultaneous or later exercise by the Lender of any or all such other rights,
powers, or remedies. No failure or delay by the Lender to insist upon the
strict performance of any term, condition, covenant, or agreement of this Note
or any of the other Financing Documents, or to exercise any right, power, or
remedy consequent upon a breach thereof, shall constitute a waiver of any such
term, condition, covenant, or agreement or of any such breach, or preclude the
Lender from exercising any such right, power, or remedy at a later time or
times. By accepting payment after the due date of any amount payable under the
terms of this Note, the Lender shall not be deemed to waive the right either to
require prompt payment when due of all other amounts payable under the terms of
this Note or to declare an Event of Default for the failure to effect such
prompt payment of any such other amount. No course of dealing or conduct shall
be effective to amend, modify, waive, release, or change any provisions of this
Note.

      15.    Partial Invalidity.

      In the event any provision of this Note (or any part of any provision) is
held by a court of competent jurisdiction to be invalid, illegal, or
unenforceable in any respect, such invalidity, illegality, or unenforceability
shall not affect any other provision (or remaining part of the affected
provision) of this Note; but this Note shall be construed as if such invalid,
illegal, or unenforceable provision (or part thereof) had not been contained in
this Note, but only to the extent it is invalid, illegal, or unenforceable.

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      16.    Captions.

      The captions herein set forth are for convenience only and shall not be
deemed to define, limit, or describe the scope or intent of this Note.

      17.    Governing Law.

      The provisions of this Note shall be construed, interpreted and enforced
in accordance with the laws of the Commonwealth of Virginia as the same may be
in effect from time to time.

      18.    Consent to Jurisdiction.

      The Borrower irrevocably submits to the jurisdiction of any state or
federal court sitting in the Commonwealth of Virginia over any suit, action, or
proceeding arising out of or relating to this Note. The Borrower irrevocably
waives, to the fullest extent permitted by law, any objection that the Borrower
may now or hereafter have to the laying of venue of any such suit, action, or
proceeding brought in any such court and any claim that any such suit, action,
or proceeding brought in any such court has been brought in an inconvenient
forum. Final judgment in any such suit, action, or proceeding brought in any
such court shall be conclusive and binding upon the Borrower and may be
enforced in any court in which the Borrower is subject to jurisdiction by a
suit upon such judgment provided that service of process is effected upon the
Borrower as provided in this Note or as otherwise permitted by applicable law.

      19.    Service of Process.

      The Borrower hereby irrevocably designates and appoints R.R. Bower, as
the Borrower's authorized agent to accept and acknowledge on the Borrower's
behalf service of any and all process that may be served in any suit, action,
or proceeding instituted in connection with this Note in any state or federal
court sitting in the Commonwealth of Virginia. If such agent shall cease so to
act, the Borrower shall irrevocably designate and appoint without delay another
such agent in the Commonwealth of Virginia satisfactory to the Lender and shall
promptly deliver to the Lender evidence in writing of such agent's acceptance
of such appointment and its agreement that such appointment shall be
irrevocable.

      The Borrower hereby consents to process being served in any suit, action,
or proceeding instituted in connection with this Note by (a) the mailing of a
copy thereof by certified mail, postage prepaid, return receipt requested, to
the Borrower and (b) serving a copy thereof upon the agent hereinabove
designated and appointed by the Borrower as the Borrower's agent for service of
process. The Borrower irrevocably agrees that such service shall be deemed to
be service of process upon the Borrower in any such suit, action, or
proceeding. Nothing in this Section shall affect the right of the Lender to
serve process in any manner otherwise permitted by law and nothing in this
Section will limit the right of the Lender otherwise to bring proceedings
against the Borrower in the courts of any jurisdiction or jurisdictions.

      20.    WAIVER OF TRIAL BY JURY.

      THE BORROWER HEREBY WAIVES TRIAL BY JURY IN ANY ACTION OR PROCEEDING TO
WHICH THE BORROWER AND THE LENDER MAY BE PARTIES, ARISING OUT OF OR IN ANY WAY
PERTAINING TO (A) THIS NOTE OR


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(B) THE FINANCING DOCUMENTS. IT IS AGREED AND UNDERSTOOD THAT THIS WAIVER
CONSTITUTES A WAIVER OF TRIAL BY JURY OF ALL CLAIMS AGAINST ALL PARTIES TO SUCH
ACTIONS OR PROCEEDINGS, INCLUDING CLAIMS AGAINST PARTIES WHO ARE NOT PARTIES TO
THIS NOTE.

      This waiver is knowingly, willingly and voluntarily made by the Borrower,
and the Borrower hereby represents that no representations of fact or opinion
have been made by any individual to induce this waiver of trial by jury or to
in any way modify or nullify its effect. The Borrower further represents that
it has been represented in the signing of this Note and in the making of this
waiver by independent legal counsel, selected of its own free will, and that it
has had the opportunity to discuss this waiver with counsel.

      21. Interest Rate Not to Exceed Applicable Laws.

      The interest rate required by this Note, the Financing Agreement or any
of the other Financing Documents shall not exceed the maximum rate permissible
under applicable laws, and any amounts paid in excess of such rate or rates
shall be applied to reduce the unpaid balance of the Principal Sum or shall be
refunded to the Borrower at the option of the Lender.

      22.    No Novation.

      This Note, is intended as a replacement of, and is in substitution for,
that certain Revolving Credit Note dated June 16, 1986 from the Borrower, as
maker, payable to the order of NationsBank, N. A. (as from time to time
extended, amended, restated, supplemented or otherwise modified, collectively,
the "Original Note"), but is not intended as a novation of the Original Note or
any of the Obligations evidenced by the Original Note. All references in the
Financing Agreement or any of the other Financing Documents to the Note shall
mean the Original Note, as amended and restated in accordance with the
provisions of this Note.

      IN WITNESS WHEREOF, the Borrower has caused this Note to be executed
under seal by its duly authorized officers as of the date first written above.

WITNESS OR ATTEST                   SENSYS TECHNOLOGIES INC.


/s/Darla Cavaliere                  By:  /s/R.R. Bower                  (SEAL)
--------------------------             ----------------------------------
                                         Name:    R.R. Bower
                                         Title:   V.P. Finance, CFO


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