Document:

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                                                                     Exhibit 4.1

       NUMBER                    PAR VALUE $.0001                    SHARES

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                           MARKLAND TECHNOLOGIES, INC.

               INCORPORATED UNDER THE LAWS OF THE STATE OF FLORIDA

COMMON STOCK                                         CUSIP 570658 10 4

                                             SEE REVERSE FOR CERTAIN DEFINITIONS

THIS CERTIFIES THAT

IS THE OWNER OF

         FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK of Markland
Technologies, Inc., transferable only on the books of the Corporation by the
holder hereof in person or by duly authorized attorney upon surrender of this
Certificate properly endorsed. This Certificate is not valid unless
countersigned and registered by the Transfer Agent and Registrar.
         WITNESS the facsimile seal of the Corporation and the facsimile
signatures of its duly authorized officers.

Dated                                     COUNTERSIGNED:
                                          Florida Atlantic Stock Transfer, Inc.
                                          7130 Nob Hill Road
                                          Tamarac, FL 33321 Transfer Agent

                  [MARKLAND TECHNOLOGIES, INC. CORPORATE SEAL]

         SECRETARY                                            PRESIDENT

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<S>      <C>                                            <C>

         The following abbreviations, when used in the inscription on the face
         of this certificate, shall be construed as though they were written out
         in full according to applicable laws or regulations:

  TEN COM -- as tenants in common                       UNIF GIFT MIN ACT -- ...........Custodian................
  TEN ENT -- as tenants by the entireties                                    (Cust)                 (Minor)
  JT TEN  -- as joint tenants with right of                                  under Uniform Gifts to Minors
                survivorship and not as tenants                              Act ................................
                in common                                                            (State)

     Additional abbreviations may also be used though not in the above list.

For value received, ______________ hereby sell, assign and transfer unto
PLEASE INSERT SOCIAL SECURITY OR OTHER
  IDENTIFYING NUMBER OF ASSIGNEE
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  PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE

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_Shares of the capital stock represented by the within Certificate, and do
hereby irrevocably constitute and appoint

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Attorney to transfer the said stock on the books of the within-named Corporation
with full power of substitution in the premises.

Dated, ___________________________

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       NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS
               WRITTEN UPON THE FACE OF THE CERTIFICATE, IN EVERY PARTICULAR,
               WITHOUT ALTERATION OR ENLARGEMENT OF ANY CHANGE WHATEVER.

</TABLE><PAGE>

                                                                    EXHIBIT 10.2

                           MARKLAND TECHNOLOGIES, INC.

         RESTATED AND AMENDED SECURED CONVERTIBLE REVOLVING CREDIT NOTE

$500,000                                                      New York, New York
                                                              As of June 4, 2002
                                                      Restated December 10, 2002

                            _________________________

THIS NOTE AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF (COLLECTIVELY THE
"SECURITIES") WERE ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER THE
SECURITIES ACT OF 1933, AS AMENDED ("SECURITIES ACT"), AND APPLICABLE STATE
SECURITIES LAWS. THE SECURITIES REPRESENTED HEREBY HAVE BEEN ACQUIRED FOR
INVESTMENT AND MAY NOT BE SOLD OR TRANSFERRED UNLESS SUCH SALE OR TRANSFER IS
COVERED BY AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND
APPLICABLE STATE SECURITIES LAW OR, IN THE OPINION OF COUNSEL TO THE ISSUER, IS
EXEMPT FROM THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND SUCH LAWS.
                            _________________________

                                Due June 30, 2004

         FOR VALUE RECEIVED, the undersigned, MARKLAND TECHNOLOGIES, INC., a
Florida corporation with its principal offices and place of business at 49
Quinnipiac Avenue, Unit H, North Haven, CT 06473 (the "Borrower"), promises to
pay to the order of MARKET LLC, a Cayman Islands, BVI limited liability company
with an address at c/o Citco Trustees (Cayman) Limited, P.O. Box 31106 SMB,
Grand Cayman, Cayman Islands, British West Indies (the "Lender"), or at such
other place as may be designated from time to time by the Lender, the unpaid
amount of all sums that have been advanced to or for the benefit of the Borrower
in accordance with the terms hereof, not to exceed the aggregate principal sum
of FIVE HUNDRED THOUSAND DOLLARS ($500,000), lawful money of the United States
of America, plus interest on the unpaid principal balance computed from the date
hereof, at the per annum rate set forth below. Unless otherwise stated herein,
capitalized terms shall have the meanings as set forth in that certain Loan and
Security Agreement dated August 5, 1999 as amended, among Lender and Borrower
and Vidikron of America, Inc. (Vidikron"), Borrower's subsidiary (the "Loan
Agreement").

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         1. INTEREST. This Note shall bear interest at the rate per annum equal
to six (6%) percent per annum calculated on the basis of a 360-day year and
actual number of days elapsed.

         Notwithstanding any provision to the contrary contained herein, it is
expressly understood and agreed between the Lender and the Borrower that the
Lender shall not collect a rate of interest on any obligation or liability due
and owing by the Borrower to the Lender in excess of the maximum contract rate
of interest permitted by law. It is the intent of the Lender and the Borrower
that the interest laws adopted by the State of New York shall govern the
relationship between the parties hereto, but in the event of a final
adjudication to the contrary, the Borrower, NUNC PRO TUNC, shall be obligated to
pay to the Lender only such interest as then shall be permitted by the law of
the jurisdiction found to govern the contract relationship between the Borrower
and the Lender. All interest found in excess of that rate of interest allowed
and collected by the Lender shall be applied to the balance of the principal due
hereunder in such manner as to prevent the payment and collection of interest in
excess of the rate permitted under applicable law.

         2. SECURITY INTEREST. This Note is secured by (a) a continuing
first-in-priority security interest in substantially all of the Borrower's
assets as provided for in that certain Amendment and Assignment and Assumption
Agreement dated September 21, 2001 by and between Borrower and Lender (the
"Amendment") , and (b) a continuing first-in-priority security interest in
substantially all of the Vidikron's assets as provided for in the Loan Agreement
and reaffirmed in the Amendment and that certain Debt Restructuring Agreement
dated June 4, 2002 between and among Borrower, Lender and Vidikron (the "Debt
Restructuring Agreement").

         3. NO NOVATION. The indebtedness of the Borrower incurred by reason of
revolving loans made pursuant to the Loan Agreement is evidenced by prior notes
issued pursuant to the Loan Agreement to Borrower or its
predecessor-in-interest, including, most recently, a $4,500,000 Amended Secured
Convertible Revolving Credit Note payable by Borrower. (the "Prior Note").
Nothing herein or in any other document shall be construed to extinguish or deem
the Prior Note satisfied, or to be a novation of the Prior Note or to release or
terminate any lien or security interest that secures payment of the Prior Note
to the extent of $500,000 [and accrued interest]. This Note shall be in partial
renewal, continuation and modification of, but not in revocation or discharge
of, the Prior Note, and the indebtedness thereunder shall be deemed expressly
incorporated herein.

         This Note evidences the outstanding principal as of December 9, 2002 of
the Revolving Credit Loan described in and is the Revolving Credit Note referred
to in the Loan Agreement and is governed by and entitled to the benefits
contained in the Loan Agreement and is secured by the security interests granted
therein and in the other Loan Documents referred to and described therein,
which, among other things, contain provisions for acceleration of the maturity
hereof upon the occurrence of certain events, and is being executed and
delivered pursuant to the Debt Restructuring Agreement.

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         4. CONVERSION.

                  (a) Subject to and upon compliance hereinbelow, the entire
outstanding principal amount of this Note, or any portion thereof, is
convertible into shares of common stock of the Borrower (the "Common Stock") at
the option of the Lender at any time. On conversion of the entire outstanding
principal amount of this Note, or any portion thereof, any interest that is past
due on the principal amount of this Note that is being converted shall be paid
in U.S. currency.

                  (b) The total number of shares of Common Stock issuable upon
conversion shall be determined by dividing the principal amount of this Note
being converted by eighty percent (80%) of the closing bid price of the Common
Stock based on the average of the five (5) trading days immediately preceding
the date of conversion.

                  (c) Nothing in this Note shall grant, or shall be deemed to
constitute the incurrence, creation, assumption or sufferance by the Borrower
of, and the Lender shall not assert, any mortgage, pledge, lien, charge or other
encumbrance of any nature whatsoever on the Common Stock deliverable upon
conversion of this Note.

                  (d) To exercise the conversion privilege, the Lender shall
surrender this Note, duly endorsed or assigned to the Borrower or in blank, at
the office designated in writing by the Borrower, accompanied by written notice
to the Borrower.

                  (e) This Note shall be deemed to have been converted
immediately prior to the close of business on the day of surrender of this Note
for conversion in accordance with the foregoing provisions, and at such time the
rights of the Lender shall cease, and the person or persons, or entity or
entities, entitled to receive the Common Stock issuable upon conversion shall be
treated for all purposes as the record holder or holders of such Common Stock at
such time. As promptly as practicable on or after the day of conversion, the
Borrower shall issue and shall deliver at its principal office or other office
or agency which it may designate in writing to the Lender a certificate or
certificates for the number of shares of Common Stock issuable upon conversion
(which may include fractional shares, as applicable).

                  (f) If this Note is converted in part only, upon such
conversion the Borrower shall execute and deliver to the Lender, at the expense
of the Borrower, a new Note or Notes of authorized denominations in aggregate
principal amount equal to the unconverted portion of the principal amount of
this Note.

         RESTRICTIVE COVENANT. Notwithstanding anything to the contrary in this
Note, in no event shall the Lender be entitled to exercise or convert any
portion of this Note in excess of that number of shares of Common Stock that,
upon giving effect to such exercise or conversion, would cause the aggregate
number of shares of Common Stock beneficially owned by the Lender and its
affiliates to exceed 4.99% of the outstanding shares of the Common Stock
following such exercise. For purposes of this covenant, beneficial ownership
shall be calculated in accordance with Section 13(d) of the Securities Exchange
Act of 1934, as amended, without giving effect to the unconverted portion of
this Note.

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         PREPAYMENT. There shall be no prepayment premium in the event the
Borrower prepays any principal or accrued interest thereon.

         EVIDENCE OF DEBT. The Borrower hereby requests, authorizes, and
empowers any officer or employee of the Lender who may be directed by the Lender
from time to time to make notations of advances, payments and resulting
outstanding balances on the Grid Schedule attached to this Note, and on
additional Grid Schedule sheets as may be used by the Lender from time to time,
and agrees to be bound by and to be liable to the Lender for repayment of the
outstanding principal balances as shown to be due and owing on such Grid
Schedule sheets from time to time, plus accrued interest thereon. The Grid
Schedule is incorporated herein and made a part of this Note. Notwithstanding
the foregoing, the Lender or the Borrower may establish, by extrinsic evidence,
that the outstanding balance of the Note is greater or less than the amount
shown on the Grid.

         DEFAULT. Upon the occurrence of one or more Events of Default as
provided in the Loan Agreement, the entire disbursed and unpaid principal, and
the interest thereon shall, subject to any applicable cure periods, become
immediately due and payable without presentment or protest or other notice or
demand, all of which are expressly waived by the Borrower.

         NO WAIVER. The powers and remedies given hereby shall not be exclusive
of any other powers and remedies available to the Lender. No course of dealings
between the Borrower and the Lender and no delay on the part of the Lender in
exercising any rights with respect to any default shall operate as a waiver of
any rights of the Lender. Failure on the part of the Lender to exercise any
rights with respect to any default shall not operate as a waiver of any rights
with respect to any other default.

         COSTS. The Borrower agrees to pay all costs and expenses incurred by
the Lender in enforcing this Revolving Credit Note, including, without
limitation, reasonable attorneys' fees and legal expenses.

         AMENDMENT. This Revolving Credit Note may not be waived, changed,
modified or discharged orally, but only by agreement in writing signed by the
party against whom any enforcement of any waiver, change modification or
discharge is sought.

         THIS SECURED CONVERTIBLE REVOLVING CREDIT NOTE SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK APPLICABLE TO
CONTRACTS MADE AND TO BE PERFORMED WHOLLY WITHIN THE STATE OF NEW YORK. BORROWER
HEREBY WAIVES THE RIGHT TO A JURY TRIAL AND CONSENTS TO JURISDICTION IN THE
FEDERAL OR STATE COURTS OF THE STATE OF NEW YORK WITH RESPECT TO THE ENFORCEMENT
OF THE TERMS HEREOF AND THE COLLECTION OF THE OBLIGATIONS HEREUNDER.

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         IN WITNESS WHEREOF, the Borrower has duly executed this Secured
Convertible Revolving Credit Note the day and year first above written.

                                       MARKLAND TECHNOLOGIES, INC.

                                       By: /s/ Ken Ducey
                                           -------------------------------------
                                           Ken Ducey
                                           Chief Financial Officer and Secretary

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                             GRID SCHEDULE
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                                                      UNPAID       PERSON
  DATE OF      AMOUNT OF    PRINCIPAL    INTEREST    PRINCIPAL     MAKING
TRANSACTION      LOAN       PAYMENTS     PAYMENTS     BALANCE     NOTATION
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6/10/02        500,000
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