Exhibit 10.1
Form 8-K
Viking Systems, Inc.
File No. 000-49636

Neither this  Convertible  Promissory  Note nor the shares of common stock which
will be issued if this Note is converted  into shares of common stock,  has been
registered  under the Securities Act of 1933 or applicable state securities laws
and may not be  sold,  transferred,  assigned,  offered,  pledged  or  otherwise
distributed  for value  without  the  express  written  consent of the Maker and
Maker's receipt of an opinion of counsel acceptable to the Maker that such sale,
transfer,  assignment,  offer,  pledge or other distribution for value is exempt
from the registration and prospectus delivery  requirements of such Act and such
laws.

$500,000 January 21, 2005

                          CONVERTIBLE PROMISSORY NOTE


     FOR VALUE RECEIVED,  Viking Systems,  Inc., a Nevada corporation ("Maker"),
hereby promises to pay to the order of Donald E. Tucker ("Payee"), the principal
sum of FIVE HUNDRED THOUSAND Dollars (U.S. $500,000.00),  together with interest
thereon  from the date  hereof  accruing  at the rate of ten  percent  (10%) per
annum.  Principal and all accrued interest shall be payable in full on or before
March 31, 2005.  This Note is unsecured.  This Note  supercedes and replaces the
Convertible Promissory Note in the amount of $450,000 of January 12, 2004.

                                  PAYMENT TERMS

     Principal and Interest.  The principal  amount of this Note,  together with
all accrued interest, shall be due and payable on or before March 31, 2005.

     Manner of Payment.  All  payments of  principal  and  interest on this Note
shall be made payable to Payee and mailed to 1626 Clemson  Circle,  La Jolla, CA
93027 or at such  other  place in the United  States of  America as Payee  shall
designate  to Maker in writing.  If any payment of principal or interest on this
Note is due on a day which is not a Business  Day,  such payment shall be due on
the next succeeding Business Day, and such extension of time shall be taken into
account in calculating the amount of interest payable under this Note. "Business
Day" means any day other than a Saturday,  Sunday or legal  holiday in the State
of Nevada.

     Prepayment.  Maker may,  without  premium or penalty,  at any time and from
time to time, prepay all or any portion of the outstanding principal balance due
under this Note,  provided that each such  prepayment is  accompanied by accrued
interest  on the  amount of  principal  prepaid  calculated  to the date of such
prepayment.






                                     DEFAULT

     The  occurrence of any one or more of the following  events with respect to
Maker shall constitute an event of default hereunder ("Event of Default"):

     (a)  If Maker  shall  fail to pay  when due any  payment  of  principal  or
          interest on this Note and such failure continues for fifteen (15) days
          after Payee notifies Maker therein writing;

     (b)  The Maker shall default in the  observance or performance of any other
          term, covenant or agreement contained herein and the same shall not be
          cured within fifteen (15) days of the occurrence thereof;

     (c)  If, pursuant to or within the meaning of the United States  Bankruptcy
          Code or any other  federal  or state law  relating  to  insolvency  or
          relief of  debtors (a  "Bankruptcy  Law"),Maker  shall (i)  commence a
          voluntary  case or  proceeding;  (ii) consent to the entry of an order
          for relief  against it in an  involuntary  case;  (iii) consent to the
          appointment of a trustee,  receiver,  assignee,  liquidator or similar
          official; (iv) make an assignment for the benefit of its creditors; or
          (v) admit in writing  its  inability  to pay its debts as they  become
          due.

     (d)  If a court of competent  jurisdiction  enters an order or decree under
          any  Bankruptcy  Law  that  (i)  is for  relief  against  Maker  in an
          involuntary  case,  (ii)  appoints  a  trustee,  receiver,   assignee,
          liquidator  or  similar  official  for Maker or  substantially  all of
          Maker's assets,  or (iii) orders the liquidation of Maker, and in each
          case the order or decree is not dismissed within 120 days.

                                    REMEDIES

     Upon the occurrence of an Event of Default  hereunder (unless all Events of
Default  have been cured or waived by Payee),  Payee may, at its option,  (i) by
written  notice to Maker,  declare the entire unpaid  principal  balance of this
Note,  together with all accrued interest  thereon,  immediately due and payable
regardless  of any prior  forbearance  and (ii)  exercise any and all rights and
remedies available to it under applicable law,  including,  without  limitation,
the right to collect  from Maker all sums due under this Note.  Maker  shall pay
all  reasonable  costs  and  expenses  incurred  by or on  behalf  of  Payee  in
connection with Payee's  exercise of any or all of its rights and remedies under
this Note, including, without limitation, reasonable attorneys' fees.

                          CONVERSION INTO COMMON STOCK

     The unpaid  principal  amount of the Note and accrued interest thereon may,
at the  election  of Payee,  be  converted  in full or part into  fully paid and
nonassessable shares of common stock of Maker at a rate of $.50 per share.

     Manner Of  Conversion.  This Note may be converted by Maker by surrender of
this Note, to Maker at its principal  office at 7514 Girard Avenue,  Suite 1509,

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La Jolla,  CA 92037 (or at such other  office as the Maker  shall  designate  to
Payee from time to time).  The conversion  shall be deemed to have been effected
immediately  prior to the close of  business on the date on which the Note shall
have been so surrendered to the Maker.

     Delivery  of Stock  Certificates.  As  promptly  as  practicable  after the
conversion  of this Note,  and in any event within thirty days  thereafter,  the
Maker at its expense  will  issue,  authenticate  and deliver to the  converting
Lender the certificate or certificates  for the number of shares of common stock
issuable upon such conversion.  All shares of the common stock which shall be so
deliverable  shall be duly and validly issued and fully paid and  nonassessable.
Each certificate shall bear the following legend: THE SECURITIES  REPRESENTED BY
THIS  CERTIFICATE  HAVE NOT BEEN REGISTERED  UNDER THE SECURITIES ACT OF 1933 OR
APPLICABLE STATE SECURITIES LAWS, AND ACCORDINGLY, MAY NOT BE SOLD, TRANSFERRED,
PLEDGED,  HYPOTHECATED  OR OTHERWISE  DISPOSED OF IN THE ABSENCE OF REGISTRATION
UNDER SUCH ACT AND SUCH LAWS OR PURSUANT TO AN EXEMPTION THEREFROM.

     Covenant to Reserve Shares for Conversion.  Maker covenants that it will at
all times reserve and keep available, out of its authorized common stock, solely
for the purpose of delivery upon  conversion of this Note, such number of shares
of common stock as shall then be deliverable upon the conversion of this Note.

      No Dilution. If the Maker:

          (i)  (A) makes a distribution in respect of the common stock in shares
               of common stock, (B) subdivides the outstanding  shares of common
               stock or (C) combines the outstanding shares of common stock into
               a  smaller   number  of   shares,   in  each  case   whether   by
               reclassification or recapitalization  (including reclassification
               or recapitalization by way of merger or consolidation); or

          (ii) issues to  holders  of shares of common  stock as a  dividend  or
               distribution,   (including   by   way  of   reclassification   or
               recapitalization),  any right or  warrant to  purchase  shares of
               common stock,  or any other security  convertible  into shares of
               common stock; or

          (iii)issues,  sells or  exchanges  shares of  common  stock for a cash
               price less than the fair market value of such common stock on the
               date of such  issuance,  sale or exchange  other than pursuant to
               options or  commitments  to issue  securities  outstanding on the
               date of the Note; or

          (iv) makes a  distribution  in respect  of the common  stock by way of
               dividend,   distribution   reclassification  or  recapitalization

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               (including  by way of merger or  consolidation),  or  redeems  or
               repurchases any common stock;

then the Maker shall promptly  adjust the number of shares of common stock to be
received upon  conversion  hereunder so that the fair market value of the shares
to be received by Payee  following  any of the events  described in (i)-(iv) and
the  adjustment  is equal to the fair market value of the shares that would have
been received by Purchaser if conversion  had taken place  immediately  prior to
such event and adjustment.

     Disclosures. Payee understands and acknowledges that the there is no active
market for the Maker's  common  stock,  and Maker will likely  operate at a loss
during the year ended December 31, 2004. Payee understands that an investment in
Maker is a high risk  investment.  Payee  understands  that the $.50  conversion
price has been  arbitrarily  determined and does not indicate that the shares of
Maker's common  stock's are worth,  or have a value of, $.50 per share under any
criteria of valuation.

     Availability  of  Information.  The Maker  undertakes to make  available to
Payee in connection with Payee's  decision as to whether Payee will convert this
Note, any reasonable and relevant information requested,  and undertakes to give
the Payee an  opportunity to ask questions of, and receive  answers from,  Maker
concerning any financial or other matter relating to the Maker.

                                     WAIVER

     The rights and  remedies of Payee under this Note shall be  cumulative  and
not alternative. No waiver by Payee of any right or remedy under this Note shall
be  effective  unless in writing  signed by Payee.  Neither  the failure nor any
delay in exercising any right,  power or privilege  under this Note will operate
as a waiver of such right,  power or privilege and no single or partial exercise
of any such  right,  power or  privilege  by Payee  will  preclude  any other or
further exercise of such right,  power or privilege or the exercise of any other
right,  power or privilege.  To the maximum extent  permitted by applicable law,
(a) no claim or right of Payee  arising  out of this Note can be  discharged  by
Payee,  in whole or in part, by a waiver or  renunciation  of the claim or right
unless in a writing,  signed by Payee;  (b) no waiver that may be given by Payee
will be applicable  except in the specific  instance for which it is given;  and
(c) no  notice  to or  demand  on Maker  will be  deemed  to be a waiver  of any
obligation  of Maker or of the  right of Payee to take  further  action  without
notice or demand as  provided in this Note.  Maker  hereby  waives  presentment,
demand, protest and notice of dishonor and protest.

                                OTHER PROVISIONS

     This Note shall be  construed  according  to, and shall be governed by, the
laws of the  State of  Nevada.  The  provisions  of this  Note  shall be  deemed
severable, so that if any provision hereof is declared invalid under the laws of
any state where it is in effect,  or of the United States,  all other provisions
of this Note shall  continue in full force and effect.  This Note may be amended
only by a writing signed on behalf of each party.

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     Any suit filed to enforce  this Note or  collect  the money owed  hereunder
shall be filed in any state or federal court having subject matter  jurisdiction
and  located  in San Diego  County,  California.  In any  action  or  proceeding
instituted  with  respect to any such claim,  Maker  irrevocably  submits to the
jurisdiction of such courts.

     This Note shall be binding upon the  successors  and assigns of Maker,  and
shall  inure  to the  benefit  of  and be  enforceable  by the  heirs,  personal
representatives, successors and assigns of Payee or any other holder hereof.

     IN WITNESS WHEREOF, the undersigned has duly executed, sealed and delivered
this Promissory Note the day and year first above written.

                              VIKING SYSTEMS, INC.,
                              a Nevada corporation




                              By:   /s/ Thomas B. Marsh
                                    CEO


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