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                                                                   Exhibit 10.77

                              THIRD PROMISSORY NOTE

US $6,150,000                                                  December 29, 1999

     IAT Multimedia, Inc. (the "Purchaser") hereby promises to pay to Carlo
Petrini (the "Noteholder"), or registered assignees, by wire transfer of
immediately available funds to the account designated below, in lawful currency
of the United States of America, the principal amount of SIX MILLION ONE HUNDRED
FIFTY THOUSAND US DOLLARS ($6,150,000) at the Maturity Date. This Third
Promissory Note shall be a non-interest bearing note. All the terms not
otherwise defined herein shall have the meaning ascribed to them in that certain
Stock Purchase Agreement (the "Agreement"), dated as of November 3, 1999, by and
between Gruppo Spigadoro N.V. and the Purchaser. This Third Promissory Note is
the promissory note referred to in Schedule 2.2, item #3 of the Agreement.

     1. Maturity Date. As used herein, the term "Maturity Date" shall mean
December 31, 2000.

     2. Payment Instructions. All payments due under this note shall be by wire
transfer to:

        Finnat Euramerica S.p.A.
        Piazza del Gesu no. 49
        00186 Roma
        ABI 03087
        CAB 03200
        C/c no. 45605
        For Carlo Petrini

     3. Prepayment. The Purchaser may, at any time, but shall not be required
to, prepay, in whole or in part, amounts due under this Third Promissory Note.

     4. Security. This Third Promissory Note is secured by a guaranty of Seller
and a pledge of Purchaser Common Stock pursuant to a Stock Pledge Agreement (the
"Stock Pledge Agreement"), dated as of the date hereof, by and between the
Seller and the Noteholder.

     5. Conversion of Promissory Note. (a) This Third Promissory Note shall be
convertible into shares of Purchaser Common Stock at the option of the
Noteholder, in whole or in part, at any time and from time to time, at a
conversion price equal to the greater of $2.50 or 85% of the average closing
price of Purchaser Common Stock as reported by the primary stock market or
exchange on which the Purchaser Common Stock is traded for the five (5) trading
days prior to the notice of conversion (the "Conversion Notice"). Each
Conversion Notice shall be in writing and shall specify the principal amount of
the note to be converted and the date on which such conversion is to be
effected, which date may not be prior to the date such Conversion Notice is
deemed to have been delivered hereunder (the "Conversion Date"). If no
Conversion
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Date is specified in the Conversion Notice, the Conversion Date shall be the
date that such Conversion Notice is deemed delivered hereunder. Any Conversion
Notice given shall be irrevocable. If the Noteholder is requiring conversion of
less than all of the principal amount represented by this Third Promissory Note,
the Purchaser shall promptly deliver to the Noteholder a new note for such
principal amount as has not been converted.

     (b) The number of shares so delivered under (a) above shall be further
adjusted by the Board of Directors of the Purchaser or, an authorized committee
thereof, to reflect any issuance of new stock, stock dividend, common stock
split, share combination, exchange of shares, merger, consolidation,
recapitalization, separation, reorganization, liquidation or extraordinary
dividend or similar transaction payable in stock of the Purchaser all for the
purpose of providing dilution protection for the Seller.

     6. Successors and Assignees. The terms of this Third Promissory Note shall
be binding upon and inure to the benefit of and be enforceable by the respective
successors and permitted assignees of the Purchaser and the Noteholder, and,
enforceable by any holder or holders of this Third Promissory Note; provided
that the rights, obligations, covenants and agreements of the Purchaser under
this Third Promissory Note may not be assigned or delegated, as applicable,
without the written consent of the Noteholder. In the event of any such transfer
and assignment of this Third Promissory Note, the Purchaser shall, upon
surrender of this Third Promissory Note to the Purchaser, execute and deliver in
exchange therefor a new note. Each such new note shall be registered in the name
of such person as the Noteholder or other holder of the surrendered Third
Promissory Note may request.

     7. Notices. All notices and other communications with respect to this Third
Promissory Note shall be in writing and shall be sent by hand delivery, receipt
acknowledged, or by facsimile transmission, as follows:

If to the Noteholder, to:

     Sig. Carlo Petrini
     Petrini S.p.A.
     Bastia Umbra (Perugia)
     Italy
     Telefax:  39-758009341

If to the Purchaser, to:

     Jacob Agam, Chairman
     IAT Multimedia, Inc.
     70 East 55th Street
     New York, New York 10022
     Telefax:  212-754-4044

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with copies to:

     Steven Skolnick, Esq.
     Lowenstein Sandler PC
     65 Livingston Avenue
     Roseland, New Jersey 07068
     Telefax:  973-597-2400

     8. Modifications and Amendments. No modification, rescission, waiver,
forbearance, release or amendment of any provision of this Third Promissory Note
shall be made, except by a written agreement duly executed by the Purchaser and
the Noteholder.

     9. Jurisdiction; Governing Law. The Purchaser and Noteholder (a)
acknowledge and agree that, in any suit, action or proceeding under this
promissory note, the courts of the State of New York or the courts of the United
States District Court for the Southern District of New York shall have the
exclusive jurisdiction thereof and (b) consent to and waive any objection which
the Noteholder now has or may hereafter have to proper venue existing in any of
such courts. This promissory note shall be governed by, and construed in
accordance with, the laws of the State of New York, without regard to conflict
of laws principles thereof.

     10. Lost, Mutilated or Stolen Note. Upon receipt of evidence, reasonably
satisfactory to the Purchaser of the loss, theft, destruction or mutilation of
this Third Promissory Note and, in the case of any such mutilation, upon the
surrender of this Third Promissory Note for cancellation to the Purchaser at its
principal office, the Purchaser will execute and deliver, in lieu thereof, a new
note of like tenor containing the same terms as this Third Promissory Note,
dated so that there will be no loss of interest on such lost, stolen, destroyed
or mutilated Third Promissory Note. Any Third Promissory Note in lieu of which
any such new note has been so executed and delivered by the Purchaser shall not
be deemed to be an outstanding Third Promissory Note for any purposes.

     11. Headings. Paragraph headings used in this Third Promissory Note are for
convenience of reference only, are not part of this Third Promissory Note and
are not to effect the construction of, or to be taken into consideration in
interpreting, this Third Promissory Note.

     12. Severability. If any provision of this Third Promissory Note is held by
a court of competent jurisdiction to be invalid, void or unenforceable, the
remainder of the provisions of this Third Promissory Note shall remain in full
and effect.

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         IN WITNESS WHEREOF, the undersigned hereto has caused this Third
Promissory Note to be executed by its duly authorized officers as of the date
Third above written.

                                             IAT MULTIMEDIA, INC.

                                             By: /s/ Jacob Agam
                                                -----------------------------
                                                Name: Jacob Agam
                                                Title: Chairman of the Board and
                                                       Chief Executive Officer

AGREED AND ACCEPTED:

/s/ Carlo Petrini
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CARLO PETRINI



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