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                                                                     EXHIBIT 4.3

                        GRANITE BROADCASTING CORPORATION

                                       TO

                              THE BANK OF NEW YORK,
                                   AS TRUSTEE

                                ----------------

                          FIRST SUPPLEMENTAL INDENTURE

                          DATED AS OF DECEMBER 19, 2003

                                       TO

                                    INDENTURE

                            DATED AS OF MAY 11, 1998

                                ----------------

                       8 - 7/8% SENIOR SUBORDINATED NOTES

                                DUE MAY 15, 2008

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         FIRST SUPPLEMENTAL INDENTURE, dated as of December 19, 2003 (this
"First Supplemental Indenture"), between Granite Broadcasting Corporation, a
Delaware corporation (the "Company"), and The Bank of New York, a New York
banking corporation, as trustee (the "Trustee").

         WHEREAS, the Company and the Trustee executed an Indenture, dated as of
May 11, 1998 between the Company and the Trustee (the "Indenture"), in respect
of the Company's 8-7/8% Senior Subordinated Notes due May 15, 2008 (the
"Notes");

         WHEREAS, Section 902 of the Indenture provides that modifications and
amendments to the Indenture may be made and indentures supplemental to the
Indenture may be entered into by the Company and the Trustee with the consent of
the holders (the "Holders") of not less than a majority in principal amount of
the Notes outstanding, except for certain specific events which require the
unanimous consent of the Holders of the Notes;

         WHEREAS, the Company undertook an offer to purchase and consent
solicitation pursuant to a statement dated December 9, 2003, offering to
purchase the Holders' Notes for cash and requesting that the Holders give their
consent to implement the amendments to the Indenture set forth in this First
Supplemental Indenture (the "Amendments");

         WHEREAS, the Company has received the consents of the Holders of not
less than a majority in principal amount outstanding of the Notes consenting to
the substance of the Amendments set forth in this First Supplemental Indenture;

         WHEREAS, all conditions and requirements necessary to make this First
Supplemental Indenture a valid, binding, and legal instrument in accordance with
the terms of the Indenture have been performed and fulfilled and the execution
and delivery hereof have been in all respects duly authorized; and

         WHEREAS, in accordance with the terms of the Indenture, the Company has
requested that the Trustee execute and deliver this First Supplemental
Indenture.

         NOW, THEREFORE, in consideration of the above premises, each party
agrees, for the benefit of the other and for the equal and ratable benefit of
the Holders of Notes, as follows:

                                    ARTICLE I

                                   AMENDMENTS

         Section 101. Indenture Amendments. The Indenture is hereby amended as
follows:

         (a) The table of contents of the Indenture is hereby amended by (i)
         replacing the heading "Mergers, Consolidations and Certain Sales of
         Assets" appearing next to Section 801 with the heading "[intentionally
         omitted]"; (ii) replacing the heading "Successor Substituted" appearing
         next to Section 802 with the heading "[intentionally omitted]"; (iii)
         replacing the heading "Limitation on Company Debt" appearing next to
         Section 1008 with the heading "[intentionally omitted]"; (iv) replacing
         the heading "Limitation on Certain Debt" appearing next to Section 1009
         with the heading "[intentionally omitted]";

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         (v) replacing the heading "Limitation on Restricted Payments" appearing
         next to Section 1010 with the heading "[intentionally omitted]"; (vi)
         replacing the heading "Limitations Concerning Distributions by and
         Transfers to Subsidiaries" appearing next to Section 1011 with the
         heading "[intentionally omitted]"; (vii) replacing the heading
         "Limitation on Transactions with Affiliates" appearing next to Section
         1012 with the heading "[intentionally omitted]"; (viii) replacing the
         heading "Limitation on Certain Asset Dispositions" appearing next to
         Section 1013 with the heading "[intentionally omitted]"; (ix) replacing
         the heading "Limitation on Issuances and Sales of Capital Stock of
         Wholly Owned Subsidiaries" appearing next to Section 1014 with the
         heading "[intentionally omitted]"; (x) replacing the heading
         "Limitation on Liens Securing Company Subordinated Debt" appearing next
         to Section 1015 with the heading "[intentionally omitted]"; (xi)
         replacing the heading "Limitation on Guarantees of Company Subordinated
         Debt" appearing next to Section 1016 with the heading "[intentionally
         omitted]"; (xii) replacing the heading "Change of Control" appearing
         next to Section 1017 with the heading "[intentionally omitted]"; and
         (xiii) replacing the heading "Provision of Financial Information"
         appearing next to Section 1018 with the heading "[intentionally
         omitted]".

         (b) The definitions of "Asset Disposition", "Attributable Value",
         "Average Life", "Capital Lease Obligation", "Change of Control",
         "Consolidated Cash Flow", "Consolidated Income Tax Expense",
         Consolidated Interest Expense", "Consolidated Net Income",
         "Disqualified Stock", "Incur", "Investment", "Lien", "Local Marketing
         Agreement", "Net Available Proceeds", "Permitted Holder", "Permitted
         Television Investment", "Preferred Stock", "Pro Forma Consolidated Cash
         Flow" and "Sale and Leaseback Transaction", which are set forth in
         Section 101 of the Indenture are deleted in their entirety.

         (c) Sections 501(3), 501(4), 501(5) and 501(10) are each amended by
         deleting the text in its entirety and inserting in lieu thereof
         "[intentionally omitted]".

         (d) Article Eight is amended by deleting the text of Sections 801 and
         802 in their entirety and inserting in lieu thereof "[intentionally
         omitted]".

         (e) Sections 1008, 1009, 1010, 1011, 1012, 1013, 1014, 1015, 1016, 1017
         and 1018 are each amended by deleting the text in its entirety and
         inserting in lieu thereof "[intentionally omitted]".

         Section 102. Mutatis Mutandi Effect. The Indenture, as supplemented, is
hereby amended mutatis mutandi to reflect the amendment of each of the defined
terms incorporated in the Indenture pursuant to Section 101 above.

                                   ARTICLE II

                             MISCELLANEOUS PROVISONS

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         Section 201. Terms Defined. For all purposes of this First Supplemental
Indenture, except as otherwise defined herein, capitalized terms used in this
First Supplemental Indenture shall have the meanings ascribed to such terms in
the Indenture.

         Section 202. Indenture. Except as amended hereby, the Indenture and the
Notes are in all respects ratified and confirmed and all their terms shall
remain in full force and effect. From and after the effectiveness of this First
Supplemental Indenture, any reference to the Indenture shall mean the Indenture
as so amended by this First Supplemental Indenture.

         Section 203. Governing Law. The internal laws of the State of New York
shall govern this First Supplemental Indenture, without regard to the principles
of conflicts of law thereof.

         Section 204. Successors. All agreements of the Company and the Trustee
in this First Supplemental Indenture, the Indenture and the Notes shall bind
their respective successors and assigns. This First Supplemental Indenture shall
be binding upon each Holder of Notes and their respective successors and
assigns.

         Section 205. Multiple Counterparts. The parties may sign multiple
counterparts of this First Supplemental Indenture. Each signed counterpart shall
be deemed an original, but all of them together shall represent the same
agreement.

         Section 206. Effective Date of this First Supplemental Indenture. This
First Supplemental Indenture and the Amendments to Sections 101, 501(3), 501(4),
501(5), 501(10), 801, 802, 1008, 1009, 1010, 1011, 1012, 1013, 1014, 1015, 1016,
1017 and 1018 shall be effective pursuant to Section 904 of the Indenture
immediately upon execution by the Company and delivery to and execution by the
Trustee of this First Supplemental Indenture.

         Section 207. Trustee Disclaimer. The Trustee accepts the amendment of
the Indenture effected by this First Supplemental Indenture and agrees to
execute the trust created by the Indenture as hereby amended, but only upon the
terms and conditions set forth in the Indenture, including the terms and
provisions defining and limiting the liabilities and responsibilities of the
Trustee, which terms and provisions shall in like manner define and limit its
liabilities and responsibilities in the performance of the trust created by the
Indenture as hereby amended. Without limiting the generality of the foregoing,
the Trustee shall not be responsible in any manner whatsoever for or with
respect to any of the recitals or statements contained herein, all of which
recitals or statements are made solely by the Company, or for or with respect to
(i) the validity, efficacy, or sufficiency of this First Supplemental Indenture
or any of the terms or provisions hereof, (ii) the proper authorization hereof
by the Company by corporate action or otherwise, or (iii) the due execution
hereof by the Company and the Trustee makes no representation with respect to
any such matters.

         Section 208. Separability Clause. In case of any clause of this First
Supplemental Indenture shall be invalid, illegal, or unenforceable, the
validity, legality, and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

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                                   SIGNATURES

         IN WITNESS WHEREOF, the parties hereto have caused this First
Supplemental Indenture to be duly executed, all as of the date first above
written.

                                         GRANITE BROADCASTING CORPORATION
                                           as Issuer

                                         By: /s/ Lawrence I. Wills
                                             -------------------------------
                                            Name:   Lawrence I. Wills
                                            Title:  Senior Vice President

                                         THE BANK OF NEW YORK
                                           as Trustee

                                         By: /s/ Julie Salovitch - Miller
                                             -------------------------------
                                            Name:   Julie Salovitch - Miller
                                            Title:  Vice President