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                                                                     EXHIBIT 4.2
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                           COX RADIO, INC., as Issuer,


                               CXR HOLDINGS, INC.,

                            as Subsequent Guarantor,


                                       and


                        THE BANK OF NEW YORK, as Trustee




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


                          FIRST SUPPLEMENTAL INDENTURE
                          Dated as of February 1, 1999


                                       TO


                                   INDENTURE,
                            Dated as of May 26, 1998

                                 Debt Securities


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







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                          FIRST SUPPLEMENTAL INDENTURE


         THIS FIRST SUPPLEMENTAL INDENTURE, dated as of February 1, 1999, by and
among COX RADIO, INC., a corporation duly organized and existing under the laws
of the State of Delaware (hereinafter called the "Company"), CXR HOLDINGS, INC.,
a corporation duly organized and existing under the laws of the State of Nevada
(the "Subsequent Guarantor"), and THE BANK OF NEW YORK, a New York banking
corporation, as trustee (hereinafter called the "Trustee"). Capitalized terms
used but not defined herein shall have the meanings ascribed to them in the
Indenture (as defined below).

                                   WITNESSETH:

         WHEREAS, the Company and the Trustee are parties to that certain
Indenture, dated as of May 26, 1998 (the "Indenture"), relating to $100,000,000
principal amount of the Company's 6.250% Notes due 2003 and $100,000,000
principal amount of the Company's 6.375% Notes due 2005; and

         WHEREAS, the Subsequent Guarantor was incorporated as a Nevada
corporation on September 11, 1998 and, as of the date hereof, the Subsequent
Guarantor is a wholly-owned Restricted Subsidiary of the Company; and

         WHEREAS, in connection with the Company's Credit Agreement, the
Subsequent Guarantor entered into a guarantee of the indebtedness under the
Company's Credit Agreement on February 1, 1999; and

         WHEREAS, in accordance with Section 10.12 of the Indenture, the Company
is required to cause the Subsequent Guarantor, for so long as the Subsequent
Guarantor is obligated to guarantee the Company's indebtedness pursuant to the
Credit Agreement, to fully and unconditionally guarantee the Securities by
executing and delivering to the Trustee this First Supplemental Indenture; and

         WHEREAS, Section 9.1(12) of the Indenture provides that the Trustee may
amend or supplement the Indenture or the Securities without the consent of the
Holders that does not adversely affect the interests of the Holders of any
Outstanding Securities; and

         WHEREAS, the Company, the Subsequent Guarantor and the Trustee desire
to enter into, execute and deliver this First Supplemental Indenture in
compliance with the foregoing provisions of the Indenture; and

         WHEREAS, all things prescribed by law and by the terms of the Indenture
necessary to make this First Supplemental Indenture, when duly executed and
delivered by the Company, the Subsequent Guarantor and the Trustee a valid and
binding instrument, enforceable in accordance with its terms, and otherwise to
effectuate the amendment of the Indenture, have been done and performed, and the
execution and delivery of this First Supplemental Indenture have been in all
respects duly authorized;

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         NOW, THEREFORE, in consideration of the above premises, the Company,
the Subsequent Guarantor and the Trustee covenant and agree as follows:


                                   ARTICLE ONE

                             Supplemental Indenture

         Section 1.01. This First Supplemental Indenture is a supplement to the
Indenture and does and shall be deemed to form a part of, and shall be construed
in connection with and as a part of, the Indenture for any and all purposes,
including but not limited to satisfaction and discharge of the Indenture as
provided in Article 4 of the Indenture.

         Section 1.02. This First Supplemental Indenture shall become effective
immediately upon execution and delivery by each of the Company, the Subsequent
Guarantor and the Trustee.

                                   ARTICLE TWO

                              Subsequent Guarantee

         Section 2.01. Subject to section 16.1 of the Indenture, for so long as
the Subsequent Guarantor is obligated to guarantee the Company's indebtedness
pursuant to the Credit Agreement, the Subsequent Guarantor hereby fully and
unconditionally guarantees the due and punctual payment of the principal of,
interest on and any other amounts payable under the Securities, when and if the
same shall become due and payable, whether at the Stated Maturity, by
declaration of acceleration, upon redemption, repurchase or repayment or
otherwise. The Subsequent Guarantor hereby further agrees to be bound by all
other provisions of the Indenture that are applicable to a "Subsequent
Guarantor" and the guarantee of the Subsequent Guarantor set forth in this First
Supplemental Indenture shall be subject to release upon the terms set forth in
the Indenture.

         Section 2.02. The Company hereby expressly ratifies, adopts, renews,
confirms and continues in full force and effect, without limitation, except as
hereby amended, each and every covenant, agreement, condition and provision
contained in the Indenture.

         Section 2.03. The Company and the Subsequent Guarantor covenant that
the recitals of fact and statements contained in this First Supplemental
Indenture are true and that, upon the execution and delivery of this First
Supplemental Indenture, the Company is not in default in any respect under any
of the provisions of the Indenture or of the Securities.


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                                  ARTICLE THREE

                              Additional Provisions

         Section 3.01. Except to the extent supplemented by Article Two of this
First Supplemental Indenture, the Indenture remains in full force and effect in
accordance with its terms. It shall not be necessary in connection with any
future reference to the Indenture to also make reference to this First
Supplemental Indenture.

         Section 3.02. The cover page of this First Supplemental Indenture and
all article and description headings are inserted for convenience of reference
only and are not to be taken to be any part of this First Supplemental Indenture
or to control or affect the meaning, construction or effect of the same.

         Section 3.03. The laws of the State of New York shall govern this First
Supplemental Indenture without regard to principles of conflicts of law.

         Section 3.04. This First Supplemental Indenture shall be simultaneously
executed in several counterparts, and all such counterparts executed and
delivered each as an original shall constitute but one and the same instrument.


                            [SIGNATURE PAGE FOLLOWS]



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


                                                  COX RADIO, INC.


                                                  By:  /s/ Robert F. Neil
                                                     --------------------------
                                                  Name: Robert F. Neil
                                                  Title: President


                                                  CXR HOLDINGS, INC.


                                                  By:  /s/ Robert F. Neil
                                                     --------------------------
                                                  Name: Robert F. Neil
                                                  Title: President


                                                  THE BANK OF NEW YORK,
                                                  as Trustee


                                                  By: /s/ Marie Trimboli
                                                     --------------------------
                                                  Authorized Signatory



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